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Sample records for counters phagosomal nox2

  1. SLAM is a microbial sensor that regulates bacterial phagosome functions in macrophages.

    Science.gov (United States)

    Berger, Scott B; Romero, Xavier; Ma, Chunyan; Wang, Guoxing; Faubion, William A; Liao, Gongxian; Compeer, Ewoud; Keszei, Marton; Rameh, Lucia; Wang, Ninghai; Boes, Marianne; Regueiro, Jose R; Reinecker, Hans-Christian; Terhorst, Cox

    2010-10-01

    Phagocytosis is a pivotal process by which macrophages eliminate microorganisms after recognition by pathogen sensors. Here we unexpectedly found that the self ligand and cell surface receptor SLAM functioned not only as a costimulatory molecule but also as a microbial sensor that controlled the killing of gram-negative bacteria by macrophages. SLAM regulated activity of the NADPH oxidase NOX2 complex and phagolysosomal maturation after entering the phagosome, following interaction with the bacterial outer membrane proteins OmpC and OmpF. SLAM recruited a complex containing the intracellular class III phosphatidylinositol kinase Vps34, its regulatory protein kinase Vps15 and the autophagy-associated molecule beclin-1 to the phagosome, which was responsible for inducing the accumulation of phosphatidylinositol-3-phosphate, a regulator of both NOX2 function and phagosomal or endosomal fusion. Thus, SLAM connects the gram-negative bacterial phagosome to ubiquitous cellular machinery responsible for the control of bacterial killing.

  2. NOX2-dependent regulation of inflammation.

    Science.gov (United States)

    Singel, Kelly L; Segal, Brahm H

    2016-04-01

    NADPH oxidase (NOX) isoforms together have multiple functions that are important for normal physiology and have been implicated in the pathogenesis of a broad range of diseases, including atherosclerosis, cancer and neurodegenerative diseases. The phagocyte NADPH oxidase (NOX2) is critical for antimicrobial host defence. Chronic granulomatous disease (CGD) is an inherited disorder of NOX2 characterized by severe life-threatening bacterial and fungal infections and by excessive inflammation, including Crohn's-like inflammatory bowel disease (IBD). NOX2 defends against microbes through the direct antimicrobial activity of reactive oxidants and through activation of granular proteases and generation of neutrophil extracellular traps (NETs). NETosis involves the breakdown of cell membranes and extracellular release of chromatin and neutrophil granular constituents that target extracellular pathogens. Although the immediate effects of oxidant generation and NETosis are predicted to be injurious, NOX2, in several contexts, limits inflammation and injury by modulation of key signalling pathways that affect neutrophil accumulation and clearance. NOX2 also plays a role in antigen presentation and regulation of adaptive immunity. Specific NOX2-activated pathways such as nuclear factor erythroid 2-related factor 2 (Nrf2), a transcriptional factor that induces antioxidative and cytoprotective responses, may be important therapeutic targets for CGD and, more broadly, diseases associated with excessive inflammation and injury.

  3. TRPC6 channel translocation into phagosomal membrane augments phagosomal function

    Science.gov (United States)

    Riazanski, Vladimir; Gabdoulkhakova, Aida G.; Boynton, Lin S.; Eguchi, Raphael R.; Deriy, Ludmila V.; Hogarth, D. Kyle; Loaëc, Nadège; Oumata, Nassima; Galons, Hervé; Brown, Mary E.; Shevchenko, Pavel; Gallan, Alexander J.; Yoo, Sang Gune; Naren, Anjaparavanda P.; Villereal, Mitchel L.; Beacham, Daniel W.; Bindokas, Vytautas P.; Birnbaumer, Lutz; Meijer, Laurent; Nelson, Deborah J.

    2015-01-01

    Defects in the innate immune system in the lung with attendant bacterial infections contribute to lung tissue damage, respiratory insufficiency, and ultimately death in the pathogenesis of cystic fibrosis (CF). Professional phagocytes, including alveolar macrophages (AMs), have specialized pathways that ensure efficient killing of pathogens in phagosomes. Phagosomal acidification facilitates the optimal functioning of degradative enzymes, ultimately contributing to bacterial killing. Generation of low organellar pH is primarily driven by the V-ATPases, proton pumps that use cytoplasmic ATP to load H+ into the organelle. Critical to phagosomal acidification are various channels derived from the plasma membrane, including the anion channel cystic fibrosis transmembrane conductance regulator, which shunt the transmembrane potential generated by movement of protons. Here we show that the transient receptor potential canonical-6 (TRPC6) calcium-permeable channel in the AM also functions to shunt the transmembrane potential generated by proton pumping and is capable of restoring microbicidal function to compromised AMs in CF and enhancement of function in non-CF cells. TRPC6 channel activity is enhanced via translocation to the cell surface (and then ultimately to the phagosome during phagocytosis) in response to G-protein signaling activated by the small molecule (R)-roscovitine and its derivatives. These data show that enhancing vesicular insertion of the TRPC6 channel to the plasma membrane may represent a general mechanism for restoring phagosome activity in conditions, where it is lost or impaired. PMID:26604306

  4. CFTR RECRUITMENT TO PHAGOSOMES IN NEUTROPHILS

    OpenAIRE

    Zhou, Yun; Song, Kejing; Painter, Richard G.; Aiken, Martha; Reiser, Jakob; Stanton, Bruce A.; Nauseef, William M.; Wang, Guoshun

    2013-01-01

    Optimal microbicidal activity of human polymorphonuclear leukocytes (PMN) relies on generation of toxic agents such as hypochlorous acid (HOCl) in phagosomes. HOCl formation requires H2O2 produced by the NADPH oxidase, myeloperoxidase derived from azurophilic granules, and chloride ion. Chloride transport from cytoplasm into phagosomes requires chloride channels which include cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated chloride channel. However, the phagosomal...

  5. Bacillus anthracis factors for phagosomal escape.

    Science.gov (United States)

    Tonello, Fiorella; Zornetta, Irene

    2012-07-01

    The mechanism of phagosome escape by intracellular pathogens is an important step in the infectious cycle. During the establishment of anthrax, Bacillus anthracis undergoes a transient intracellular phase in which spores are engulfed by local phagocytes. Spores germinate inside phagosomes and grow to vegetative bacilli, which emerge from their resident intracellular compartments, replicate and eventually exit from the plasma membrane. During germination, B. anthracis secretes multiple factors that can help its resistance to the phagocytes. Here the possible role of B. anthracis toxins, phospholipases, antioxidant enzymes and capsules in the phagosomal escape and survival, is analyzed and compared with that of factors of other microbial pathogens involved in the same type of process.

  6. Nox2 and Cyclosporine-Induced Renal Hypoxia.

    Science.gov (United States)

    Djamali, Arjang; Wilson, Nancy A; Sadowski, Elizabeth A; Zha, Wei; Niles, David; Hafez, Omeed; Dorn, Justin R; Mehner, Thomas R; Grimm, Paul C; Hoffmann, F Michael; Zhong, Weixiong; Fain, Sean B; Reese, Shannon R

    2016-06-01

    We hypothesized that nicotinamide adenosine diphosphate oxidase 2 (Nox2) plays an important role in cyclosporine A (CsA)-induced chronic hypoxia. We tested this hypothesis in Fisher 344 rats, C57BL/6 J wild type and Nox2-/- mice, and in liver transplant recipients with chronic CsA nephrotoxicity. We used noninvasive molecular imaging (blood oxygen level-dependent magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging) and molecular diagnostic tools to assess intrarenal oxygenation and perfusion, and the molecular phenotype of CsA nephrotoxicity. We observed that chemical and genetic inhibition of Nox2 in rats and mice resulted in the prevention of CsA-induced hypoxia independent of regional perfusion (blood oxygen level-dependent magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging, pimonidazole, HIF-1α). Nicotinamide adenosine diphosphate oxidase 2 knockout was also associated with decreased oxidative stress (Nox2, HIF-1α, hydrogen peroxide, hydroxynonenal), and fibrogenesis (α-smooth muscle actin, picrosirius red, trichrome, vimentin). The molecular signature of chronic CsA nephrotoxicity using transcriptomic analyses demonstrated significant changes in 40 genes involved in injury repair, metabolism, and oxidative stress in Nox2-/- mice. Immunohistochemical analyses of kidney biopsies from liver transplant recipients with chronic CsA nephrotoxicity showed significantly greater Nox2, α-smooth muscle actin and picrosirius levels compared with controls. These studies suggest that Nox2 is a modulator of CsA-induced hypoxia upstream of HIF-1α and define the molecular characteristics that could be used for the diagnosis and monitoring of chronic calcineurin inhibitor nephrotoxicity.

  7. Molecular characterization of the evolution of phagosomes

    OpenAIRE

    Boulais, Jonathan; Trost, Matthias; Landry, Christian R; Dieckmann, Régis; Levy, Emmanuel D.; Soldati, Thierry; Michnick, Stephen W.; Thibault, Pierre; Desjardins, Michel

    2010-01-01

    Phagocytosis is the process by which multiple cell types internalize large particulate material from the external milieu. The functional properties of phagosomes are acquired through a complex maturation process, referred to as phagolysosome biogenesis. This pathway involves a series of rapid interactions with organelles of the endocytic apparatus, enabling the gradual transformation of newly formed phagosomes into phagolysosomes in which proteolytic degradation occurs. The degradative enviro...

  8. Brucella suis-Impaired Specific Recognition of Phagosomes by Lysosomes due to Phagosomal Membrane Modifications

    Science.gov (United States)

    Naroeni, Aroem; Jouy, Nicolas; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre; Porte, Françoise

    2001-01-01

    Brucella species are gram-negative, facultatively intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment in phagocytic and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both types of cells. However, the biochemical mechanisms and microbial factors implicated in Brucella maturation are still completely unknown. We developed two different approaches in an attempt to gain further insight into these mechanisms: (i) a fluorescence microscopy analysis of general intracellular trafficking on whole cells in the presence of Brucella and (ii) a flow cytometry analysis of in vitro reconstitution assays showing the interaction between Brucella suis-containing phagosomes and lysosomes. The fluorescence microscopy results revealed that fusion properties of latex bead-containing phagosomes with lysosomes were not modified in the presence of live Brucella suis in the cells. We concluded that fusion inhibition was restricted to the pathogen phagosome and that the host cell fusion machinery was not altered by the presence of live Brucella in the cell. By in vitro reconstitution experiments, we observed a specific association between killed B. suis-containing phagosomes and lysosomes, which was dependent on exogenously supplied cytosol, energy, and temperature. This association was observed with killed bacteria but not with live bacteria. Hence, this specific recognition inhibition seemed to be restricted to the pathogen phagosomal membrane, as noted in the in vivo experiments. PMID:11119541

  9. Assessing the Phagosome Proteome by Quantitative Mass Spectrometry.

    Science.gov (United States)

    Peltier, Julien; Härtlova, Anetta; Trost, Matthias

    2017-01-01

    Phagocytosis is the process that engulfs particles in vesicles called phagosomes that are trafficked through a series of maturation steps, culminating in the destruction of the internalized cargo. Because phagosomes are in direct contact with the particle and undergo constant fusion and fission events with other organelles, characterization of the phagosomal proteome is a powerful tool to understand mechanisms controlling innate immunity as well as vesicle trafficking. The ability to isolate highly pure phagosomes through the use of latex beads led to an extensive use of proteomics to study phagosomes under different stimuli. Thousands of different proteins have been identified and quantified, revealing new properties and shedding new light on the dynamics and composition of maturing phagosomes and innate immunity mechanisms. In this chapter, we describe how quantitative-based proteomic methods such as label-free, dimethyl labeling or Tandem Mass Tag (TMT) labeling can be applied for the characterization of protein composition and translocation during maturation of phagosomes in macrophages.

  10. Membrane proteomics of phagosomes suggests a connection to autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Shui, Wenqing; Sheu, Leslie; Liu, Jun; Smart, Brian; Petzold, Christopher J.; Hsieh, Tsung-yen; Pitcher, Austin; Keasling*, Jay D.; Bertozzi*, Carolyn R.

    2008-11-25

    Phagocytosis is the central process by which macrophage cellsinternalize and eliminate infectious microbes as well as apoptoticcells. During maturation, phagosomes containing engulfed particlesfuse with various endosomal compartments through theaction of regulatory molecules on the phagosomal membrane. Inthis study, we performed a proteomic analysis of the membranefraction from latex bead-containing (LBC) phagosomes isolatedfrom macrophages. The profile, which comprised 546 proteins,suggests diverse functions of the phagosome and potential connectionsto secretory processes, toll-like receptor signaling, andautophagy. Many identified proteins were not previously knownto reside in the phagosome. We characterized several proteins inLBC phagosomes that change in abundance on induction of autophagy,a process that has been previously implicated in the hostdefense against microbial pathogens. These observations suggestcrosstalk between autophagy and phagocytosis that may be relevantto the innate immune response of macrophages.

  11. NOX2 protects against progressive lung injury and multiple organ dysfunction syndrome.

    Science.gov (United States)

    Whitmore, Laura C; Goss, Kelli L; Newell, Elizabeth A; Hilkin, Brieanna M; Hook, Jessica S; Moreland, Jessica G

    2014-07-01

    Systemic inflammatory response syndrome (SIRS) is a common clinical condition in patients in intensive care units that can lead to complications, including multiple organ dysfunction syndrome (MODS). MODS carries a high mortality rate, and it is unclear why some patients resolve SIRS, whereas others develop MODS. Although oxidant stress has been implicated in the development of MODS, several recent studies have demonstrated a requirement for NADPH oxidase 2 (NOX2)-derived oxidants in limiting inflammation. We recently demonstrated that NOX2 protects against lung injury and mortality in a murine model of SIRS. In the present study, we investigated the role of NOX2-derived oxidants in the progression from SIRS to MODS. Using a murine model of sterile systemic inflammation, we observed significantly greater illness and subacute mortality in gp91(phox-/y) (NOX2-deficient) mice compared with wild-type mice. Cellular analysis revealed continued neutrophil recruitment to the peritoneum and lungs of the NOX2-deficient mice and altered activation states of both neutrophils and macrophages. Histological examination showed multiple organ pathology indicative of MODS in the NOX2-deficient mice, and several inflammatory cytokines were elevated in lungs of the NOX2-deficient mice. Overall, these data suggest that NOX2 function protects against the development of MODS and is required for normal resolution of systemic inflammation. Copyright © 2014 the American Physiological Society.

  12. Mechanism of inducible nitric oxide synthase exclusion from mycobacterial phagosomes.

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    Alexander S Davis

    2007-12-01

    Full Text Available Mycobacterium tuberculosis is sensitive to nitric oxide generated by inducible nitric oxide synthase (iNOS. Consequently, to ensure its survival in macrophages, M. tuberculosis inhibits iNOS recruitment to its phagosome by an unknown mechanism. Here we report the mechanism underlying this process, whereby mycobacteria affect the scaffolding protein EBP50, which normally binds to iNOS and links it to the actin cytoskeleton. Phagosomes harboring live mycobacteria showed reduced capacity to retain EBP50, consistent with lower iNOS recruitment. EBP50 was found on purified phagosomes, and its expression increased upon macrophage activation, paralleling expression changes seen with iNOS. Overexpression of EBP50 increased while EBP50 knockdown decreased iNOS recruitment to phagosomes. Knockdown of EBP50 enhanced mycobacterial survival in activated macrophages. We tested another actin organizer, coronin-1, implicated in mycobacterium-macrophage interaction for contribution to iNOS exclusion. A knockdown of coronin-1 resulted in increased iNOS recruitment to model latex bead phagosomes but did not increase iNOS recruitment to phagosomes with live mycobacteria and did not affect mycobacterial survival. Our findings are consistent with a model for the block in iNOS association with mycobacterial phagosomes as a mechanism dependent primarily on reduced EBP50 recruitment.

  13. Nox2 Mediates Skeletal Muscle Insulin Resistance Induced by a High Fat Diet*

    Science.gov (United States)

    Souto Padron de Figueiredo, Alvaro; Salmon, Adam B.; Bruno, Francesca; Jimenez, Fabio; Martinez, Herman G.; Halade, Ganesh V.; Ahuja, Seema S.; Clark, Robert A.; DeFronzo, Ralph A.; Abboud, Hanna E.; El Jamali, Amina

    2015-01-01

    Inflammation and oxidative stress through the production of reactive oxygen species (ROS) are consistently associated with metabolic syndrome/type 2 diabetes. Although the role of Nox2, a major ROS-generating enzyme, is well described in host defense and inflammation, little is known about its potential role in insulin resistance in skeletal muscle. Insulin resistance induced by a high fat diet was mitigated in Nox2-null mice compared with wild-type mice after 3 or 9 months on the diet. High fat feeding increased Nox2 expression, superoxide production, and impaired insulin signaling in skeletal muscle tissue of wild-type mice but not in Nox2-null mice. Exposure of C2C12 cultured myotubes to either high glucose concentration, palmitate, or H2O2 decreases insulin-induced Akt phosphorylation and glucose uptake. Pretreatment with catalase abrogated these effects, indicating a key role for H2O2 in mediating insulin resistance. Down-regulation of Nox2 in C2C12 cells by shRNA prevented insulin resistance induced by high glucose or palmitate but not H2O2. These data indicate that increased production of ROS in insulin resistance induced by high glucose in skeletal muscle cells is a consequence of Nox2 activation. This is the first report to show that Nox2 is a key mediator of insulin resistance in skeletal muscle. PMID:25825489

  14. INF-γ Enhances Nox2 Activity by Upregulating phox Proteins When Applied to Differentiating PLB-985 Cells but Does Not Induce Nox2 Activity by Itself.

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    Michael A Ellison

    Full Text Available The cytokine and drug interferon-γ enhances superoxide anion production by the antimicrobicidal Nox2 enzyme of neutrophils. Because mature neutrophils have a short lifespan, we hypothesized that the effects of interferon-γ on these cells might be mediated by its prolonged exposure to differentiating neutrophil precursors in the bone marrow rather than its brief exposure to mature circulating neutrophils. Effects of INF-Γ on NOX2 activity: To address this possibility we exposed the myeloid PLB-985 cell line to interferon-γ for 3 days in the presence of dimethyl sulfoxide which induces terminal differentiation of these cells. Interferon-γ was found to enhance superoxide production by Nox2 in a concentration dependent manner. In contrast, application of interferon-γ alone for 3 days failed to induce detectible Nox2 activity. Additionally, application of interferon-γ for 3 hours to pre-differentiated PLB-985 cells, which models studies using isolated neutrophils, was much less effective at enhancing superoxide anion production. Effects of INF-Γ on phox protein levels: Addition of interferon-γ during differentiation was found to upregulate the Nox2 proteins gp91phox and p47phox in concert with elevated transcription of their genes. The p22phox protein was upregulated in the absence of increased transcription presumably reflecting stabilization resulting from binding to the elevated gp91phox. Thus, increased levels of gp91phox, p47phox and p22phox likely account for the interferon-γ mediated enhancement of dimethyl sulfoxide-induced Nox2 activity. In contrast, although interferon-γ alone also increased various phox proteins and their mRNAs, the pattern was very different to that seen with interferon-γ plus dimethyl sulfoxide. In particular, p47phox was not induced thus explaining the inability of interferon -γ alone to enhance Nox2 activity. Short application of interferon-γ to already differentiated cells failed to increase any phox

  15. Protein chlorination in neutrophil phagosomes and correlation with bacterial killing.

    Science.gov (United States)

    Green, Jessie N; Kettle, Anthony J; Winterbourn, Christine C

    2014-12-01

    Neutrophils ingest and kill bacteria within phagocytic vacuoles. We investigated where they produce hypochlorous acid (HOCl) following phagocytosis by measuring conversion of protein tyrosine residues to 3-chlorotyrosine. We also examined how varying chloride availability affects the relationship between HOCl formation in the phagosome and bacterial killing. Phagosomal proteins, isolated following ingestion of opsonized magnetic beads, contained 11.4 Cl-Tyr per thousand tyrosine residues. This was 12 times higher than the level in proteins from the rest of the neutrophil and ~6 times higher than previously recorded for protein from ingested bacteria. These results indicate that HOCl production is largely localized to the phagosomes and a substantial proportion reacts with phagosomal protein before reaching the microbe. This will in part detoxify the oxidant but should also form chloramines which could contribute to the killing mechanism. Neutrophils were either suspended in chloride-free gluconate buffer or pretreated with formyl-Met-Leu-Phe, a procedure that has been reported to deplete intracellular chloride. These treatments, alone or in combination, decreased both chlorination in phagosomes and killing of Staphylococcus aureus by up to 50%. There was a strong positive correlation between the two effects. Killing was predominantly oxidant and myeloperoxidase dependent (88% inhibition by diphenylene iodonium and 78% by azide). These results imply that lowering the chloride concentration limits HOCl production and oxidative killing. They support a role for HOCl generation, rather than an alternative myeloperoxidase activity, in the killing process.

  16. Bacillus anthracis Factors for Phagosomal Escape

    Directory of Open Access Journals (Sweden)

    Irene Zornetta

    2012-07-01

    Full Text Available The mechanism of phagosome escape by intracellular pathogens is an important step in the infectious cycle. During the establishment of anthrax, Bacillus anthracis undergoes a transient intracellular phase in which spores are engulfed by local phagocytes. Spores germinate inside phagosomes and grow to vegetative bacilli, which emerge from their resident intracellular compartments, replicate and eventually exit from the plasma membrane. During germination, B. anthracis secretes multiple factors that can help its resistance to the phagocytes. Here the possible role of B. anthracis toxins, phospholipases, antioxidant enzymes and capsules in the phagosomal escape and survival, is analyzed and compared with that of factors of other microbial pathogens involved in the same type of process.

  17. Helicobacter pylori phagosome maturation in primary human macrophages

    Directory of Open Access Journals (Sweden)

    Borlace Glenn N

    2011-03-01

    Full Text Available Abstract Background Helicobacter pylori (H. pylori is a micro-aerophilic, spiral-shaped, motile bacterium that is the principal cause of gastric and duodenal ulcers in humans and is a major risk factor for the development of gastric cancer. Despite provoking a strong innate and adaptive immune response in the host, H. pylori persists in the gastric mucosa, avoiding eradication by macrophages and other phagocytic cells, which are recruited to the site of infection. Here we have characterised the critical degradative process of phagosome maturation in primary human macrophages for five genotypically and phenotypically distinct clinical strains of H. pylori. Results All of the H. pylori strains examined showed some disruption to the phagosome maturation process, when compared to control E. coli. The early endosome marker EEA1 and late endosome marker Rab7 were retained on H. pylori phagosomes, while the late endosome-lysosome markers CD63, LAMP-1 and LAMP-2 were acquired in an apparently normal manner. Acquisition of EEA1 by H. pylori phagosomes appeared to occur by two distinct, strain specific modes. H. pylori strains that were negative for the cancer associated virulence factor CagA were detected in phagosomes that recruited large amounts of EEA1 relative to Rab5, compared to CagA positive strains. There were also strain specific differences in the timing of Rab7 acquisition which correlated with differences in the rate of intracellular trafficking of phagosomes and the timing of megasome formation. Megasomes were observed for all of the H. pylori strains examined. Conclusions H. pylori appeared to disrupt the normal process of phagosome maturation in primary human macrophages, appearing to block endosome fission. This resulted in the formation of a hybrid phagosome-endosome-lysosome compartment, which we propose has reduced degradative capacity. Reduced killing by phagocytes is consistent with the persistence of H. pylori in the host, and would

  18. DMPD: Linking inflammasome activation and phagosome maturation. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18407061 Linking inflammasome activation and phagosome maturation. Lazarevic V, Mar...tinon F. Cell Host Microbe. 2008 Apr 17;3(4):199-200. (.png) (.svg) (.html) (.csml) Show Linking inflammasome activation... and phagosome maturation. PubmedID 18407061 Title Linking inflammasome activation and phagosome

  19. NOX2 inhibition impairs early muscle gene expression induced by a single exercise bout

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    Carlos Henríquez-Olguín

    2016-07-01

    Full Text Available Reactive oxygen species (ROS participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2 in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg or vehicle for 3 days, were swim-exercised for 60 min. Phospho-p47phox levels were significantly upregulated by exercise in flexor digitorum brevis (FDB. Moreover, exercise significantly increased NOX2 complex assembly (p47phox-gp91phox interaction demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD, glutathione peroxidase (GPx, citrate synthase (CS, mitochondrial transcription factor A (tfam and interleukin-6 (IL-6 in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p<0.001. These results were corroborated using gp91-dstat in an in-vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise.

  20. NOX2 Inhibition Impairs Early Muscle Gene Expression Induced by a Single Exercise Bout.

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    Henríquez-Olguín, Carlos; Díaz-Vegas, Alexis; Utreras-Mendoza, Yildy; Campos, Cristian; Arias-Calderón, Manuel; Llanos, Paola; Contreras-Ferrat, Ariel; Espinosa, Alejandra; Altamirano, Francisco; Jaimovich, Enrique; Valladares, Denisse M

    2016-01-01

    Reactive oxygen species (ROS) participate as signaling molecules in response to exercise in skeletal muscle. However, the source of ROS and the molecular mechanisms involved in these phenomena are still not completely understood. The aim of this work was to study the role of skeletal muscle NADPH oxidase isoform 2 (NOX2) in the molecular response to physical exercise in skeletal muscle. BALB/c mice, pre-treated with a NOX2 inhibitor, apocynin, (3 mg/kg) or vehicle for 3 days, were swim-exercised for 60 min. Phospho-p47(phox) levels were significantly upregulated by exercise in flexor digitorum brevis (FDB). Moreover, exercise significantly increased NOX2 complex assembly (p47(phox)-gp91(phox) interaction) demonstrated by both proximity ligation assay and co-immunoprecipitation. Exercise-induced NOX2 activation was completely inhibited by apocynin treatment. As expected, exercise increased the mRNA levels of manganese superoxide dismutase (MnSOD), glutathione peroxidase (GPx), citrate synthase (CS), mitochondrial transcription factor A (tfam) and interleukin-6 (IL-I6) in FDB muscles. Moreover, the apocynin treatment was associated to a reduced activation of p38 MAP kinase, ERK 1/2, and NF-κB signaling pathways after a single bout of exercise. Additionally, the increase in plasma IL-6 elicited by exercise was decreased in apocynin-treated mice compared with the exercised vehicle-group (p < 0.001). These results were corroborated using gp91-dstat in an in vitro exercise model. In conclusion, NOX2 inhibition by both apocynin and gp91dstat, alters the intracellular signaling to exercise and electrical stimuli in skeletal muscle, suggesting that NOX2 plays a critical role in molecular response to an acute exercise.

  1. Phosphoinositol 3-phosphate acts as a timer for reactive oxygen species production in the phagosome.

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    Song, Zhi Min; Bouchab, Leïla; Hudik, Elodie; Le Bars, Romain; Nüsse, Oliver; Dupré-Crochet, Sophie

    2017-05-01

    Production of reactive oxygen species (ROS) in the phagosome by the NADPH oxidase is critical for mammalian immune defense against microbial infections and phosphoinositides are important regulators in this process. Phosphoinositol 3-phosphate (PI(3)P) regulates ROS production at the phagosome via p40(phox) by an unknown mechanism. This study tested the hypothesis that PI(3)P controls ROS production by regulating the presence of p40(phox) and p67(phox) at the phagosomal membrane. Pharmacologic inhibition of PI(3)P synthesis at the phagosome decreased the ROS production both in differentiated PLB-985 cells and human neutrophils. It also releases p67(phox), the key cytosolic subunit of the oxidase, and p40(phox) from the phagosome. The knockdown of the PI(3)P phosphatase MTM1 or Rubicon or both increases the level of PI(3)P at the phagosome. That increase enhances ROS production inside the phagosome and triggers an extended accumulation of p67(phox) at the phagosome. Furthermore, the overexpression of MTM1 at the phagosomal membrane induces the disappearance of PI(3)P from the phagosome and prevents sustained ROS production. In conclusion, PI(3)P, indeed, regulates ROS production by maintaining p40(phox) and p67(phox) at the phagosomal membrane. © Society for Leukocyte Biology.

  2. NOX2 amplifies acetaldehyde-mediated cardiomyocyte mitochondrial dysfunction in alcoholic cardiomyopathy

    Science.gov (United States)

    Brandt, Moritz; Garlapati, Venkata; Oelze, Matthias; Sotiriou, Efthymios; Knorr, Maike; Kröller-Schön, Swenja; Kossmann, Sabine; Schönfelder, Tanja; Morawietz, Henning; Schulz, Eberhard; Schultheiss, Heinz-Peter; Daiber, Andreas; Münzel, Thomas; Wenzel, Philip

    2016-01-01

    Alcoholic cardiomyopathy (ACM) resulting from excess alcohol consumption is an important cause of heart failure (HF). Although it is assumed that the cardiotoxicity of the ethanol (EtOH)-metabolite acetaldehyde (ACA) is central for its development and progression, the exact mechanisms remain obscure. Murine cardiomyocytes (CMs) exposed to ACA or EtOH showed increased superoxide (O2•−) levels and decreased mitochondrial polarization, both being normalized by NADPH oxidase (NOX) inhibition. C57BL/6 mice and mice deficient for the ACA-degrading enzyme mitochondrial aldehyde dehydrogenase (ALDH-2−/−) were fed a 2% EtOH diet for 5 weeks creating an ACA-overload. 2% EtOH-fed ALDH-2−/− mice exhibited a decreased cardiac function, increased heart-to-body and lung-to-body weight ratios, increased cardiac levels of the lipid peroxidation product malondialdehyde (MDA) as well as increased NOX activity and NOX2/glycoprotein 91phox (NOX2/gp91phox) subunit expression compared to 2% EtOH-fed C57BL/6 mice. Echocardiography revealed that ALDH-2−/−/gp91phox−/− mice were protected from ACA-overload-induced HF after 5 weeks of 2% EtOH-diet, demonstrating that NOX2-derived O2•− contributes to the development of ACM. Translated to human pathophysiology, we found increased gp91phox expression in endomyocardial biopsies of ACM patients. In conclusion, ACM is promoted by ACA-driven mitochondrial dysfunction and can be improved by ablation of NOX2/gp91phox. NOX2/gp91phox therefore might be a potential pharmacological target to treat ACM. PMID:27624556

  3. Modelling phagosomal lipid networks that regulate actin assembly

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    Schwarz Roland

    2008-12-01

    Full Text Available Abstract Background When purified phagosomes are incubated in the presence of actin under appropriate conditions, microfilaments start growing from the membrane in a process that is affected by ATP and the lipid composition of the membrane. Isolated phagosomes are metabolically active organelles that contain enzymes and metabolites necessary for lipid interconversion. Hence, addition of ATP, lipids, and actin to the system alter the steady-state composition of the phagosomal membrane at the same time that the actin nucleation is initiated. Our aim was to model all these processes in parallel. Results We compiled detailed experimental data on the effects of different lipids and ATP on actin nucleation and we investigated experimentally lipid interconversion and ATP metabolism in phagosomes by using suitable radioactive compounds. In a first step, a complex lipid network interconnected by chemical reactions catalyzed by known enzymes was modelled in COPASI (Complex Pathway Simulator. However, several lines of experimental evidence indicated that only the phosphatidylinositol branch of the network was active, an observation that dramatically reduced the number of parameters in the model. The results also indicated that a lipid network-independent ATP-consuming activity should be included in the model. When this activity was introduced, the set of differential equations satisfactorily reproduced the experimental data. On the other hand, a molecular mechanism connecting membrane lipids, ATP, and the actin nucleation process is still missing. We therefore adopted a phenomenological (black-box approach to represent the empirical observations. We proposed that lipids and ATP influence the dynamic interconversion between active and inactive actin nucleation sites. With this simple model, all the experimental data were satisfactorily fitted with a single positive parameter per lipid and ATP. Conclusion By establishing an active 'dialogue' between an

  4. The Phosphoinositide-Gated Lysosomal Ca(2+) Channel, TRPML1, Is Required for Phagosome Maturation.

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    Dayam, Roya M; Saric, Amra; Shilliday, Ryan E; Botelho, Roberto J

    2015-09-01

    Macrophages internalize and sequester pathogens into a phagosome. Phagosomes then sequentially fuse with endosomes and lysosomes, converting into degradative phagolysosomes. Phagosome maturation is a complex process that requires regulators of the endosomal pathway including the phosphoinositide lipids. Phosphatidylinositol-3-phosphate and phosphatidylinositol-3,5-bisphosphate (PtdIns(3,5)P2 ), which respectively control early endosomes and late endolysosomes, are both required for phagosome maturation. Inhibition of PIKfyve, which synthesizes PtdIns(3,5)P2 , blocked phagosome-lysosome fusion and abated the degradative capacity of phagosomes. However, it is not known how PIKfyve and PtdIns(3,5)P2 participate in phagosome maturation. TRPML1 is a PtdIns(3,5)P2 -gated lysosomal Ca(2+) channel. Because Ca(2+) triggers membrane fusion, we postulated that TRPML1 helps mediate phagosome-lysosome fusion. Using Fcγ receptor-mediated phagocytosis as a model, we describe our research showing that silencing of TRPML1 hindered phagosome acquisition of lysosomal markers and reduced the bactericidal properties of phagosomes. Specifically, phagosomes isolated from TRPML1-silenced cells were decorated with lysosomes that docked but did not fuse. We could rescue phagosome maturation in TRPML1-silenced and PIKfyve-inhibited cells by forcible Ca(2+) release with ionomycin. We also provide evidence that cytosolic Ca(2+) concentration increases upon phagocytosis in a manner dependent on TRPML1 and PIKfyve. Overall, we propose a model where PIKfyve and PtdIns(3,5)P2 activate TRPML1 to induce phagosome-lysosome fusion.

  5. Voltage-gated proton channel is expressed on phagosomes.

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    Okochi, Yoshifumi; Sasaki, Mari; Iwasaki, Hirohide; Okamura, Yasushi

    2009-05-01

    Voltage-gated proton channel has been suggested to help NADPH oxidase activity during respiratory burst of phagocytes through its activities of compensating charge imbalance and regulation of pH. In phagocytes, robust production of reactive oxygen species occurs in closed membrane compartments, which are called phagosomes. However, direct evidence for the presence of voltage-gated proton channels in phagosome has been lacking. In this study, the expression of voltage-gated proton channels was studied by Western blot with the antibody specific to the voltage-sensor domain protein, VSOP/Hv1, that has recently been identified as the molecular correlate for the voltage-gated proton channel. Phagosomal membranes of neutrophils contain VSOP/Hv1 in accordance with subunits of NADPH oxidases, gp91, p22, p47 and p67. Superoxide anion production upon PMA activation was significantly reduced in neutrophils from VSOP/Hv1 knockout mice. These are consistent with the idea that voltage-gated proton channels help NADPH oxidase in phagocytes to produce reactive oxygen species.

  6. Prostanoid-mediated contractions of the carotid artery become Nox2-independent with aging.

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    Meyer, Matthias R; Fredette, Natalie C; Barton, Matthias; Prossnitz, Eric R

    2015-08-01

    Aging is a major risk factor for carotid artery disease that may lead to stroke and dementia. Vascular effects associated with aging include increased vasomotor tone, as well as enhanced contractility to endothelial vasoconstrictor prostanoids and reduced nitric oxide (NO) bioactivity partly due to increased oxidative stress. We hypothesized that vascular NADPH oxidase (Nox)-derived superoxide may be involved in prostanoid- and NO-related functional aging. NO-mediated relaxations and prostanoid-mediated contractions to acetylcholine as well as phenylephrine-dependent contractions were investigated in the carotid artery from young (4 months) and aged mice (24 months). Gene expression of Nox subunits and endothelial NO synthase (eNOS) was determined in the carotid artery and aorta. In young mice, the thromboxane-prostanoid receptor antagonist SQ 29,548 fully blocked acetylcholine-induced contractions while reducing responses to phenylephrine by 75 %. The Nox2-targeted inhibitor Nox2ds-tat and the superoxide scavenger tempol reduced acetylcholine-stimulated, prostanoid-mediated contractions by 85 and 75 %, respectively, and phenylephrine-dependent contractions by 45 %. Unexpectedly, in aged mice, the substantial Nox2-dependent component of acetylcholine- and phenylephrine-induced, prostanoid-mediated contractions was abolished. In addition, endothelium-dependent, NO-mediated relaxations were impaired with aging. The expression of Nox subunits was greater in the aorta compared with the carotid artery, in which Nox1 was undetectable. eNOS gene expression was reduced in the aorta of aged compared to young mice. In conclusion, aging decreases prostanoid-mediated contractility in the carotid artery involving a loss of Nox2 activity and is associated with impaired endothelium-dependent, NO-mediated relaxation. These findings may contribute to a better understanding of the pathophysiology of carotid artery disease and the aging process.

  7. Monitoring time-dependent maturation changes in purified phagosomes from Dictyostelium discoideum.

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    Dieckmann, Régis; Gopaldass, Navin; Escalera, Caroline; Soldati, Thierry

    2008-01-01

    The amoeba Dictyostelium discoideum is an established model to study phagocytosis. The sequence of events leading to the internalization and degradation of a particle is conserved in D. discoideum compared to metazoan cells. As its small haploid genome has been sequenced, it is now amenable to genome-wide analysis including organelle proteomics. Therefore, we adapted to Dictyostelium the classical protocol to purify phagosomes formed by ingestion of latex beads particles. The pulse-chase protocol detailed here gives easy access to pure, intact, and synchronized phagosomes from representative stages of the entire process of phagosome maturation. Recently, this protocol was used to generate individual temporal profiles of proteins and lipids during phagosome maturation generating a proteomic fingerprint of six maturation stages (1). In addition, immunolabeling of phagosomes on a coverslip was developed to visualize and quantitate antigen distribution at the level of individual phagosomes.

  8. New Insights into the Steen Solution Properties: Breakthrough in Antioxidant Effects via NOX2 Downregulation

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    Roberto Carnevale

    2014-01-01

    Full Text Available Ex vivo lung perfusion (EVLP allows perfusion and reconditioning of retrieved lungs for organ transplantation. The Steen solution is specifically designed for this procedure but the mechanism through which it elicits its activity is still to be fully clarified. We speculated that Steen solution may encompass antioxidant properties allowing a reestablishment of pulmonary tissue homeostasis. Blood samples from 10 healthy volunteers were recruited. Platelets and white cells were incubated with Steen solution or buffer solution as control and stimulated with suitable agonists. Reactive oxidant species (ROS, soluble NOX2 (sNOX2-derived peptide, a marker of NADPH oxidase activation, p47phox translocation to cell membrane and isoprostanes production, as marker of oxidative stress, and nitric oxide (NO, a powerful vasodilator and antioxidant molecule, were measured upon cell stimulation. The Steen solution significantly inhibited p47phox translocation and NOX2 activation in platelets and white cells. Consistent with this finding was the reduction of oxidative stress as documented by a significantly lowered formation of ROS and isoprostanes by both platelets and white cells. Finally, cell incubation with Steen solution resulted in enhanced generation of NO. Herewith, we provide the first evidence that Steen solution possesses antioxidant properties via downregulation of NADPH oxidase activity and enhanced production of NO.

  9. Effects of dark chocolate on NOX-2-generated oxidative stress in patients with non-alcoholic steatohepatitis.

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    Loffredo, L; Del Ben, M; Perri, L; Carnevale, R; Nocella, C; Catasca, E; Baratta, F; Ceci, F; Polimeni, L; Gozzo, P; Violi, F; Angelico, F

    2016-08-01

    Activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is considered a pathogenetic mechanism determining fibrosis and disease progression in non-alcoholic steatohepatitis (NASH). Polyphenols exert antioxidant action and inhibit NADPH oxidase in humans. To analyse the effect of cocoa polyphenols on NADPH oxidase isoform 2 (NOX2) activation, oxidative stress and hepatocyte apoptosis in a population affected by NASH. In a cross-sectional study comparing 19 NASH and 19 controls, oxidative stress, as assessed by serum NOX2 activity and F2-isoprostanes, and hepatocyte apoptosis, as assessed by serum cytokeratin-18 (CK-18) levels, were measured. Furthermore, the 19 NASH patients were randomly allocated in a crossover design to 40 g/day of dark chocolate (>85% cocoa) or 40 g/day of milk chocolate (chocolate intake. Compared to controls, NASH patients had higher sNOX2-dp, serum isoprostanes and CK-18 levels. A significant difference for treatments was found in subjects with respect to sNOX2-dp, serum isoprostanes and serum CK-18. The pairwise comparisons showed that, compared to baseline, after 14 days of dark chocolate intake, a significant reduction in sNOX2-dp serum isoprostanes and CK-18 M30 was found. No change was observed after milk chocolate ingestion. A simple linear regression analysis showed that ∆ of sNOX2-dp was associated with ∆ of serum isoprostanes. Cocoa polyphenols exert an antioxidant activity via NOX2 down-regulation in NASH patients. © 2016 John Wiley & Sons Ltd.

  10. Rab20 regulates phagosome maturation in RAW264 macrophages during Fc gamma receptor-mediated phagocytosis.

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    Youhei Egami

    Full Text Available Rab20, a member of the Rab GTPase family, is known to be involved in membrane trafficking, however its implication in FcγR-mediated phagocytosis is unclear. We examined the spatiotemporal localization of Rab20 during phagocytosis of IgG-opsonized erythrocytes (IgG-Es in RAW264 macrophages. By the live-cell imaging of fluorescent protein-fused Rab20, it was shown that Rab20 was transiently associated with the phagosomal membranes. During the early stage of phagosome formation, Rab20 was not localized on the membranes of phagocytic cups, but was gradually recruited to the newly formed phagosomes. Although Rab20 was colocalized with Rab5 to some extent, the association of Rab20 with the phagosomes persisted even after the loss of Rab5 from the phagosomal membranes. Then, Rab20 was colocalized with Rab7 and Lamp1, late endosomal/lysosomal markers, on the internalized phagosomes. Moreover, our analysis of Rab20 mutant expression revealed that the maturation of phagosomes was significantly delayed in cells expressing the GDP-bound mutant Rab20-T19N. These data suggest that Rab20 is an important component of phagosome and regulates the phagosome maturation during FcγR-mediated phagocytosis.

  11. Measuring Phagosomal pH by Fluorescence Microscopy.

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    Canton, Johnathan; Grinstein, Sergio

    2017-01-01

    Dual wavelength ratiometric imaging has become a powerful tool for the study of pH in intracellular compartments. It allows for the dynamic imaging of live cells while accounting for changes in the focal plane, differential loading of the fluorescent probe, and photobleaching caused by repeated image acquisitions. Ratiometric microscopic imaging has the added advantage over whole population methods of being able to resolve individual cells and even individual organelles. In this chapter we provide a detailed discussion of the basic principles of ratiometric imaging and its application to the measurement of phagosomal pH, including probe selection, the necessary instrumentation, and calibration methods.

  12. Dynein Clusters into Lipid Microdomains on Phagosomes to Drive Rapid Transport toward Lysosomes

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    Rai, Ashim; Pathak, Divya; Thakur, Shreyasi; Singh, Shampa; Dubey, Alok Kumar; Mallik, Roop

    2016-01-01

    Summary Diverse cellular processes are driven by motor proteins that are recruited to and generate force on lipid membranes. Surprisingly little is known about how membranes control the force from motors and how this may impact specific cellular functions. Here, we show that dynein motors physically cluster into microdomains on the membrane of a phagosome as it matures inside cells. Such geometrical reorganization allows many dyneins within a cluster to generate cooperative force on a single microtubule. This results in rapid directed transport of the phagosome toward microtubule minus ends, likely promoting phagolysosome fusion and pathogen degradation. We show that lipophosphoglycan, the major molecule implicated in immune evasion of Leishmania donovani, inhibits phagosome motion by disrupting the clustering and therefore the cooperative force generation of dynein. These findings appear relevant to several pathogens that prevent phagosome-lysosome fusion by targeting lipid microdomains on phagosomes. PMID:26853472

  13. Inhibition of NAPDH Oxidase 2 (NOX2 Prevents Oxidative Stress and Mitochondrial Abnormalities Caused by Saturated Fat in Cardiomyocytes.

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    Leroy C Joseph

    Full Text Available Obesity and high saturated fat intake increase the risk of heart failure and arrhythmias. The molecular mechanisms are poorly understood. We hypothesized that physiologic levels of saturated fat could increase mitochondrial reactive oxygen species (ROS in cardiomyocytes, leading to abnormalities of calcium homeostasis and mitochondrial function. We investigated the effect of saturated fat on mitochondrial function and calcium homeostasis in isolated ventricular myocytes. The saturated fatty acid palmitate causes a decrease in mitochondrial respiration in cardiomyocytes. Palmitate, but not the monounsaturated fatty acid oleate, causes an increase in both total cellular ROS and mitochondrial ROS. Palmitate depolarizes the mitochondrial inner membrane and causes mitochondrial calcium overload by increasing sarcoplasmic reticulum calcium leak. Inhibitors of PKC or NOX2 prevent mitochondrial dysfunction and the increase in ROS, demonstrating that PKC-NOX2 activation is also required for amplification of palmitate induced-ROS. Cardiomyocytes from mice with genetic deletion of NOX2 do not have palmitate-induced ROS or mitochondrial dysfunction. We conclude that palmitate induces mitochondrial ROS that is amplified by NOX2, causing greater mitochondrial ROS generation and partial depolarization of the mitochondrial inner membrane. The abnormal sarcoplasmic reticulum calcium leak caused by palmitate could promote arrhythmia and heart failure. NOX2 inhibition is a potential therapy for heart disease caused by diabetes or obesity.

  14. PVN adenovirus-siRNA injections silencing either NOX2 or NOX4 attenuate aldosterone/NaCl-induced hypertension in mice.

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    Xue, Baojian; Beltz, Terry G; Johnson, Ralph F; Guo, Fang; Hay, Meredith; Johnson, Alan Kim

    2012-02-01

    Mineralocorticoid excess increases superoxide production by activating NADPH oxidase (NOX), and intracerebroventricular infusions of NADPH oxidase inhibitors attenuate aldosterone (Aldo)/salt-induced hypertension. It has been hypothesized that increased reactive oxygen species (ROS) in the brain may be a key mechanism in the development of hypertension. The present study investigated the brain regional specificity of NADPH oxidase and the role of NOX2 and NOX4 NADPH oxidase subunits in the hypothalamic paraventricular nucleus (PVN) in Aldo/salt-induced hypertension. PVN injections of adenoviral vectors expressing small interfering (si)RNA targeting NOX2 (AdsiRNA-NOX2) or NOX4 (AdsiRNA-NOX4) mRNAs were used to knock down NOX2 and NOX4 proteins. Three days later, delivery of Aldo (0.2 mg·kg(-1)·day(-1) sc) via osmotic pump commenced and 1% NaCl was provided in place of water. PVN injections of either AdsiRNA-NOX2 or AdsiRNA-NOX4 significantly attenuated the development of Aldo/NaCl-induced hypertension. In an additional study, Aldo/salt-induced hypertension was also significantly attenuated in NOX2 (genomic) knockout mice compared with wild-type controls. When animals from both functional studies underwent ganglionic blockade, there was a reduced fall in blood pressure in the NOX2 and NOX4 knockdown/knockout mice. Western blot analyses of the PVN of siRNA-NOX2- or siRNA-NOX4-injected mice confirmed a marked reduction in the expression of NOX2 or NOX4 protein. In cultured PVN neurons, silencing either NOX2 or NOX4 protein production by culturing PVN cells with siRNA-NOX2 or siRNA-NOX4 attenuated Aldo-induced ROS. These data indicate that both NOX2 and NOX4 in the PVN contribute to elevated sympathetic activity and the hypertensivogenic actions induced by mineralocorticoid excess.

  15. NADPH oxidase NOX2 defines a new antagonistic role for reactive oxygen species and cAMP/PKA in the regulation of insulin secretion.

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    Li, Ning; Li, Bin; Brun, Thierry; Deffert-Delbouille, Christine; Mahiout, Zahia; Daali, Youssef; Ma, Xiao-Juan; Krause, Karl-Heinz; Maechler, Pierre

    2012-11-01

    In insulin-secreting cells, expression of NADPH oxidase (NOX), a potent source of ROS, has been reported, along with controversial findings regarding its function. Here, the role of NOXs was investigated: first by expression and cellular localization in mouse and human pancreatic islets, and then by functional studies in islets isolated from Nox isoform-specific knockout mice. Both human and mouse β-cells express NOX, in particular NOX2. With use of Nox isoform-specific knockout mice, functional analysis revealed Nox2 as the predominant isoform. In human islets, NOX2 colocalized with both insulin granules and endosome/lysosome membranes. Nox2-deficient islets stimulated with 22.8 mmol/L glucose exhibited potentiation of insulin release compared with controls, an effect confirmed with in vitro knockdown of Nox2. The enhanced secretory function in Nox2-deficient islets was associated with both lower superoxide levels and elevated cAMP concentrations. In control islets, GLP-1 and other cAMP inducers suppressed glucose-induced ROS production similarly to Nox2 deficiency. Inhibiting cAMP-dependent protein kinase reduced the secretory response in Nox2-null islets, although not in control islets. This study ascribes a new role for NOX2 in pancreatic β-cells as negative modulator of the secretory response, reducing cAMP/PKA signaling secondary to ROS generation. Results also show reciprocal inhibition between the cAMP/PKA pathway and ROS.

  16. Class IA phosphatidylinositol 3-kinase p110α regulates phagosome maturation.

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    Emily P Thi

    Full Text Available Of the various phosphatidylinositol 3- kinases (PI3Ks, only the class III enzyme Vps34 has been shown to regulate phagosome maturation. During studies of phagosome maturation in THP-1 cells deficient in class IA PI3K p110α, we discovered that this PI3K isoform is required for vacuole maturation to progress beyond acquisition of Rab7 leading to delivery of lysosomal markers. Bead phagosomes from THP-1 cells acquired p110α and contained PI3P and PI(3,4,5P3; however, p110α and PI(3,4,5P3 levels in phagosomes from p110α knockdown cells were decreased. Phagosomes from p110α knock down cells showed normal acquisition of both Rab5 and EEA-1, but were markedly deficient in the lysosomal markers LAMP-1 and LAMP-2, and the lysosomal hydrolase, β-galactosidase. Phagosomes from p110α deficient cells also displayed impaired fusion with Texas Red dextran-loaded lysosomes. Despite lacking lysosomal components, phagosomes from p110α deficient cells recruited normal levels of Rab7, Rab-interacting lysosomal protein (RILP and homotypic vacuole fusion and protein sorting (HOPs components Vps41 and Vps16. The latter observations demonstrated that phagosomal Rab7 was active and capable of recruiting effectors involved in membrane fusion. Nevertheless, active Rab7 was not sufficient to bring about the delivery of lysosomal proteins to the maturing vacuole, which is shown for the first time to be dependent on a class I PI3K.

  17. Aminoguanidine treatment increased NOX2 response in diabetic rats: Improved phagocytosis and killing of Candida albicans by neutrophils.

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    de Souza Ferreira, Cláudia; Pennacchi, Paula Commune; Araújo, Tomaz Henrique; Taniwaki, Noemi Nosomi; de Araújo Paula, Fernanda Borges; da Silveira Duarte, Stella Maris; Rodrigues, Maria Rita

    2016-02-05

    In this study, we show that aminoguanidine (AMG), an inhibitor of protein glycation, increases the NOX2 (phagocyte NADPH oxidase) response and microbicidal activity by neutrophils, regardless of diabetic status. The non-enzymatic glycation of proteins, yielding irreversible advanced glycation end products (AGEs), is involved in the development of diabetes complications, including alterations of signaling pathways and the generation of reactive oxygen species by phagocytes. The phagocytes produce ROS (reactive oxygen species) through activation of the NOX2 complex, which generates superoxide. The purpose of this study was to evaluate the effect of hyperglycemia and the glycation of proteins on the NOX2 activity of neutrophils and its implications for cellular physiology, with a focus on the microbicidal activity of these cells. We treated diabetic rats with AMG and evaluated neutrophil ROS generation and Candida albicans killing ability. We observed a large increase in the microbicidal activity of peritoneal neutrophils from AMG-treated rats. The increase was independent of diabetic status and myeloperoxidase activity. Collectively, our results suggest that AMG has an immunomodulator role that triggers an increase in the microbicidal response of neutrophils mainly related to reactive oxygen species production by NOX2.

  18. ROS-induced ROS release orchestrated by Nox4, Nox2, and mitochondria in VEGF signaling and angiogenesis.

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    Kim, Young-Mee; Kim, Seok-Jo; Tatsunami, Ryosuke; Yamamura, Hisao; Fukai, Tohru; Ushio-Fukai, Masuko

    2017-06-01

    Reactive oxygen species (ROS) derived from NADPH oxidase (NOX) and mitochondria play a critical role in growth factor-induced switch from a quiescent to an angiogenic phenotype in endothelial cells (ECs). However, how highly diffusible ROS produced from different sources can coordinate to stimulate VEGF signaling and drive the angiogenic process remains unknown. Using the cytosol- and mitochondria-targeted redox-sensitive RoGFP biosensors with real-time imaging, here we show that VEGF stimulation in human ECs rapidly increases cytosolic RoGFP oxidation within 1 min, followed by mitochondrial RoGFP oxidation within 5 min, which continues at least for 60 min. Silencing of Nox4 or Nox2 or overexpression of mitochondria-targeted catalase significantly inhibits VEGF-induced tyrosine phosphorylation of VEGF receptor type 2 (VEGFR2-pY), EC migration and proliferation at the similar extent. Exogenous hydrogen peroxide (H2O2) or overexpression of Nox4, which produces H2O2, increases mitochondrial ROS (mtROS), which is prevented by Nox2 siRNA, suggesting that Nox2 senses Nox4-derived H2O2 to promote mtROS production. Mechanistically, H2O2 increases S36 phosphorylation of p66Shc, a key mtROS regulator, which is inhibited by siNox2, but not by siNox4. Moreover, Nox2 or Nox4 knockdown or overexpression of S36 phosphorylation-defective mutant p66Shc(S36A) inhibits VEGF-induced mtROS, VEGFR2-pY, EC migration, and proliferation. In summary, Nox4-derived H2O2 in part activates Nox2 to increase mtROS via pSer36-p66Shc, thereby enhancing VEGFR2 signaling and angiogenesis in ECs. This may represent a novel feed-forward mechanism of ROS-induced ROS release orchestrated by the Nox4/Nox2/pSer36-p66Shc/mtROS axis, which drives sustained activation of angiogenesis signaling program. Copyright © 2017 the American Physiological Society.

  19. NADPH Oxidase Isoform 2 (NOX2 Is Involved in Drug Addiction Vulnerability in Progeny Developmentally Exposed to Ethanol

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    Marcela L. Contreras

    2017-06-01

    Full Text Available Ethanol exposure increases oxidative stress in developing organs, including the brain. Antioxidant treatment during maternal ethanol ingestion improves behavioral deficits in rodent models of fetal alcohol spectrum disorder (FASD. However, the impact of general antioxidant treatment in their adult offspring and the Specific Reactive Species (ROS-dependent mechanism, are not fully understood. We hypothesized that pre and early postnatal ethanol exposure (PEE modifies redox homeostasis, in particular NOX2 function during reward signaling in the mesocorticolimbic pathway, which reinforces the effects of alcohol. We developed a FASD rat model which was evaluated during adolescence (P21 and adulthood (P70. We first studied whether redox homeostasis is affected in PEE animals, by analyzing mRNA expression of SOD1, CAT, and Gpx1. We found that PEE reduced the mRNA levels of these three anti-oxidant enzymes in PFC and HIPP at P21 and in the VTA at P70. We also analyzed basal mRNA and protein expression of NOX2 subunits such as gp91phox, p22 phox, and p47 phox, in mesocorticolimbic brain areas of PEE rat brains. At P21, gp91 phox, and p47 phox levels in the VTA were decreased. At P70, gp91 phox mRNA levels was decreased in HIPP and both mRNA and protein levels were decreased in PFC. Since NOX2 is regulated by the N-methyl-D-aspartate Receptor (NMDAR, we analyzed NMDAR mRNA expression and found differential expression of NMDAR subunits (NR1 and NR2B in the PFC that was age dependent, with levels decreased at P21 and increased at P70. The analysis also revealed decreased NR2B mRNA expression in HIPP and VTA at P70. Offspring from maternal ethanol users consumed 25% more ethanol in a free choice alcohol consumption test than control rats, and showed place preference for an alcohol-paired compartment. In vivo inhibition of NOX2 using apocynin in drinking water, or infusion of blocked peptide gp91 phox ds in the VTA normalized alcohol place preference

  20. Phagosomes Induced by Cytokines Function as anti-Listeria Vaccines

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    Carrasco-Marín, Eugenio; Rodriguez-Del Rio, Estela; Frande-Cabanes, Elisabet; Tobes, Raquel; Pareja, Eduardo; Lecea-Cuello, M. Jesús; Ruiz-Sáez, Marta; Madrazo-Toca, Fidel; Hölscher, Christoph; Alvarez-Dominguez, Carmen

    2012-01-01

    Phagosomes are critical compartments for innate immunity. However, their role in the protection against murine listeriosis has not been examined. We describe here that listericidal phago-receptosomes are induced by the function of IFN-γ or IL-6 as centralized compartments for innate and adaptive immunity because they are able to confer protection against murine listeriosis. These phago-receptosomes elicited LLO(91–99)/CD8+- and LLO(189–201)/CD4+-specific immune responses and recruited mature dendritic cells to the vaccination sites controlled by T cells. Moreover, they present exceptional features as efficient vaccine vectors. First, they compartmentalize a novel listericidal STAT-1-mediated signaling pathway that confines multiple innate immune components to the same environment. Second, they show features of MHC class II antigen-loading competent compartments for cathepsin-D-mediated LLO processing. Third, murine cathepsin-D deficiencies fail to develop protective immunity after vaccination with listericidal phago-receptosomes induced by IFN-γ or IL-6. Therefore, it appears that the connection of STAT-1 and cathepsin-D in a single compartment is relevant for protection against listeriosis. PMID:22337873

  1. CLIC1 regulates dendritic cell antigen processing and presentation by modulating phagosome acidification and proteolysis

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    Kanin Salao

    2016-05-01

    Full Text Available Intracellular chloride channel protein 1 (CLIC1 participates in inflammatory processes by regulating macrophage phagosomal functions such as pH and proteolysis. Here, we sought to determine if CLIC1 can regulate adaptive immunity by actions on dendritic cells (DCs, the key professional antigen presenting cells. To do this, we first generated bone marrow-derived DCs (BMDCs from germline CLIC1 gene-deleted (CLIC1−/− and wild-type (CLIC1+/+ mice, then studied them in vitro and in vivo. We found phagocytosis triggered cytoplasmic CLIC1 translocation to the phagosomal membrane where it regulated phagosomal pH and proteolysis. Phagosomes from CLIC1−/− BMDCs displayed impaired acidification and proteolysis, which could be reproduced if CLIC1+/+, but not CLIC1−/− cells, were treated with IAA94, a CLIC family ion channel blocker. CLIC1−/− BMDC displayed reduced in vitro antigen processing and presentation of full-length myelin oligodendrocyte glycoprotein (MOG and reduced MOG-induced experimental autoimmune encephalomyelitis. These data suggest that CLIC1 regulates DC phagosomal pH to ensure optimal processing of antigen for presentation to antigen-specific T-cells. Further, they indicate that CLIC1 is a novel therapeutic target to help reduce the adaptive immune response in autoimmune diseases.

  2. Homocysteine-induced apoptosis in endothelial cells coincides with nuclear NOX2 and peri-nuclear NOX4 activity.

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    Sipkens, Jessica A; Hahn, Nynke; van den Brand, Carlien S; Meischl, Christof; Cillessen, Saskia A G M; Smith, Desirée E C; Juffermans, Lynda J M; Musters, René J P; Roos, Dirk; Jakobs, Cornelis; Blom, Henk J; Smulders, Yvo M; Krijnen, Paul A J; Stehouwer, Coen D A; Rauwerda, Jan A; van Hinsbergh, Victor W M; Niessen, Hans W M

    2013-11-01

    Apoptosis of endothelial cells related to homocysteine (Hcy) has been reported in several studies. In this study, we evaluated whether reactive oxygen species (ROS)-producing signaling pathways contribute to Hcy-induced apoptosis induction, with specific emphasis on NADPH oxidases. Human umbilical vein endothelial cells were incubated with 0.01-2.5 mM Hcy. We determined the effect of Hcy on caspase-3 activity, annexin V positivity, intracellular NOX1, NOX2, NOX4, and p47(phox) expression and localization, nuclear nitrotyrosine accumulation, and mitochondrial membrane potential (ΔΨ m). Hcy induced caspase-3 activity and apoptosis; this effect was concentration dependent and maximal after 6-h exposure to 2.5 mM Hcy. It was accompanied by a significant increase in ΔΨ m. Cysteine was inactive on these parameters excluding a reactive thiol group effect. Hcy induced an increase in cellular NOX2, p47(phox), and NOX4, but not that of NOX1. 3D digital imaging microscopy followed by image deconvolution analysis showed nuclear accumulation of NOX2 and p47(phox) in endothelial cells exposed to Hcy, but not in control cells, which coincided with accumulation of nuclear nitrotyrosine residues. Furthermore, Hcy enhanced peri-nuclear localization of NOX4 coinciding with accumulation of peri-nuclear nitrotyrosine residues, a reflection of local ROS production. p47(phox) was also increased in the peri-nuclear region. The Hcy-induced increase in caspase-3 activity was prevented by DPI and apocynin, suggesting involvement of NOX activity. The data presented in this article reveal accumulation of nuclear NOX2 and peri-nuclear NOX4 accumulation as potential source of ROS production in Hcy-induced apoptosis in endothelial cells.

  3. Blockage of NOX2/MAPK/NF-κB Pathway Protects Photoreceptors against Glucose Deprivation-Induced Cell Death

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    Bin Fan

    2017-01-01

    Full Text Available Acute energy failure is one of the critical factors contributing to the pathogenic mechanisms of retinal ischemia. Our previous study demonstrated that glucose deprivation can lead to a caspase-dependent cell death of photoreceptors. The aim of this study was to decipher the upstream signal pathway in glucose deprivation- (GD- induced cell death. We mimicked acute energy failure by using glucose deprivation in photoreceptor cells (661W cells. GD-induced oxidative stress was evaluated by measuring ROS with the DCFH-DA assay and HO-1 expression by Western blot analysis. The activation of NOX2/MAPK/NF-κB signal was assessed by Western blot and immunohistochemical assays. The roles of these signals in GD-induced cell death were measured by using their specific inhibitors. Inhibition of Rac-1 and NOX2 suppressed GD-induced oxidative stress and protected photoreceptors against GD-induced cell death. NOX2 was an upstream signal in the caspase-dependent cell death cascade, yet the downstream MAPK pathways were activated and blocking MAPK signals rescued 661W cells from GD-induced death. In addition, GD caused the activation of NF-κB signal and inhibiting NF-κB significantly protected 661W cells. These observations may provide insights for treating retinal ischemic diseases and protecting retinal neurons from ischemia-induced cell death.

  4. Nox-2-mediated phenotype loss of hippocampal parvalbumin interneurons might contribute to postoperative cognitive decline in aging mice

    Directory of Open Access Journals (Sweden)

    lili qiu

    2016-10-01

    Full Text Available Postoperative cognitive decline (POCD is a common complication following anesthesia and surgery, especially in elderly patients; however, the precise mechanisms of POCD remain unclear. Here, we investigated whether nicotinamide adenine dinucleotide phosphate (NADPH oxidase mediated-abnormalities in parvalbumin (PV interneurons play an important role in the pathophysiology of POCD. The animal model was established using isoflurane anesthesia and exploratory laparotomy in sixteen-month-old male C57BL/6 mice. For interventional experiments, mice were chronically treated with the NADPH oxidase inhibitor apocynin (APO. Open field and fear conditioning behavioral tests were performed on day 6 and 7 post-surgery, respectively. In a separate experiment, brain tissue was harvested and subjected to biochemical analysis. Primary hippocampal neurons challenged with lipopolysaccharide in vitro were used to investigate the mechanisms underlying the oxidative stress-induced abnormalities in PV interneurons. Our results showed that anesthesia and surgery induced significant hippocampus-dependent memory impairment, which was accompanied by PV interneuron phenotype loss and increased expression of interleukin-1β, markers of oxidative stress, and NADPH oxidase 2 (Nox2 in the hippocampus. In addition, lipopolysaccharide exposure increased Nox2 level and decreased the expression of PV and the number of excitatory synapses onto PV interneurons in the primary hippocampal neurons. Notably, treatment with APO reversed these abnormalities. Our study suggests that Nox2-derived ROS production triggers, at least in part, anesthesia- and surgery-induced hippocampal PV interneuron phenotype loss and consequent cognitive impairment in aging mice.

  5. The Mycobacterium tuberculosis phagosome is a HLA-I processing competent organelle.

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    Jeff E Grotzke

    2009-04-01

    Full Text Available Mycobacterium tuberculosis (Mtb resides in a long-lived phagosomal compartment that resists maturation. The manner by which Mtb antigens are processed and presented on MHC Class I molecules is poorly understood. Using human dendritic cells and IFN-gamma release by CD8(+ T cell clones, we examined the processing and presentation pathway for two Mtb-derived antigens, each presented by a distinct HLA-I allele (HLA-Ia versus HLA-Ib. Presentation of both antigens is blocked by the retrotranslocation inhibitor exotoxin A. Inhibitor studies demonstrate that, after reaching the cytosol, both antigens require proteasomal degradation and TAP transport, but differ in the requirement for ER-golgi egress and new protein synthesis. Specifically, presentation by HLA-B8 but not HLA-E requires newly synthesized HLA-I and transport through the ER-golgi. Phenotypic analysis of the Mtb phagosome by flow organellometry revealed the presence of Class I and loading accessory molecules, including TAP and PDI. Furthermore, loaded HLA-I:peptide complexes are present within the Mtb phagosome, with a pronounced bias towards HLA-E:peptide complexes. In addition, protein analysis also reveals that HLA-E is enriched within the Mtb phagosome compared to HLA-A2. Together, these data suggest that the phagosome, through acquisition of ER-localized machinery and as a site of HLA-I loading, plays a vital role in the presentation of Mtb-derived antigens, similar to that described for presentation of latex bead-associated antigens. This is, to our knowledge, the first description of this presentation pathway for an intracellular pathogen. Moreover, these data suggest that HLA-E may play a unique role in the presentation of phagosomal antigens.

  6. Cytosolic access of Mycobacterium tuberculosis: critical impact of phagosomal acidification control and demonstration of occurrence in vivo.

    Directory of Open Access Journals (Sweden)

    Roxane Simeone

    2015-02-01

    Full Text Available Mycobacterium tuberculosis (Mtb uses efficient strategies to evade the eradication by professional phagocytes, involving--as recently confirmed--escape from phagosomal confinement. While Mtb determinants, such as the ESX-1 type VII secretion system, that contribute to this phenomenon are known, the host cell factors governing this important biological process are yet unexplored. Using a newly developed flow-cytometric approach for Mtb, we show that macrophages expressing the phagosomal bivalent cation transporter Nramp-1, are much less susceptible to phagosomal rupture. Together with results from the use of the phagosome acidification inhibitor bafilomycin, we demonstrate that restriction of phagosomal acidification is a prerequisite for mycobacterial phagosomal rupture and cytosolic contact. Using different in vivo approaches including an enrichment and screen for tracking rare infected phagocytes carrying the CD45.1 hematopoietic allelic marker, we here provide first and unique evidence of M. tuberculosis-mediated phagosomal rupture in mouse spleen and lungs and in numerous phagocyte types. Our results, linking the ability of restriction of phagosome acidification to cytosolic access, provide an important conceptual advance for our knowledge on host processes targeted by Mtb evasion strategies.

  7. Role of the Brucella suis Lipopolysaccharide O Antigen in Phagosomal Genesis and in Inhibition of Phagosome-Lysosome Fusion in Murine Macrophages

    Science.gov (United States)

    Porte, Françoise; Naroeni, Aroem; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre

    2003-01-01

    Brucella species are gram-negative, facultative intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment inside professional and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both cell types. However, the molecular mechanisms and the microbial factors involved are poorly understood. Smooth lipopolysaccharide (LPS) of Brucella has been reported to be an important virulence factor, although its precise role in pathogenesis is not yet clear. In this study, we show that the LPS O side chain is involved in inhibition of the early fusion between Brucella suis-containing phagosomes and lysosomes in murine macrophages. In contrast, the phagosomes containing rough mutants, which fail to express the O antigen, rapidly fuse with lysosomes. In addition, we show that rough mutants do not enter host cells by using lipid rafts, contrary to smooth strains. Thus, we propose that the LPS O chain might be a major factor that governs the early behavior of bacteria inside macrophages. PMID:12595466

  8. Nox2-dependent glutathionylation of endothelial NOS leads to uncoupled superoxide production and endothelial barrier dysfunction in acute lung injury.

    Science.gov (United States)

    Wu, Feng; Szczepaniak, William S; Shiva, Sruti; Liu, Huanbo; Wang, Yinna; Wang, Ling; Wang, Ying; Kelley, Eric E; Chen, Alex F; Gladwin, Mark T; McVerry, Bryan J

    2014-12-15

    Microvascular barrier integrity is dependent on bioavailable nitric oxide (NO) produced locally by endothelial NO synthase (eNOS). Under conditions of limited substrate or cofactor availability or by enzymatic modification, eNOS may become uncoupled, producing superoxide in lieu of NO. This study was designed to investigate how eNOS-dependent superoxide production contributes to endothelial barrier dysfunction in inflammatory lung injury and its regulation. C57BL/6J mice were challenged with intratracheal LPS. Bronchoalveolar lavage fluid was analyzed for protein accumulation, and lung tissue homogenate was assayed for endothelial NOS content and function. Human lung microvascular endothelial cell (HLMVEC) monolayers were exposed to LPS in vitro, and barrier integrity and superoxide production were measured. Biopterin species were quantified, and coimmunoprecipitation (Co-IP) assays were performed to identify protein interactions with eNOS that putatively drive uncoupling. Mice exposed to LPS demonstrated eNOS-dependent increased alveolar permeability without evidence for altered canonical NO signaling. LPS-induced superoxide production and permeability in HLMVEC were inhibited by the NOS inhibitor nitro-l-arginine methyl ester, eNOS-targeted siRNA, the eNOS cofactor tetrahydrobiopterin, and superoxide dismutase. Co-IP indicated that LPS stimulated the association of eNOS with NADPH oxidase 2 (Nox2), which correlated with augmented eNOS S-glutathionylation both in vitro and in vivo. In vitro, Nox2-specific inhibition prevented LPS-induced eNOS modification and increases in both superoxide production and permeability. These data indicate that eNOS uncoupling contributes to superoxide production and barrier dysfunction in the lung microvasculature after exposure to LPS. Furthermore, the results implicate Nox2-mediated eNOS-S-glutathionylation as a mechanism underlying LPS-induced eNOS uncoupling in the lung microvasculature.

  9. Geraniol improves endothelial function by inhibiting NOX-2 derived oxidative stress in high fat diet fed mice

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoyu; Zhao, Shiqi; Su, Mengqi; Sun, Li; Zhang, Song; Wang, Dingyu; Liu, Zhaorui; Yuan, Yue; Liu, Yang [Department of Cardiology, the First Affiliated Hospital, Harbin Medical University, Harbin 150001, Heilongjiang Province (China); Li, Yue, E-mail: ly99ly@vip.163.com [Department of Cardiology, the First Affiliated Hospital, Harbin Medical University, Harbin 150001, Heilongjiang Province (China); Key Laboratory of Cardiac Diseases and Heart Failure, Harbin Medical University, Harbin, 150001, Heilongjiang Province (China)

    2016-05-20

    Endothelial dysfunction occurs in obese patients and high-fat diet (HFD) fed experimental animals. While geraniol has been reported to ameliorate inflammation and oxidative stress, inhibit tumor cell proliferation, and improve atherosclerosis, its direct effect on endothelial function remains uncharacterized. The present study therefore investigated the effect of geraniol on endothelial function in HFD mice and its underlying mechanisms. C57 BL/6 mice were fed an HFD (n = 40) or a normal diet (n = 20) for 8 weeks. HFD fed mice then were randomized to intraperitoneal treatment with geraniol (n = 20) or vehicle (n = 20) for another 6 weeks. Acetylcholine (Ach)-induced endothelial dependent vasorelaxation was measured on wire myography; reactive oxygen species (ROS) generation was assessed by fluorescence imaging, and NADPH oxidases (NOXs) and adhesive molecules VCAM-1 and ICAM-1 protein expression by western blotting. Geraniol improved endothelial function in HFD fed mice, as evidenced by its: 1. restoring endothelial dependent vasorelaxation induced by Ach, and reversing increased VCAM-1 and ICAM-1 expression; 2. attenuating HFD induced increased serum TBARS and aortic ROS generation; and 3. downregulating aortic NOX-2 expression in both HFD fed mice and in palmitic acid treated endothelial cells. Geraniol therefore protects against endothelial dysfunction induced by HFD through reducing NOX-2 associated ROS generation. -- Highlights: •Geraniol improved endothelial dependent relaxation in high fat diet fed mice. •Geraniol alleviated vascular injury in high fat diet fed mice. •Geraniol inhibited ROS generation through downregulating NOX-2 expression.

  10. Ofloxacin induces apoptosis via β1 integrin-EGFR-Rac1-Nox2 pathway in microencapsulated chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Zhi-Guo [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Huang, Wei [Department of Chemical Biology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 1000191 (China); Liu, Yu-Xiang [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Yuan, Ye [Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850 (China); Zhu, Ben-Zhan, E-mail: bzhu@rcees.ac.cn [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Linus Pauling Institute, Oregon State University, Corvallis, OR 97331 (United States)

    2013-02-15

    Quinolones (QNs)-induced arthropathy is an important toxic side-effect in immature animals leading to the restriction of their therapeutic use in pediatrics. Ofloxacin, a typical QN, was found to induce the chondrocytes apoptosis in the early phase (12–48 h) of arthropathy in our previous study. However, the exact mechanism(s) is unclear. Microencapsulated juvenile rabbit joint chondrocytes, a three-dimensional culture system, is utilized to perform the present study. Ofloxacin, at a therapeutically relevant concentration (10 μg/ml), disturbs the interaction between β1 integrin and activated intracellular signaling proteins at 12 h, which is inhibited when supplementing Mg{sup 2+}. Intracellular reactive oxygen species (ROS) significantly increases in a time-dependent manner after exposure to ofloxacin for 12–48 h. Furthermore, ofloxacin markedly enhances the level of activated Rac1 and epidermal growth factor receptor (EGFR) phosphorylation, and its inhibition in turn reduces the ROS production, apoptosis and Rac1 activation. Silencing Nox2, Rac1 or supplementing Mg{sup 2+} inhibits ROS accumulation, apoptosis occurrence and EGFR phosphorylation induced by ofloxacin. However, depletion of Nox2, Rac1 and inhibition of EGFR do not affect ofloxacin-mediated loss of interaction between β1 integrin and activated intracellular signaling proteins. In addition, ofloxacin also induces Vav2 phosphorylation, which is markedly suppressed after inactivating EGFR or supplementing Mg{sup 2+}. These results suggest that ofloxacin causes Nox2-mediated intracellular ROS production by disrupting the β1 integrin function and then activating the EGFR-Vav2-Rac1 pathway, finally resulting in apoptosis within 12–48 h exposure. The present study provides a novel insight regarding the potential role of Nox-driven ROS in QNs-induced arthropathy. - Highlights: ► Ofloxacin induces Nox2-driven ROS in encapsulated chondrocyte at 12–48 h. ► Ofloxacin stimulates ROS production via

  11. Retrieval of the vacuolar H-ATPase from phagosomes revealed by live cell imaging.

    Directory of Open Access Journals (Sweden)

    Margaret Clarke

    Full Text Available BACKGROUND: The vacuolar H+-ATPase, or V-ATPase, is a highly-conserved multi-subunit enzyme that transports protons across membranes at the expense of ATP. The resulting proton gradient serves many essential functions, among them energizing transport of small molecules such as neurotransmitters, and acidifying organelles such as endosomes. The enzyme is not present in the plasma membrane from which a phagosome is formed, but is rapidly delivered by fusion with endosomes that already bear the V-ATPase in their membranes. Similarly, the enzyme is thought to be retrieved from phagosome membranes prior to exocytosis of indigestible material, although that process has not been directly visualized. METHODOLOGY: To monitor trafficking of the V-ATPase in the phagocytic pathway of Dictyostelium discoideum, we fed the cells yeast, large particles that maintain their shape during trafficking. To track pH changes, we conjugated the yeast with fluorescein isothiocyanate. Cells were labeled with VatM-GFP, a fluorescently-tagged transmembrane subunit of the V-ATPase, in parallel with stage-specific endosomal markers or in combination with mRFP-tagged cytoskeletal proteins. PRINCIPAL FINDINGS: We find that the V-ATPase is commonly retrieved from the phagosome membrane by vesiculation shortly before exocytosis. However, if the cells are kept in confined spaces, a bulky phagosome may be exocytosed prematurely. In this event, a large V-ATPase-rich vacuole coated with actin typically separates from the acidic phagosome shortly before exocytosis. This vacuole is propelled by an actin tail and soon acquires the properties of an early endosome, revealing an unexpected mechanism for rapid recycling of the V-ATPase. Any V-ATPase that reaches the plasma membrane is also promptly retrieved. CONCLUSIONS/SIGNIFICANCE: Thus, live cell microscopy has revealed both a usual route and alternative means of recycling the V-ATPase in the endocytic pathway.

  12. The Leishmania donovani lipophosphoglycan excludes the vesicular proton-ATPase from phagosomes by impairing the recruitment of synaptotagmin V.

    Directory of Open Access Journals (Sweden)

    Adrien F Vinet

    2009-10-01

    Full Text Available We recently showed that the exocytosis regulator Synaptotagmin (Syt V is recruited to the nascent phagosome and remains associated throughout the maturation process. In this study, we investigated the possibility that Syt V plays a role in regulating interactions between the phagosome and the endocytic organelles. Silencing of Syt V by RNA interference revealed that Syt V contributes to phagolysosome biogenesis by regulating the acquisition of cathepsin D and the vesicular proton-ATPase. In contrast, recruitment of cathepsin B, the early endosomal marker EEA1 and the lysosomal marker LAMP1 to phagosomes was normal in the absence of Syt V. As Leishmania donovani promastigotes inhibit phagosome maturation, we investigated their potential impact on the phagosomal association of Syt V. This inhibition of phagolysosome biogenesis is mediated by the virulence glycolipid lipophosphoglycan, a polymer of the repeating Galbeta1,4Manalpha1-PO(4 units attached to the promastigote surface via an unusual glycosylphosphatidylinositol anchor. Our results showed that insertion of lipophosphoglycan into ganglioside GM1-containing microdomains excluded or caused dissociation of Syt V from phagosome membranes. As a consequence, L. donovani promatigotes established infection in a phagosome from which the vesicular proton-ATPase was excluded and which failed to acidify. Collectively, these results reveal a novel function for Syt V in phagolysosome biogenesis and provide novel insight into the mechanism of vesicular proton-ATPase recruitment to maturing phagosomes. We also provide novel findings into the mechanism of Leishmania pathogenesis, whereby targeting of Syt V is part of the strategy used by L. donovani promastigotes to prevent phagosome acidification.

  13. Two PI 3-kinases and one PI 3-phosphatase together establish the cyclic waves of phagosomal PtdIns(3P critical for the degradation of apoptotic cells.

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2012-01-01

    Full Text Available Phosphatidylinositol 3-phosphate (PtdIns(3P is a signaling molecule important for many membrane trafficking events, including phagosome maturation. The level of PtdIns(3P on phagosomes oscillates in two waves during phagosome maturation. However, the physiological significance of such oscillation remains unknown. Currently, the Class III PI 3-kinase (PI3K Vps34 is regarded as the only kinase that produces PtdIns(3P in phagosomal membranes. We report here that, in the nematode C. elegans, the Class II PI3K PIKI-1 plays a novel and crucial role in producing phagosomal PtdIns(3P. PIKI-1 is recruited to extending pseudopods and nascent phagosomes prior to the appearance of PtdIns(3P in a manner dependent on the large GTPase dynamin (DYN-1. PIKI-1 and VPS-34 act in sequence to provide overlapping pools of PtdIns(3P on phagosomes. Inactivating both piki-1 and vps-34 completely abolishes the production of phagosomal PtdIns(3P and disables phagosomes from recruiting multiple essential maturation factors, resulting in a complete arrest of apoptotic-cell degradation. We have further identified MTM-1, a PI 3-phosphatase that antagonizes the activities of PIKI-1 and VPS-34 by down-regulating PtdIns(3P on phagosomes. Remarkably, persistent appearance of phagosomal PtdIns(3P, as a result of inactivating mtm-1, blocks phagosome maturation. Our findings demonstrate that the proper oscillation pattern of PtdIns(3P on phagosomes, programmed by the coordinated activities of two PI3Ks and one PI 3-phosphatase, is critical for phagosome maturation. They further shed light on how the temporally controlled reversible phosphorylation of phosphoinositides regulates the progression of multi-step cellular events.

  14. Molecular Mechanisms of Curcumin on Diabetes-Induced Endothelial Dysfunctions: Txnip, ICAM-1, and NOX2 Expressions

    Directory of Open Access Journals (Sweden)

    Natchaya Wongeakin

    2014-01-01

    Full Text Available We aim to investigate the effects of curcumin on preventing diabetes-induced vascular inflammation in association with its actions on Txnip, ICAM-1, and NOX2 enzyme expressions. Male Wistar rats were divided into four groups: control (CON, diabetic (DM; streptozotocin (STZ, i.v. 55 mg/kg BW, control-treated with curcumin (CONCUR; 300 mg/kg BW, and diabetes treated with curcumin (DMCUR; 300 mg/kg BW. 12th week after STZ injection, iris blood perfusion, leukocyte adhesion, Txnip, p47phox, and malondialdehyde (MDA levels were determined by using laser Doppler, intravital fluorescent confocal microscopy, Western Blot analysis, and TBAR assay, respectively. The iris blood perfusion of DM and DMCUR was decreased significantly compared to CON and CONCUR (P<0.001. Plasma glucose and HbA1c of DM and DMCUR were increased significantly compared to CON and CONCUR (P<0.001. Leukocyte adhesion, ICAM-1, p47phox expression, and MDA levels in DM were increased significantly compared to CON, CONCUR, and DMCUR (P<0.05. Txnip expression in DM and DMCUR was significantly higher than CON and CONCUR (P<0.05. From Pearson’s analysis, the correlation between the plasma MDA level and the endothelial functions was significant. It suggested that curcumin could ameliorate diabetic vascular inflammation by decreasing ROS overproduction, reducing leukocyte-endothelium interaction, and inhibiting ICAM-1 and NOX2 expression.

  15. Distributed performance counters

    Science.gov (United States)

    Davis, Kristan D; Evans, Kahn C; Gara, Alan; Satterfield, David L

    2013-11-26

    A plurality of first performance counter modules is coupled to a plurality of processing cores. The plurality of first performance counter modules is operable to collect performance data associated with the plurality of processing cores respectively. A plurality of second performance counter modules are coupled to a plurality of L2 cache units, and the plurality of second performance counter modules are operable to collect performance data associated with the plurality of L2 cache units respectively. A central performance counter module may be operable to coordinate counter data from the plurality of first performance counter modules and the plurality of second performance modules, the a central performance counter module, the plurality of first performance counter modules, and the plurality of second performance counter modules connected by a daisy chain connection.

  16. TAP mediates import of Mycobacterium tuberculosis-derived peptides into phagosomes and facilitates loading onto HLA-I.

    Directory of Open Access Journals (Sweden)

    Melanie J Harriff

    Full Text Available Processing and presentation of antigen on MHC-I class I molecules serves to present peptides derived from cytosolic proteins to CD8(+ T cells. Infection with bacteria that remain in phagosomal compartments, such as Mycobacterium tuberculosis (Mtb, provides a challenge to this immune recognition as bacterial proteins are segregated from the cytosol. Previously we identified the Mtb phagosome itself as an organelle capable of loading MHC Class I molecules with Mtb antigens. Here, we find that the TAP transporter, responsible for importing peptides into the ER for loading in Class I molecules, is both present and functional in Mtb phagosomes. Furthermore, we describe a novel peptide reagent, representing the N-terminal domain of the bovine herpes virus UL49.5 protein, which is capable of specifically inhibiting the lumenal face of TAP. Together, these results provide insight into the mechanism by which peptides from intra-phagosomal pathogens are loaded onto Class I molecules.

  17. Bacterial ligands generated in a phagosome are targets of the cytosolic innate immune system.

    Directory of Open Access Journals (Sweden)

    Anat A Herskovits

    2007-03-01

    Full Text Available Macrophages are permissive hosts to intracellular pathogens, but upon activation become microbiocidal effectors of innate and cell-mediated immunity. How the fate of internalized microorganisms is monitored by macrophages, and how that information is integrated to stimulate specific immune responses is not understood. Activation of macrophages with interferon (IFN-gamma leads to rapid killing and degradation of Listeria monocytogenes in a phagosome, thus preventing escape of bacteria to the cytosol. Here, we show that activated macrophages induce a specific gene expression program to L. monocytogenes degraded in the phago-lysosome. In addition to activation of Toll-like receptor (TLR signaling pathways, degraded bacteria also activated a TLR-independent transcriptional response that was similar to the response induced by cytosolic L. monocytogenes. More specifically, degraded bacteria induced a TLR-independent IFN-beta response that was previously shown to be specific to cytosolic bacteria and not to intact bacteria localized to the phagosome. This response required the generation of bacterial ligands in the phago-lysosome and was largely dependent on nucleotide-binding oligomerization domain 2 (NOD2, a cytosolic receptor known to respond to bacterial peptidoglycan fragments. The NOD2-dependent response to degraded bacteria required the phagosomal membrane potential and the activity of lysosomal proteases. The NOD2-dependent IFN-beta production resulted from synergism with other cytosolic microbial sensors. This study supports the hypothesis that in activated macrophages, cytosolic innate immune receptors are activated by bacterial ligands generated in the phagosome and transported to the cytosol.

  18. Curcumin inhibits the invasion of lung cancer cells by modulating the PKCα/Nox-2/ROS/ATF-2/MMP-9 signaling pathway.

    Science.gov (United States)

    Fan, Zhigang; Duan, Xiaoyi; Cai, Hui; Wang, Li; Li, Min; Qu, Jingkun; Li, Wanjun; Wang, Yongheng; Wang, Jiansheng

    2015-08-01

    Invasion and metastasis are the major causes of tumor-related mortality in lung cancer. It is believed that curcumin is an effective drug possessing anti-invasive and anti-metastatic activities in the treatment of cancer. However, the specific mechanisms remain unclear. In the present study, we investigated whether the PKCα/Nox-2/ATF-2/MMP-9 signaling pathway is involved in the invasive behavior of lung cancer and whether curcumin could inhibit invasion by modulating this pathway. The cytotoxic effect of curcumin was evaluated by MTT assay and the capacity of invasion was assessed by Transwell assay. siRNA and plasmid transfection techniques were used to study the function of targeted genes. Real-time PCR and western blot analysis were used to evaluate the expression levels of PKCα, Nox-2, MMP-9 and the phosphorylation of ATF-2. The results showed that curcumin inhibited the proliferation and invasion of A549 cells in a dose-dependent manner. Overexpression of MMP-9 enhanced the invasion of A549 cells. However, inhibition of MMP-9 by siRNA or curcumin suppressed cell invasion. Moreover, we also demonstrated the catalytic role of PKCα in expression of MMP-9 and cellular invasion in A549 cells, which was dependent on the expression of Nox-2 and phosphorylation of ATF-2. Finally, we also showed that curcumin dose-dependently reduced the expression of PKCα, P47phox, Nox-2 and phosphorylated ATF-2, as well as intracellular ROS generation, suggesting the inhibitory effect of curcumin on the activation of the PKCα/Nox-2/ROS/ATF-2 pathway. In conclusion, the PKCα/Nox-2/ROS/ATF-2/MMP-9 signaling pathway is activated in lung cancer A549 cells, which could be modulated by curcumin to inhibit cell invasiveness.

  19. Decoupling internalization, acidification and phagosomal-endosomal/lysosomal fusion during phagocytosis of InlA coated beads in epithelial cells.

    Directory of Open Access Journals (Sweden)

    Craig D Blanchette

    Full Text Available BACKGROUND: Phagocytosis has been extensively examined in 'professional' phagocytic cells using pH sensitive dyes. However, in many of the previous studies, a separation between the end of internalization, beginning of acidification and completion of phagosomal-endosomal/lysosomal fusion was not clearly established. In addition, very little work has been done to systematically examine phagosomal maturation in 'non-professional' phagocytic cells. Therefore, in this study, we developed a simple method to measure and decouple particle internalization, phagosomal acidification and phagosomal-endosomal/lysosomal fusion in Madin-Darby Canine Kidney (MDCK and Caco-2 epithelial cells. METHODOLOGY/PRINCIPAL FINDINGS: Our method was developed using a pathogen mimetic system consisting of polystyrene beads coated with Internalin A (InlA, a membrane surface protein from Listeria monocytogenes known to trigger receptor-mediated phagocytosis. We were able to independently measure the rates of internalization, phagosomal acidification and phagosomal-endosomal/lysosomal fusion in epithelial cells by combining the InlA-coated beads (InlA-beads with antibody quenching, a pH sensitive dye and an endosomal/lysosomal dye. By performing these independent measurements under identical experimental conditions, we were able to decouple the three processes and establish time scales for each. In a separate set of experiments, we exploited the phagosomal acidification process to demonstrate an additional, real-time method for tracking bead binding, internalization and phagosomal acidification. CONCLUSIONS/SIGNIFICANCE: Using this method, we found that the time scales for internalization, phagosomal acidification and phagosomal-endosomal/lysosomal fusion ranged from 23-32 min, 3-4 min and 74-120 min, respectively, for MDCK and Caco-2 epithelial cells. Both the static and real-time methods developed here are expected to be readily and broadly applicable, as they simply

  20. Counter-cryptanalysis

    NARCIS (Netherlands)

    Stevens, M.M.J.; Canetti, R.; Garay, J.A.

    2013-01-01

    We introduce \\emph{counter-cryptanalysis} as a new paradigm for strengthening weak cryptographic primitives against cryptanalytic attacks. Redesigning a weak primitive to more strongly resist cryptanalytic techniques will unavoidably break backwards compatibility. Instead, counter-cryptanalysis expl

  1. CEDAR counter (internal part)

    CERN Multimedia

    1976-01-01

    Here on the mounting bench. The counter is a differential Cerenkov, corrected for chromaticity, able to differentiate pions from kaons up to 350 GeV. Counters of this type were used in all SPS hadron beams.

  2. Real-time imaging of Leishmania mexicana-infected early phagosomes: a study using primary macrophages generated from green fluorescent protein-Rab5 transgenic mice

    OpenAIRE

    Lippuner, Christoph; Paape, Daniel; Paterou, Athina; Brand, Janko; Richardson, Melville; Smith, Andrew; Hoffmann, Kirstin; Brinkmann, Volker; Blackburn, Clare; Aebischer, Toni

    2009-01-01

    The small GTPase Rab5 is a key regulator of endosome/phagosome maturation and in intravesicular infections marks a phagosome stage at which decisions over pathogen replication or destruction are integrated. It is currently unclear whether Leishmania-infected phagosomes uniformly pass through a Rab5(+) stage on their intracellular path to compartments with late endosomal/early lysosomal characteristics. Differences in routes and final compartments could have consequences for accessibility to a...

  3. Real-time imaging of Leishmania mexicana-infected early phagosomes: a study using primary macrophages generated from green fluorescent protein-Rab5 transgenic mice

    OpenAIRE

    Lippuner, Christoph; Paape, Daniel; Paterou, Athina; Brand, Janko; Richardson, Melville; Smith, Andrew; Hoffmann, Kirstin; Brinkmann, Volker; Blackburn, Clare; Aebischer, Toni

    2009-01-01

    The small GTPase Rab5 is a key regulator of endosome/phagosome maturation and in intravesicular infections marks a phagosome stage at which decisions over pathogen replication or destruction are integrated. It is currently unclear whether Leishmania-infected phagosomes uniformly pass through a Rab5(+) stage on their intracellular path to compartments with late endosomal/early lysosomal characteristics. Differences in routes and final compartments could have consequences for accessibility to a...

  4. NOX2 Mediated-Parvalbumin Interneuron Loss Might Contribute to Anxiety-Like and Enhanced Fear Learning Behavior in a Rat Model of Post-Traumatic Stress Disorder.

    Science.gov (United States)

    Liu, Fang-Fang; Yang, Lin-Dong; Sun, Xiao-Ru; Zhang, Hui; Pan, Wei; Wang, Xing-Ming; Yang, Jian-Jun; Ji, Mu-Huo; Yuan, Hong-Mei

    2016-12-01

    Post-traumatic stress disorder (PTSD) is a common psychiatric disease following exposure to a severe traumatic event or physiological stress, yet the precise mechanisms underlying PTSD remains largely to be determined. Using an animal model of PTSD induced by a single prolonged stress (SPS), we assessed the role of hippocampal nicotinamide adenosine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) and parvalbumin (PV) interneurons in the development of PTSD symptoms. In the present study, behavioral tests were performed by the open field (day 13 after SPS) and fear conditioning tests (days 13 and 14 after SPS). For the interventional study, rats were chronically treated with a NADPH oxidase inhibitor apocynin either by early or delayed administration. The levels of tumor necrosis factor-alpha, interleukin (IL)-1β, IL-6, IL-10, malondialdehyde, superoxide dismutase, NOX2, 4-hydroxynonenal, and PV in the hippocampus were measured at the indicated time points. In the present study, we showed that SPS rats displayed anxiety-like and enhanced fear learning behavior, which was accompanied by the increased expressions of malondialdehyde, IL-6, NOX2, 4-hydroxynonenal, and decreased PV expression. Notably, early but not delayed treatment with apocynin reversed all these abnormalities after SPS. In conclusion, our results provided evidence that NOX2 activation in the hippocampus, at least in part, contributes to oxidative stress and neuroinflammation, which further results in PV interneuron loss and consequent PTSD symptoms in a rat model of PTSD induced by SPS.

  5. The dehydrogenase region of the NADPH oxidase component Nox2 acts as a protein disulfide isomerase (PDI) resembling PDIA3 with a role in the binding of the activator protein p67phox

    Science.gov (United States)

    Bechor, Edna; Dahan, Iris; Fradin, Tanya; Berdichevsky, Yevgeny; Zahavi, Anat; Rafalowski, Meirav; Federman-Gross, Aya; Pick, Edgar

    2015-02-01

    The superoxide (O2.-)-generating NADPH oxidase of phagocytes consists of a membrane component, cytochrome b558 (a heterodimer of Nox2 and p22phox), and four cytosolic components, p47phox, p67phox, p40phox, and Rac. The catalytic component, responsible for O2.- generation, is Nox2. It is activated by the interaction of the dehydrogenase region (DHR) of Nox2 with the cytosolic components, principally with p67phox. Using a peptide-protein binding assay, we found that Nox2 peptides containing a 369CysGlyCys371 triad (CGC) bound p67phox with high affinity, dependent upon the establishment of a disulfide bond between the two cysteines. Serially truncated recombinant Nox2 DHR proteins bound p67phox only when they comprised the CGC triad. CGC resembles the catalytic motif (CGHC) of protein disulfide isomerases (PDIs). This led to the hypothesis that Nox2 establishes disulfide bonds with p67phox via a thiol-dilsulfide exchange reaction and, thus, functions as a PDI. Evidence for this was provided by the following: 1. Recombinant Nox2 protein, which contained the CGC triad, exhibited PDI-like disulfide reductase activity; 2. Truncation of Nox2 C-terminal to the CGC triad or mutating C369 and C371 to R, resulted in loss of PDI activity; 3. Comparison of the sequence of the DHR of Nox2 with PDI family members revealed three small regions of homology with PDIA3; 4. Two monoclonal anti-Nox2 antibodies, with epitopes corresponding to regions of Nox2/PDIA3 homology, reacted with PDIA3 but not with PDIA1; 5. A polyclonal anti-PDIA3 (but not an anti-PDIA1) antibody reacted with Nox2; 6. p67phox, in which all cysteines were mutated to serines, lost its ability to bind to a Nox2 peptide containing the CGC triad and had an impaired capacity to support oxidase activity in vitro. We propose a model of oxidase assembly in which binding of p67phox to Nox2 via disulfide bonds, by virtue of the intrinsic PDI activity of Nox2, stabilizes the primary interaction between the two components.

  6. The dehydrogenase region of the NADPH oxidase component Nox2 acts as a protein disulfide isomerase (PDI) resembling PDIA3 with a role in the binding of the activator protein p67 (phox.).

    Science.gov (United States)

    Bechor, Edna; Dahan, Iris; Fradin, Tanya; Berdichevsky, Yevgeny; Zahavi, Anat; Federman Gross, Aya; Rafalowski, Meirav; Pick, Edgar

    2015-01-01

    The superoxide (O(·-) 2)-generating NADPH oxidase of phagocytes consists of a membrane component, cytochrome b 558 (a heterodimer of Nox2 and p22 (phox) ), and four cytosolic components, p47 (phox) , p67 (phox) , p40 (phox) , and Rac. The catalytic component, responsible for O(·-) 2 generation, is Nox2. It is activated by the interaction of the dehydrogenase region (DHR) of Nox2 with the cytosolic components, principally with p67 (phox) . Using a peptide-protein binding assay, we found that Nox2 peptides containing a (369)CysGlyCys(371) triad (CGC) bound p67 (phox) with high affinity, dependent upon the establishment of a disulfide bond between the two cysteines. Serially truncated recombinant Nox2 DHR proteins bound p67 (phox) only when they comprised the CGC triad. CGC resembles the catalytic motif (CGHC) of protein disulfide isomerases (PDIs). This led to the hypothesis that Nox2 establishes disulfide bonds with p67 (phox) via a thiol-dilsulfide exchange reaction and, thus, functions as a PDI. Evidence for this was provided by the following: (1) Recombinant Nox2 protein, which contained the CGC triad, exhibited PDI-like disulfide reductase activity; (2) Truncation of Nox2 C-terminal to the CGC triad or mutating C369 and C371 to R, resulted in loss of PDI activity; (3) Comparison of the sequence of the DHR of Nox2 with PDI family members revealed three small regions of homology with PDIA3; (4) Two monoclonal anti-Nox2 antibodies, with epitopes corresponding to regions of Nox2/PDIA3 homology, reacted with PDIA3 but not with PDIA1; (5) A polyclonal anti-PDIA3 (but not an anti-PDIA1) antibody reacted with Nox2; (6) p67 (phox) , in which all cysteines were mutated to serines, lost its ability to bind to a Nox2 peptide containing the CGC triad and had an impaired capacity to support oxidase activity in vitro. We propose a model of oxidase assembly in which binding of p67 (phox) to Nox2 via disulfide bonds, by virtue of the intrinsic PDI activity of Nox2, stabilizes

  7. Salmonella pathogenicity island 2-encoded type III secretion system mediates exclusion of NADPH oxidase assembly from the phagosomal membrane.

    Science.gov (United States)

    Gallois, A; Klein, J R; Allen, L A; Jones, B D; Nauseef, W M

    2001-05-01

    Salmonella typhimurium requires a type III secretion system encoded by pathogenicity island (SPI)-2 to survive and proliferate within macrophages. This survival implies that S. typhimurium avoids or withstands bactericidal events targeted to the microbe-containing vacuole, which include intraphagosomal production of reactive oxygen species (ROS), phagosomal acidification, and delivery of hydrolytic enzymes to the phagosome via fusion with lysosomes. Recent evidence suggests that S. typhimurium alters ROS production by murine macrophages in an SPI-2-dependent manner. To gain insights into the mechanism by which S. typhimurium inhibits intraphagosomal ROS production, we analyzed the subcellular distribution of NADPH oxidase components during infection of human monocyte-derived macrophages by wild-type (WT) or several SPI-2 mutant strains of S. typhimurium. We found that the membrane component of the NADPH oxidase, flavocytochrome b(558), was actively excluded or rapidly removed from the phagosomal membrane of WT-infected monocyte-derived macrophages, thereby preventing assembly of the NADPH oxidase complex and intraphagosomal production of superoxide anion. In contrast, the NADPH oxidase assembled on and generated ROS in phagosomes containing SPI-2 mutant S. typhimurium. Subversion of NADPH oxidase assembly by S. typhimurium was accompanied by increased bacterial replication relative to that of SPI-2 mutant strains, suggesting that the ability of WT S. typhimurium to prevent NADPH oxidase assembly at the phagosomal membrane represents an important virulence factor influencing its intracellular survival.

  8. Characterization of superoxide overproduction by the D-Loop(Nox4)-Nox2 cytochrome b(558) in phagocytes-Differential sensitivity to calcium and phosphorylation events.

    Science.gov (United States)

    Carrichon, Laure; Picciocchi, Antoine; Debeurme, Franck; Defendi, Federica; Beaumel, Sylvain; Jesaitis, Algirdas J; Dagher, Marie-Claire; Stasia, Marie-José

    2011-01-01

    NADPH oxidase is a crucial element of phagocytes involved in microbicidal mechanisms. It becomes active when membrane-bound cytochrome b(558), the redox core, is assembled with cytosolic p47(phox), p67(phox), p40(phox), and rac proteins to produce superoxide, the precursor for generation of toxic reactive oxygen species. In a previous study, we demonstrated that the potential second intracellular loop of Nox2 was essential to maintaining NADPH oxidase activity by controlling electron transfer from FAD to O(2). Moreover, replacement of this loop by the Nox4-D-loop (D-loop(Nox4)-Nox2) in PLB-985 cells induced superoxide overproduction. In the present investigation, we demonstrated that both soluble and particulate stimuli were able to induce this superoxide overproduction. Superoxide overproduction was also observed after phosphatidic acid activation in a purified cell-free-system assay. The highest oxidase activity was obtained after ionomycin and fMLF stimulation. In addition, enhanced sensitivity to Ca(2+) influx was shown by thapsigargin, EDTA, or BTP2 treatment before fMLF activation. Mutated cytochrome b(558) was less dependent on phosphorylation triggered by ERK1/2 during fMLF or PMA stimulation and by PI3K during OpZ stimulation. The superoxide overproduction of the D-loop(Nox4)-Nox2 mutant may come from a change of responsiveness to intracellular Ca(2+) level and to phosphorylation events during oxidase activation. Finally the D-loop(Nox4)-Nox2-PLB-985 cells were more effective against an attenuated strain of Pseudomonas aeruginosa compared to WT-Nox2 cells. The killing mechanism was biphasic, an early step of ROS production that was directly bactericidal, and a second oxidase-independent step related to the amount of ROS produced in the first step.

  9. Macrophages generate reactive oxygen species in response to minimally oxidized LDL: TLR4- and Syk-dependent activation of Nox2

    Science.gov (United States)

    Bae, Yun Soo; Lee, Jee Hyun; Choi, Soo Ho; Kim, Sunah; Almazan, Felicidad; Witztum, Joseph L.; Miller, Yury I.

    2009-01-01

    Oxidative modification of low-density lipoprotein (LDL) plays a causative role in the development of atherosclerosis. In this study, we demonstrate that minimally oxidized LDL (mmLDL) stimulates intracellular reactive oxygen species (ROS) generation in macrophages through NADPH oxidase 2 (gp91phox/Nox2), which in turn induces production of RANTES and migration of smooth muscle cells. Peritoneal macrophages from gp91phox/Nox2−/− mice or J774 macrophages in which Nox2 was knocked down by siRNA failed to generate ROS in response to mmLDL. Because mmLDL-induced cytoskeletal changes were dependent on TLR4, we analyzed ROS generation in peritoneal macrophages from wild type, TLR4−/−, or MyD88−/− mice and found that mmLDL-mediated ROS was generated in a TLR4-dependent, but MyD88-independent manner. Furthermore, we found that ROS generation required the recruitment and activation of spleen tyrosine kinase (Syk) and that mmLDL also induced PLCγ1 phosphorylation and PKC membrane translocation. Importantly, the PLCγ1 phosphorylation was reduced in J774 cells expressing Syk-specific shRNA. Nox2 modulated mmLDL activation of macrophages by regulating the expression of proinflammatory cytokines IL-1β, IL-6 and RANTES. We showed that purified RANTES was able to stimulate migration of mouse aortic smooth muscle cells (MASMC) and addition of neutralizing antibody against RANTES abolished the migration of MASMC stimulated by mmLDL-stimulated macrophages. These results suggest that mmLDL induces generation of ROS through sequential activation of TLR4, Syk, PLCγ1, PKC, and gp91phox/Nox2 and thereby stimulates expression of proinflammatory cytokines. These data help explain mechanisms by which endogenous ligands, such as mmLDL, can induce TLR4-dependent, proatherogenic activation of macrophages. PMID:19096031

  10. TMEM16A Contributes to Endothelial Dysfunction by Facilitating Nox2 NADPH Oxidase-Derived Reactive Oxygen Species Generation in Hypertension.

    Science.gov (United States)

    Ma, Ming-Ming; Gao, Min; Guo, Kai-Min; Wang, Mi; Li, Xiang-Yu; Zeng, Xue-Lin; Sun, Lu; Lv, Xiao-Fei; Du, Yan-Hua; Wang, Guan-Lei; Zhou, Jia-Guo; Guan, Yong-Yuan

    2017-03-20

    Ca2(+)-activated Cl(-) channels play a crucial role in various physiological processes. However, the role of TMEM16A in vascular endothelial dysfunction during hypertension is unclear. In this study, we investigated the specific involvement of TMEM16A in regulating endothelial function and blood pressure and the underlying mechanism. Reverse transcription-polymerase chain reaction, Western blotting, coimmunoprecipitation, confocal imaging, patch-clamp recordings, and TMEM16A endothelial-specific transgenic and knockout mice were used. We found that TMEM16A was expressed abundantly and functioned as a Ca2(+)-activated Cl(-) channel in endothelial cells. Angiotensin II induced endothelial dysfunction with an increase in TMEM16A expression. The knockout of endothelial-specific TMEM16A significantly lowered the blood pressure and ameliorated endothelial dysfunction in angiotensin II-induced hypertension, whereas the overexpression of endothelial-specific TMEM16A resulted in the opposite effects. These results were related to the increased reactive oxygen species production, Nox2-containing NADPH oxidase activation, and Nox2 and p22phox protein expression that were facilitated by TMEM16A on angiotensin II-induced hypertensive challenge. Moreover, TMEM16A directly bound with Nox2 and reduced the degradation of Nox2 through the proteasome-dependent degradation pathway. Therefore, TMEM16A is a positive regulator of endothelial reactive oxygen species generation via Nox2-containing NADPH oxidase, which induces endothelial dysfunction and hypertension. Modification of TMEM16A may be a novel therapeutic strategy for endothelial dysfunction-associated diseases.

  11. Phagosome maturation in unicellular eukaryote Paramecium: the presence of RILP, Rab7 and LAMP-2 homologues.

    Science.gov (United States)

    Wyroba, E; Surmacz, L; Osinska, M; Wiejak, J

    2007-01-01

    Phagosome maturation is a complex process enabling degradation of internalised particles. Our data obtained at the gene, protein and cellular level indicate that the set of components involved in this process and known up to now in mammalian cells is functioning in unicellular eukaryote. Rab7-interacting partners: homologues of its effector RILP (Rab-interacting lysosomal protein) and LAMP-2 (lysosomal membrane protein 2) as well as alpha7 subunit of the 26S proteasome were revealed in Paramecium phagolysosomal compartment. We identified the gene/transcript fragments encoding RILP-related proteins (RILP1 and RILP2) in Paramecium by PCR/RT-PCR and sequencing. The deduced amino acid sequences of RILP1 and RILP2 show 60.5% and 58.3% similarity, respectively, to the region involved in regulating of lysosomal morphology and dynein-dynactin recruitment of human RILP. RILP colocalised with Rab7 in Paramecium lysosomes and at phagolysosomal membrane during phagocytosis of both the latex beads and bacteria. In the same compartment LAMP-2 was present and its expression during latex internalisation was 2.5-fold higher than in the control when P2 protein fractions (100,000 x g) of equal load were quantified by immunoblotting. LAMP-2 cross-reacting polypeptide of approximately106 kDa was glycosylated as shown by fluorescent and Western analysis of the same blot preceded by PNGase F treatment. The alpha7 subunit of 26S proteasome was detected close to the phagosomal membrane in the small vesicles, in some of which it colocalised with Rab7. Immunoblotting confirmed presence of RILP-related polypeptide and a7 subunit of 26S proteasome in Paramecium protein fractions. These results suggest that Rab7, RILP and LAMP-2 may be involved in phagosome maturation in Paramecium.

  12. Phagosome maturation in unicellular eukaryote Paramecium: the presence of RILP, Rab7 and LAMP-2 homologues

    Directory of Open Access Journals (Sweden)

    E Wyroba

    2009-08-01

    Full Text Available Phagosome maturation is a complex process enabling degradation of internalised particles. Our data obtained at the gene, protein and cellular level indicate that the set of components involved in this process and known up to now in mammalian cells is functioning in unicellular eukaryote. Rab7-interacting partners: homologues of its effector RILP (Rab-interacting lysosomal protein and LAMP-2 (lysosomal membrane protein 2 as well as a7 subunit of the 26S proteasome were revealed in Paramecium phagolysosomal compartment. We identified the gene/transcript fragments encoding RILP-related proteins (RILP1 and RILP2 in Paramecium by PCR/RT-PCR and sequencing. The deduced amino acid sequences of RILP1 and RILP2 show 60.5% and 58.3% similarity, respectively, to the region involved in regulating of lysosomal morphology and dynein-dynactin recruitment of human RILP. RILP colocalised with Rab7 in Paramecium lysosomes and at phagolysosomal membrane during phagocytosis of both the latex beads and bacteria. In the same compartment LAMP-2 was present and its expression during latex internalisation was 2.5-fold higher than in the control when P2 protein fractions (100 000 x g of equal load were quantified by immunoblotting. LAMP-2 crossreacting polypeptide of ~106 kDa was glycosylated as shown by fluorescent and Western analysis of the same blot preceded by PNGase F treatment. The a7 subunit of 26S proteasome was detected close to the phagosomal membrane in the small vesicles, in some of which it colocalised with Rab7. Immunoblotting confirmed presence of RILPrelated polypeptide and a7 subunit of 26S proteasome in Paramecium protein fractions. These results suggest that Rab7, RILP and LAMP-2 may be involved in phagosome maturation in Paramecium.

  13. Evidence for the involvement of ActA in maturation of the Listeria monocytogenes phagosome

    Institute of Scientific and Technical Information of China (English)

    Mathilde A Poussin; Howard Goldfine

    2010-01-01

    @@ Dear Editor, Listeria monocytogenes (Lm), a Gram-positive facultative bacterium, is the causative agent of listeriosis, a food-borne disease affecting humans [1]. During infections, Lm enters phagosomes from which it escapes into the cytoplasm. Listeriolysin O (LLO) is essential, and two phospholipases play a role in this process [1]. Actin polymerization provides the propulsive force that moves the bacteria through the cytoplasm and into adjacent cells. It is initiated by the interaction of the N-terminal domain of ActA, a 639 amino acid membrane protein, with the host Arp2/3 complex.

  14. Probucol inhibited Nox2 expression and attenuated podocyte injury in type 2 diabetic nephropathy of db/db mice.

    Science.gov (United States)

    Zhou, Guangyu; Wang, Yanqiu; He, Ping; Li, Detian

    2013-01-01

    The present study was conducted to investigate the effects of probucol on the progression of diabetic nephropathy and the underlying mechanism in type 2 diabetic db/db mice. Eight weeks db/db mice were treated with regular diet or probucol-containing diet (1%) for 12 weeks. Non-diabetic db/m mice were used as controls. We examined body weight, blood glucose, and urinary albumin. At 20 weeks, experimental mice were sacrificed and their blood and kidneys were extracted for the analysis of blood chemistry, kidney histology, oxidative stress marker, and podocyte marker. As a result, 24 h urinary albumin excretions were reduced after probucol treatment. There were improvements of extracellular matrix accumulation and fibronectin and collagen IV deposition in glomeruli in the probucol-treated db/db mice. The reduction of nephrin and the loss of podocytes were effectively prevented by probucol in db/db mice. Furthermore, probucol significantly decreased the production of thiobarbituric acid-reactive substances (TBARS), an index of reactive oxygen species (ROS) generation and down-regulated the expression of Nox2. Taken together, our findings support that probucol may have the potential to protect against type 2 diabetic nephropathy via amelioration of podocyte injury and reduction of oxidative stress.

  15. Akt and SHIP modulate Francisella escape from the phagosome and induction of the Fas-mediated death pathway.

    Directory of Open Access Journals (Sweden)

    Murugesan V S Rajaram

    Full Text Available Francisella tularensis infects macrophages and escapes phago-lysosomal fusion to replicate within the host cytosol, resulting in host cell apoptosis. Here we show that the Fas-mediated death pathway is activated in infected cells and correlates with escape of the bacterium from the phagosome and the bacterial burden. Our studies also demonstrate that constitutive activation of Akt, or deletion of SHIP, promotes phago-lysosomal fusion and limits bacterial burden in the host cytosol, and the subsequent induction of Fas expression and cell death. Finally, we show that phagosomal escape/intracellular bacterial burden regulate activation of the transcription factors sp1/sp3, leading to Fas expression and cell death. These data identify for the first time host cell signaling pathways that regulate the phagosomal escape of Francisella, leading to the induction of Fas and subsequent host cell death.

  16. FLEXIBLE GEIGER COUNTER

    Science.gov (United States)

    Richter, H.G.; Gillespie, A.S. Jr.

    1963-11-12

    A flexible Geiger counter constructed from materials composed of vinyl chloride polymerized with plasticizers or co-polymers is presented. The counter can be made either by attaching short segments of corrugated plastic sleeving together, or by starting with a length of vacuum cleaner hose composed of the above materials. The anode is maintained substantially axial Within the sleeving or hose during tube flexing by means of polystyrene spacer disks or an easily assembled polyethylene flexible cage assembly. The cathode is a wire spiraled on the outside of the counter. The sleeving or hose is fitted with glass end-pieces or any other good insulator to maintain the anode wire taut and to admit a counting gas mixture into the counter. Having the cathode wire on the outside of the counter substantially eliminates the objectional sheath effect of prior counters and permits counting rates up to 300,000 counts per minute. (AEC)

  17. Countering Internet Extremism

    Science.gov (United States)

    2009-01-01

    literally examine hundreds of books and speeches. Since the purpose of this work is examining ways to counter an extremist’s Internet use of the...provide differing perspectives on how to counter extremist Internet use . A 2008 New York Times article indirectly offers some methods. Writers Eric...or scholars have the most potential to effectively counter extremist Internet use . Such efforts could help to stifle some of the issues that

  18. Nox2 modification of LDL is essential for optimal apolipoprotein B-mediated control of agr type III Staphylococcus aureus quorum-sensing.

    Directory of Open Access Journals (Sweden)

    Pamela R Hall

    2013-02-01

    Full Text Available Staphylococcus aureus contains an autoinducing quorum-sensing system encoded within the agr operon that coordinates expression of virulence genes required for invasive infection. Allelic variation within agr has generated four agr specific groups, agr I-IV, each of which secretes a distinct autoinducing peptide pheromone (AIP1-4 that drives agr signaling. Because agr signaling mediates a phenotypic change in this pathogen from an adherent colonizing phenotype to one associated with considerable tissue injury and invasiveness, we postulated that a significant contribution to host defense against tissue damaging and invasive infections could be provided by innate immune mechanisms that antagonize agr signaling. We determined whether two host defense factors that inhibit AIP1-induced agrI signaling, Nox2 and apolipoprotein B (apoB, also contribute to innate control of AIP3-induced agrIII signaling. We hypothesized that apoB and Nox2 would function differently against AIP3, which differs from AIP1 in amino acid sequence and length. Here we show that unlike AIP1, AIP3 is resistant to direct oxidant inactivation by Nox2 characteristic ROS. Rather, the contribution of Nox2 to defense against agrIII signaling is through oxidation of LDL. ApoB in the context of oxLDL, and not LDL, provides optimal host defense against S. aureus agrIII infection by binding the secreted signaling peptide, AIP3, and preventing expression of the agr-driven virulence factors which mediate invasive infection. ApoB within the context of oxLDL also binds AIP 1-4 and oxLDL antagonizes agr signaling by all four agr alleles. Our results suggest that Nox2-mediated oxidation of LDL facilitates a conformational change in apoB to one sufficient for binding and sequestration of all four AIPs, demonstrating the interdependence of apoB and Nox2 in host defense against agr signaling. These data reveal a novel role for oxLDL in host defense against S. aureus quorum-sensing signaling.

  19. Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics

    Energy Technology Data Exchange (ETDEWEB)

    Manes, Nathan P.; Gustin, Jean K.; Rue, Joanne; Mottaz, Heather M.; Purvine, Samuel O.; Norbeck, Angela D.; Monroe, Matthew E.; Zimmer, Jennifer S.; Metz, Thomas O.; Adkins, Joshua N.; Smith, Richard D.; Heffron, Fred

    2007-04-01

    The pathogen Salmonella enterica is known to cause both food poisoning and typhoid fever. Due to the emergence of antibiotic-resistant isolates and the threat of bioterrorism (e.g., contamination of the food supply), there is a growing need to study this bacterium. In this investigation, comparative peptidomics was used to study Salmonella enterica serovar Typhimurium cultured in either a rich medium or in an acidic, low magnesium, and minimal nutrient medium designed to roughly mimic the macrophage phagosomal compartment (within which Salmonella are known to survive). Native peptides from cleared cell lysates were enriched by using isopropanol extraction and analyzed by using both LC-MS/MS and LC-FTICR-MS. We identified 5,163 distinct peptides originating from 682 proteins and the data clearly indicated that compared to cells cultured in the rich medium, Salmonella cultured in the phagosome-mimicking medium had dramatically higher abundances of a wide variety of protein degradation products, especially from ribosomal proteins. Salmonella from the same cultures were also analyzed by using bottom-up proteomics, and when the peptidomic and proteomic data were analyzed together, two clusters of proteins targeted for proteolysis were tentatively identified. Possible roles of targeted proteolysis by phagocytosed Salmonella are discussed.

  20. Cholesterol glucosylation by Helicobacter pylori delays internalization and arrests phagosome maturation in macrophages.

    Science.gov (United States)

    Du, Shin-Yi; Wang, Hung-Jung; Cheng, Hsin-Hung; Chen, Sheng-De; Wang, Lily Hui-Ching; Wang, Wen-Ching

    2016-10-01

    Helicobacter pylori colonizes the human stomach and contributes to chronic inflammation of the gastric mucosa. H. pylori persistence occurs because of insufficient eradication by phagocytic cells. A key factor of H. pylori, cholesterol-α-glucosyltransferase encoded by capJ that extracts host cholesterol and converts it to cholesteryl glucosides, is important to evade host immunity. Here, we examined whether phagocytic trafficking in macrophages was perturbed by capJ-carrying H. pylori. J774A.1 cells were infected with H. pylori at a multiplicity of infection of 50. Live-cell imaging and confocal microscopic analysis were applied to monitor the phagocytic trafficking events. The viability of H. pylori inside macrophages was determined by using gentamicin colony-forming unit assay. The phagocytic routes were characterized by using trafficking-intervention compounds. Wild type (WT) H. pylori exhibited more delayed entry into macrophages and also arrested phagosome maturation more than did capJ knockout mutant. Pretreatment of genistein and LY294002 prior to H. pylori infection reduced the internalization of WT but not capJ-knockout H. pylori in macrophages. Cholesterol glucosylation by H. pylori interferes with phagosome trafficking via a lipid-raft and PI3K-dependent manner, which retards engulfment of bacteria for prolonged intracellular survival of H. pylori. Copyright © 2014. Published by Elsevier B.V.

  1. Phagosomal degradation increases TLR access to bacterial ligands and enhances macrophage sensitivity to bacteria

    Science.gov (United States)

    Wolf, Andrea J.; Arruda, Andrea; Reyes, Christopher N.; Kaplan, Amber T.; Shimada, Takahiro; Shimada, Kenichi; Arditi, Moshe; Liu, George; Underhill, David M.

    2011-01-01

    Signaling by innate immune receptors initiates and orchestrates the overall immune responses to infection. Macrophage receptors recognizing pathogens can be broadly grouped into surface receptors and receptors restricted to intracellular compartments, such as phagosomes and the cytoplasm. There is an expectation that ingestion and degradation of microorganisms by phagocytes contributes to activation of intracellular innate receptors, although direct demonstrations of this are rare and many model ligands are studied in soluble form, outside of their microbial context. By comparing a wild-type strain of Staphylococcus aureus and a lysozyme-sensitive mutant, we have been able to directly address the role of degradation of live bacteria by mouse macrophages in determining the overall innate cellular inflammatory response. Our investigations revealed a biphasic response to S. aureus that consisted of an initial signal resulting from the engagement of surface TLR2, followed by a later, second wave on inflammatory gene induction. This second wave of inflammatory signaling was dependent on and correlated with the timing of bacterial degradation in phagosomes. We found that TLR2 signaling followed by TLR2/TLR9 signaling enhanced sensitivity to small numbers of bacteria. We further found that treating wild-type bacteria with the peptidoglycan synthesis-inhibiting antibiotic vancomycin made S. aureus more susceptible to degradation and resulted in increased inflammatory responses, similar to those observed for mutant degradation-sensitive bacteria. PMID:22031762

  2. The phagosomal transporter A couples threonine acquisition to differentiation and replication of Legionella pneumophila in macrophages.

    Science.gov (United States)

    Sauer, John-Demian; Bachman, Michael A; Swanson, Michele S

    2005-07-12

    Differentiation in response to environmental cues is integral to the success of many intracellular pathogens. By characterizing a Legionella pneumophila mutant defective for differentiation in broth and replication in macrophages, we identified a subfamily of major facilitator superfamily transporters, here named Pht (phagosomal transporter), that also is conserved in two other vacuolar pathogens, Coxiella burnetii and Francisella tularensis. Biolog phenotype microarray analysis indicated that PhtA transports threonine, an essential amino acid. Either excess threonine or threonine peptides bypass phtA function. In minimal medium, phtA mutants do not replicate; in rich broth, the bacteria prematurely differentiate to the transmissive phase, as judged by the kinetics of flaA-gfp expression, heat resistance, and sodium sensitivity. PhtA is dispensable for transmissive L. pneumophila to establish and persist within a replication vacuole but is essential for their differentiation to the replicative phase, based on phenotypic and RT-PCR analysis. Accordingly, we propose that the Pht transporter family equips transmissive L. pneumophila, C. burnetii, and F. tularensis to assess their phagosomal nutrient supply before committing to reenter the cell cycle.

  3. Anticoincidence scintillation counter

    CERN Multimedia

    1966-01-01

    This anticoincidence scintillation counter will be mounted in a hydrogen target vessel to be used in a measurement of the .beta. parameter in the .LAMBDA0. decay. The geometry of the counter optimizes light collection in the central part where a scintillation disk of variable thickness can be fitted.

  4. Proportional counter radiation camera

    Science.gov (United States)

    Borkowski, C.J.; Kopp, M.K.

    1974-01-15

    A gas-filled proportional counter camera that images photon emitting sources is described. A two-dimensional, positionsensitive proportional multiwire counter is provided as the detector. The counter consists of a high- voltage anode screen sandwiched between orthogonally disposed planar arrays of multiple parallel strung, resistively coupled cathode wires. Two terminals from each of the cathode arrays are connected to separate timing circuitry to obtain separate X and Y coordinate signal values from pulse shape measurements to define the position of an event within the counter arrays which may be recorded by various means for data display. The counter is further provided with a linear drift field which effectively enlarges the active gas volume of the counter and constrains the recoil electrons produced from ionizing radiation entering the counter to drift perpendicularly toward the planar detection arrays. A collimator is interposed between a subject to be imaged and the counter to transmit only the radiation from the subject which has a perpendicular trajectory with respect to the planar cathode arrays of the detector. (Official Gazette)

  5. The first CEDAR counter

    CERN Multimedia

    1976-01-01

    The first differential Cerenkov counter with chromatic corrections (called CEDAR) successfully tested at the PS in July 75. These counters were used in the SPS hadronic beams for particle identification. Some of the eight photomultipliers can be seen: they receive the light reflected back through the annular diaphragm. René Maleyran stands on the left.

  6. Weight loss is associated with improved endothelial dysfunction via NOX2-generated oxidative stress down-regulation in patients with the metabolic syndrome.

    Science.gov (United States)

    Angelico, Francesco; Loffredo, Lorenzo; Pignatelli, Pasquale; Augelletti, Teresa; Carnevale, Roberto; Pacella, Antonio; Albanese, Fabiana; Mancini, Ilaria; Di Santo, Serena; Del Ben, Maria; Violi, Francesco

    2012-06-01

    The aim of this study was to assess whether adherence to a restricted-calorie, Mediterranean-type diet improves endothelial dysfunction and markers of oxidative stress in patients with metabolic syndrome. A moderately low-calorie (600 calories/day negative energy balance), low-fat, high-carbohydrate diet (syndrome. Participants were divided into two groups according to body weight loss > or syndrome. The coexistent decrease of NOX2 activation suggests a role for oxidative stress in eliciting artery dysfunction.

  7. NOX2-Mediated TFEB Activation and Vacuolization Regulate Lysosome-Associated Cell Death Induced by Gypenoside L, a Saponin Isolated from Gynostemma pentaphyllum.

    Science.gov (United States)

    Zheng, Kai; Jiang, Yingchun; Liao, Chenghui; Hu, Xiaopeng; Li, Yan; Zeng, Yong; Zhang, Jian; Wu, Xuli; Wu, Haiqiang; Liu, Lizhong; Wang, Yifei; He, Zhendan

    2017-08-09

    Downregulation of apoptotic signal pathway and activation of protective autophagy mainly contribute to the chemoresistance of tumor cells. Therefore, exploring efficient chemotherapeutic agents or isolating novel natural products that can trigger nonapoptotic and nonautophagic cell death such as lysosome-associated death is emergently required. We have recently extracted a saponin, gypenoside L (Gyp-L), from Gynostemma pentaphyllum and showed that Gyp-L was able to induce nonapoptotic cell death of esophageal cancer cells associated with lysosome swelling. However, contributions of vacuolization and lysosome to cell death remain unclear. Herein, we reveal a critical role for NADPH oxidase NOX2-mediated vacuolization and transcription factor EB (TFEB) activation in lysosome-associated cell death. We found that Gyp-L initially induced the abnormal enlarged and alkalized vacuoles, which were derived from lipid rafts dependent endocytosis. Besides, NOX2 was activated to promote vacuolization and mTORC1-independent TFEB-mediated lysosome biogenesis. Finally, raising lysosome pH could enhance Gyp-L induced cell death. These findings suggest a protective role of NOX2-TFEB-mediated lysosome biogenesis in cancer drug resistance and the tight interaction between lipid rafts and vacuolization. In addition, Gyp-L can be utilized as an alternative option to overcome drug-resistance though inducing lysosome associated cell death.

  8. The ability of Listeria monocytogenes PI-PLC to facilitate escape from the macrophage phagosome is dependent on host PKCbeta.

    Science.gov (United States)

    Poussin, Mathilde A; Leitges, Michael; Goldfine, Howard

    2009-01-01

    Listeria monocytogenes are facultative intracellular pathogenic bacteria that can infect macrophages as well as non-professional phagocytes. After entry in the host cell, the bacteria escape from the phagosome into the cytoplasm. In murine macrophages and in cell lines derived from these cells, escape of L. monocytogenes from the phagosome is absolutely dependent on listeriolysin O (LLO) and facilitated by a secreted phosphatidylinositol-specific phospholipase C (PI-PLC). Work in this laboratory has previously demonstrated a LLO and PI-PLC-dependent translocation of host PKCbeta isoforms. Pharmacological inhibition of PKCbeta resulted in a significant reduction in permeabilization of the phagosome, and in the number of bacteria reaching the cytosol. These findings led to the prediction that the bacterial PI-PLC promotes escape through the production of diacylglycerol leading to the activation of host PKCbeta. To test this hypothesis, bone marrow-derived macrophages (BMMf) obtained from PKCbeta knockout (PKCbetaKO) or C57Bl/6 mice were infected with L. monocytogenes. We observed that wild-type L. monocytogenes escapes from the phagosome of PKCbetaKO BMMf as well as from C57Bl/6 BMMf. However, in PKCbetaKO BMMf, L. monocytogenes uses a PI-PLC-independent, but phosphatidylcholine-preferring PLC (PC-PLC)-dependent pathway to facilitate escape. These findings strongly support the hypothesis that PI-PLC promotes escape through mobilization of host PKCbeta.

  9. Birc1e/Naip5 rapidly antagonizes modulation of phagosome maturation by Legionella pneumophila.

    Science.gov (United States)

    Fortier, Anne; de Chastellier, Chantal; Balor, Stéphanie; Gros, Philippe

    2007-04-01

    Legionella survives intracellularly by preventing fusion with lysosomes, due to phagosome escape from the endocytic pathway at an early stage of phagosome maturation, and by creating a replicative organelle that acquires endoplasmic reticulum (ER) characteristics through sustained interactions and fusion with the ER. Intracellular replication of Legionella pneumophila in mouse macrophages is controlled by the Lgn1 locus. Functional complementation in vivo has identified the Birc1e/Naip5 gene as being responsible for the Lgn1 effect. To understand the function and temporal site of action of Birc1e/Naip5 in susceptibility to L. pneumophila, we examined the biogenesis of Legionella-containing vacuoles (LCVs) formed in permissive A/J macrophages and in their Birc1e/Naip5 transgenic non-permissive counterpart. Birc1e/Naip5 effects on acquisition of lysosomal and ER markers were evident within 1-2 h following infection. A significantly higher proportion of LCVs formed in Birc1e/Naip5 transgenic macrophages had acquired the lysosomal markers cathepsin D and Lamp1 by 2 h post infection, whereas a significantly higher proportion of LCVs formed in permissive macrophages were positively stained for the ER markers BAP31 and calnexin, 6 h post infection. Likewise, studies by electron microscopy showed acquisition of lysosomal contents (horseradish peroxidase), within the first hour following phagocytic uptake, by LCVs formed in Birc1e/Naip5 transgenic macrophages and delivery of the ER marker glucose 6-phosphatase (G6Pase) only to the lumen of LCVs formed in A/J macrophages. Finally, a larger proportion of LCVs formed in A/J macrophages were studded with ribosomes 24 h post infection, compared with LCVs formed in Birc1e/Naip5 transgenic macrophages. These results suggest that sensing of L. pneumophila products by Birc1e/Naip5 in macrophages occurs rapidly following phagocytosis, a process that antagonizes the ability of L. pneumophila to remodel its phagosome into a specialized

  10. Effects of zinc oxide nanoparticles on Kupffer cell phagosomal motility, bacterial clearance, and liver function

    Directory of Open Access Journals (Sweden)

    Watson CY

    2015-06-01

    Full Text Available Christa Y Watson, Ramon M Molina, Andressa Louzada, Kimberly M Murdaugh, Thomas C Donaghey, Joseph D BrainCenter for Nanotechnology and Nanotoxicology, Molecular and Integrative Physiological Sciences Program, Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USABackground: Zinc oxide engineered nanoparticles (ZnO ENPs have potential as nanomedicines due to their inherent properties. Studies have described their pulmonary impact, but less is known about the consequences of ZnO ENP interactions with the liver. This study was designed to describe the effects of ZnO ENPs on the liver and Kupffer cells after intravenous (IV administration.Materials and methods: First, pharmacokinetic studies were conducted to determine the tissue distribution of neutron-activated 65ZnO ENPs post-IV injection in Wistar Han rats. Then, a noninvasive in vivo method to assess Kupffer cell phagosomal motility was employed using ferromagnetic iron particles and magnetometry. We also examined whether prior IV injection of ZnO ENPs altered Kupffer cell bactericidal activity on circulating Pseudomonas aeruginosa. Serum and liver tissues were collected to assess liver-injury biomarkers and histological changes, respectively.Results: We found that the liver was the major site of initial uptake of 65ZnO ENPs. There was a time-dependent decrease in tissue levels of 65Zn in all organs examined, reflecting particle dissolution. In vivo magnetometry showed a time-dependent and transient reduction in Kupffer cell phagosomal motility. Animals challenged with P. aeruginosa 24 hours post-ZnO ENP injection showed an initial (30 minutes delay in vascular bacterial clearance. However, by 4 hours, IV-injected bacteria were cleared from the blood, liver, spleen, lungs, and kidneys. Seven days post-ZnO ENP injection, creatine phosphokinase and aspartate aminotransferase levels in serum were significantly increased. Histological evidence of

  11. Atg8 is involved in endosomal and phagosomal acidification in the parasitic protist Entamoeba histolytica.

    Science.gov (United States)

    Picazarri, Karina; Nakada-Tsukui, Kumiko; Tsuboi, Kumiko; Miyamoto, Eri; Watanabe, Naoko; Kawakami, Eiryo; Nozaki, Tomoyoshi

    2015-10-01

    Autophagy is one of two major bulk protein degradation systems and is conserved throughout eukaryotes. The protozoan Entamoeba histolytica, which is a human intestinal parasite, possesses a restricted set of autophagy-related (Atg) proteins compared with other eukaryotes and thus represents a suitable model organism for studying the minimal essential components and ancestral functions of autophagy. E. histolytica possesses two conjugation systems: Atg8 and Atg5/12, although a gene encoding Atg12 is missing in the genome. Atg8 is considered to be the central and authentic marker of autophagosomes, but recent studies have demonstrated that Atg8 is not exclusively involved in autophagy per se, but other fundamental mechanisms of vesicular traffic. To investigate this question in E. histolytica, we studied on Atg8 during the proliferative stage. Atg8 was constitutively expressed in both laboratory-maintained and recently established clinical isolates and appeared to be lipid-modified in logarithmic growth phase, suggesting a role of Atg8 in non-stress and proliferative conditions. These findings are in contrast to those for Entamoeba invadens, in which autophagy is markedly induced during an early phase of differentiation from the trophozoite into the cyst. The repression of Atg8 gene expression in En. histolytica by antisense small RNA-mediated transcriptional gene silencing resulted in growth retardation, delayed endocytosis and reduced acidification of endosomes and phagosomes. Taken together, these results suggest that Atg8 and the Atg8 conjugation pathway have some roles in the biogenesis of endosomes and phagosomes in this primitive eukaryote.

  12. The Monomeric GTPase Rab35 Regulates Phagocytic Cup Formation and Phagosomal Maturation in Entamoeba histolytica.

    Science.gov (United States)

    Verma, Kuldeep; Datta, Sunando

    2017-03-24

    One of the hallmarks of amoebic colitis is the detection of Entamoeba histolytica (Eh) trophozoites with ingested erythrocytes. Therefore, erythrophagocytosis is traditionally considered as one of the most important criteria to identify the pathogenic behavior of the amoebic trophozoites. Phagocytosis is an essential process for the proliferation and virulence of this parasite. Phagocytic cargo, upon internalization, follows a defined trafficking route to amoebic lysosomal degradation machinery. Here, we demonstrated the role of EhRab35 in the early and late phases of erythrophagocytosis by the amoeba. EhRab35 showed large vacuolar as well as punctate vesicular localization. The spatiotemporal dynamics of vacuolar EhRab35 and its exchange with soluble cytosolic pool were monitored by fluorescence recovery after photobleaching experiments. Using extensive microscopy and biochemical methods, we demonstrated that upon incubation with RBCs EhRab35 is recruited to the site of phagocytic cups as well as to the nascent phagosomes that harbor Gal/GalNAc lectin and actin. Overexpression of a dominant negative mutant of EhRab35 reduced phagocytic cup formation and thereby reduced RBC internalization, suggesting a potential role of the Rab GTPase in the cup formation. Furthermore, we also performed a phagosomal maturation assay and observed that the activated form of EhRab35 significantly increased the rate of RBC degradation. Interestingly, this mutant also significantly enhanced the number of acidic compartments in the trophozoites. Taken together, our results suggest that EhRab35 is involved in the initial stage of phagocytosis as well as in the phagolysosomal biogenesis in E. histolytica and thus contributes to the pathogenicity of the parasite. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. A large Cerenkov counter

    CERN Multimedia

    1981-01-01

    The photo shows the vertex Cerenkov counter C0 back side (with 12 mirrors) of the NA9 experiment. On foreground are members of the team (CERN and Wuppertal Uni), Salvo .., Manfred Poetsch, ..., Jocelyn Thadome, Helmut Braun, Heiner Brueck.

  14. Counter-cryptanalysis

    NARCIS (Netherlands)

    M.M.J. Stevens (Marc); R. Canetti; J.A. Garay

    2013-01-01

    textabstractWe introduce \\emph{counter-cryptanalysis} as a new paradigm for strengthening weak cryptographic primitives against cryptanalytic attacks. Redesigning a weak primitive to more strongly resist cryptanalytic techniques will unavoidably break backwards compatibility. Instead,

  15. Comparison of a designed virtual counter with a real counter

    Science.gov (United States)

    Tektas, G.; Celiktas, C.

    2017-02-01

    A counter is a device which counts the incident pulses within a fixed time. In this work, a virtual counter was designed by developing a code by LabVIEW software. Generator signals were sent to the virtual counter via a National Instruments multifunction data acquisition device. Analog and PFI (Programmable Function Interface) inputs of the device was used for the process. A real counter was also used for comparison. Counts acquired from both counters in different time intervals were compared with each other. It was concluded from the obtained results that the developed virtual counter could be used as a real counter.

  16. Phagocyte-like NADPH oxidase (Nox2) promotes activation of p38MAPK in pancreatic β-cells under glucotoxic conditions: Evidence for a requisite role of Ras-related C3 botulinum toxin substrate 1 (Rac1).

    Science.gov (United States)

    Sidarala, Vaibhav; Veluthakal, Rajakrishnan; Syeda, Khadija; Vlaar, Cornelis; Newsholme, Philip; Kowluru, Anjaneyulu

    2015-06-15

    It is well established that glucotoxicity (caused by high glucose concentrations; HG) underlies pathogenesis of islet dysfunction in diabetes. We have recently demonstrated that Nox2 plays a requisite role in the generation of reactive oxygen species (ROS) under HG conditions, resulting in mitochondrial dysregulation and loss of islet β-cell function. Herein, we investigated roles of Nox2 in the regulation of downstream stress kinase (p38MAPK) activation under HG conditions (20mM; 24h) in normal rodent islets and INS-1 832/13 cells. We observed that gp91-ds-tat, a specific inhibitor of Nox2, but not its inactive analog, significantly attenuated HG-induced Nox2 activation, ROS generation and p38MAPK activation, thus suggesting that Nox2 activation couples with p38MAPK activation. Since Rac1, is an integral member of the Nox2 holoenzyme, we also assessed the effects of Rac1 inhibitors (EHT 1864, NSC23766 and Ehop-016) on HG-induced p38MAPK activation in isolated β-cells. We report a significant inhibition of p38MAPK phosphorylation by Rac1 inhibitors, implying a regulatory role for Rac1 in promoting the Nox2-p38MAPK signaling axis in the β-cell under the duress of HG. 2-Bromopalmitate, a known inhibitor of protein (Rac1) palmitoylation, significantly reduced HG-induced p38MAPK phosphorylation. However, GGTI-2147, a specific inhibitor of geranylgeranylation of Rac1, failed to exert any significant effects on HG-induced p38MAPK activation. In conclusion, we present the first evidence that the Rac1-Nox2 signaling module plays novel regulatory roles in HG-induced p38MAPK activation and loss in glucose-stimulated insulin secretion (GSIS) culminating in metabolic dysfunction and the onset of diabetes. Copyright © 2015. Published by Elsevier Inc.

  17. NADPH Oxidases NOX-1 and NOX-2 Require the Regulatory Subunit NOR-1 To Control Cell Differentiation and Growth in Neurospora crassa▿ †

    Science.gov (United States)

    Cano-Domínguez, Nallely; Álvarez-Delfín, Karen; Hansberg, Wilhelm; Aguirre, Jesús

    2008-01-01

    We have proposed that reactive oxygen species (ROS) play essential roles in cell differentiation. Enzymes belonging to the NADPH oxidase (NOX) family produce superoxide in a regulated manner. We have identified three distinct NOX subfamilies in the fungal kingdom and have shown that NoxA is required for sexual cell differentiation in Aspergillus nidulans. Here we show that Neurospora crassa NOX-1 elimination results in complete female sterility, decreased asexual development, and reduction of hyphal growth. The lack of NOX-2 did not affect any of these processes but led instead to the production of sexual spores that failed to germinate, even in the presence of exogenous oxidants. The elimination of NOR-1, an ortholog of the mammalian Nox2 regulatory subunit gp67phox, also caused female sterility, the production of unviable sexual spores, and a decrease in asexual development and hyphal growth. These results indicate that NOR-1 is required for NOX-1 and NOX-2 functions at different developmental stages and establish a link between NOX-generated ROS and the regulation of growth. Indeed, NOX-1 was required for the increased asexual sporulation previously observed in mutants without catalase CAT-3. We also analyzed the function of the penta-EF calcium-binding domain protein PEF-1 in N. crassa. Deletion of pef-1 resulted in increased conidiation but, in contrast to what occurs in Dictyostelium discoideum, the mutation of this peflin did not suppress the phenotypes caused by the lack of NOX-1. Our results support the role of ROS as critical cell differentiation signals and highlight a novel role for ROS in regulation of fungal growth. PMID:18567788

  18. Tropheryma whipplei, the agent of Whipple's disease, affects the early to late phagosome transition and survives in a Rab5- and Rab7-positive compartment.

    Directory of Open Access Journals (Sweden)

    Giovanna Mottola

    Full Text Available Tropheryma whipplei, the agent of Whipple's disease, inhibits phago-lysosome biogenesis to create a suitable niche for its survival and replication in macrophages. To understand the mechanism by which it subverts phagosome maturation, we used biochemical and cell biological approaches to purify and characterise the intracellular compartment where Tropheryma whipplei resides using mouse bone-marrow-derived macrophages. We showed that in addition to Lamp-1, the Tropheryma whipplei phagosome is positive for Rab5 and Rab7, two GTPases required for the early to late phagosome transition. Unlike other pathogens, inhibition of PI(3P production was not the mechanism for Rab5 stabilisation at the phagosome. Overexpression of the inactive, GDP-bound form of Rab5 bypassed the pathogen-induced blockade of phago-lysosome biogenesis. This suggests that Tropheryma whipplei blocks the switch from Rab5 to Rab7 by acting on the Rab5 GTPase cycle. A bio-informatic analysis of the Tropheryma whipplei genome revealed a glyceraldehyde-3-phosphate dehydrogenase (GAPDH homologous with the GAPDH of Listeria monocytogenes, and this may be the bacterial protein responsible for blocking Rab5 activity. To our knowledge, Tropheryma whipplei is the first pathogen described to induce a "chimeric" phagosome stably expressing both Rab5 and Rab7, suggesting a novel and specific mechanism for subverting phagosome maturation.

  19. MUNC13-4 protein regulates the oxidative response and is essential for phagosomal maturation and bacterial killing in neutrophils.

    Science.gov (United States)

    Monfregola, Jlenia; Johnson, Jennifer Linda; Meijler, Michael M; Napolitano, Gennaro; Catz, Sergio Daniel

    2012-12-28

    Neutrophils use diverse mechanisms to kill pathogens including phagocytosis, exocytosis, generation of reactive oxygen species (ROS), and neutrophil extracellular traps. These mechanisms rely on their ability to mobilize intracellular organelles and to deliver granular cargoes to specific cellular compartments or into the extracellular milieu, but the molecular mechanisms regulating vesicular trafficking in neutrophils are not well understood. MUNC13-4 is a RAB27A effector that coordinates exocytosis in hematopoietic cells, and its deficiency is associated with the human immunodeficiency familial hemophagocytic lymphohistiocytosis type 3. In this work, we have established an essential role for MUNC13-4 in selective vesicular trafficking, phagosomal maturation, and intracellular bacterial killing in neutrophils. Using neutrophils from munc13-4 knock-out (KO) mice, we show that MUNC13-4 is necessary for the regulation of p22(phox)-expressing granule trafficking to the plasma membrane and regulates extracellular ROS production. MUNC13-4 was also essential for the regulation of intracellular ROS production induced by Pseudomonas aeruginosa despite normal trafficking of p22(phox)-expressing vesicles toward the phagosome. Importantly, in the absence of MUNC13-4, phagosomal maturation was impaired as observed by the defective delivery of azurophilic granules and multivesicular bodies to the phagosome. Significantly, this mechanism was intact in RAB27A KO neutrophils. Intracellular bacterial killing was markedly impaired in MUNC13-4 KO neutrophils. MUNC13-4-deficient cells showed a significant increase in neutrophil extracellular trap formation but were unable to compensate for the impaired bacterial killing. Altogether, these findings characterize novel functions of MUNC13-4 in the innate immune response of the neutrophil and have direct implications for the understanding of immunodeficiencies in patients with MUNC13-4 deficiency.

  20. An efficient anticoincidence counter

    CERN Multimedia

    1977-01-01

    This scintillation counter (about 25 cm diameter) was prepared at CERN for an experiment at the Saclay 600 MeV electron linac studying molecular processes originated in liquid hydrogen by muons. The counter is meant to surround the target and detect charged particles emerging from the hydrogen. The experiment was a CERN-Saclay collaboration which used the linac so as to take advantage of the time structure of the electron beam(see CERN Courier Sep 1977 and J. Bardin et al. Phys. Lett. B104 (1981) 320)

  1. Francisella tularensis LVS evades killing by human neutrophils via inhibition of the respiratory burst and phagosome escape.

    Science.gov (United States)

    McCaffrey, Ramona L; Allen, Lee-Ann H

    2006-12-01

    Francisella tularensis is a Gram-negative bacterium and the causative agent of tularemia. Recent data indicate that F. tularensis replicates inside macrophages, but its fate in other cell types, including human neutrophils, is unclear. We now show that F. tularensis live vaccine strain (LVS), opsonized with normal human serum, was rapidly ingested by neutrophils but was not eliminated. Moreover, evasion of intracellular killing can be explained, in part, by disruption of the respiratory burst. As judged by luminol-enhanced chemiluminescence and nitroblue tetrazolium staining, neutrophils infected with live F. tularensis did not generate reactive oxygen species. Confocal microscopy demonstrated that NADPH oxidase assembly was disrupted, and LVS phagosomes did not acquire gp91/p22(phox) or p47/p67(phox). At the same time, F. tularensis also impaired neutrophil activation by heterologous stimuli such as phorbol esters and opsonized zymosan particles. Later in infection, LVS escaped the phagosome, and live organisms persisted in the neutrophil cytosol for at least 12 h. To our knowledge, our data are the first demonstration of a facultative intracellular pathogen, which disrupts the oxidative burst and escapes the phagosome to evade elimination inside neutrophils, and as such, our data define a novel mechanism of virulence.

  2. Simvastatin enhances protection against Listeria monocytogenes infection in mice by counteracting Listeria-induced phagosomal escape.

    Directory of Open Access Journals (Sweden)

    Suraj P Parihar

    Full Text Available Statins are well-known cholesterol lowering drugs targeting HMG-CoA-reductase, reducing the risk of coronary disorders and hypercholesterolemia. Statins are also involved in immunomodulation, which might influence the outcome of bacterial infection. Hence, a possible effect of statin treatment on Listeriosis was explored in mice. Statin treatment prior to subsequent L. monocytogenes infection strikingly reduced bacterial burden in liver and spleen (up to 100-fold and reduced histopathological lesions. Statin-treatment in infected macrophages resulted in increased IL-12p40 and TNF-α and up to 4-fold reduced bacterial burden within 6 hours post infection, demonstrating a direct effect of statins on limiting bacterial growth in macrophages. Bacterial uptake was normal investigated in microbeads and GFP-expressing Listeria experiments by confocal microscopy. However, intracellular membrane-bound cholesterol level was decreased, as analyzed by cholesterol-dependent filipin staining and cellular lipid extraction. Mevalonate supplementation restored statin-inhibited cholesterol biosynthesis and reverted bacterial growth in Listeria monocytogenes but not in listeriolysin O (LLO-deficient Listeria. Together, these results suggest that statin pretreatment increases protection against L. monocytogenes infection by reducing membrane cholesterol in macrophages and thereby preventing effectivity of the cholesterol-dependent LLO-mediated phagosomal escape of bacteria.

  3. WASH drives early recycling from macropinosomes and phagosomes to maintain surface phagocytic receptors

    Science.gov (United States)

    Buckley, Catherine M.; Gopaldass, Navin; Bosmani, Cristina; Johnston, Simon A.; Insall, Robert H.

    2016-01-01

    Macropinocytosis is an ancient mechanism that allows cells to harvest nutrients from extracellular media, which also allows immune cells to sample antigens from their surroundings. During macropinosome formation, bulk plasma membrane is internalized with all its integral proteins. It is vital for cells to salvage these proteins before degradation, but the mechanisms for sorting them are not known. Here we describe the evolutionarily conserved recruitment of the WASH (WASP and SCAR homolog) complex to both macropinosomes and phagosomes within a minute of internalization. Using Dictyostelium, we demonstrate that WASH drives protein sorting and recycling from macropinosomes and is thus essential to maintain surface receptor levels and sustain phagocytosis. WASH functionally interacts with the retromer complex at both early and late phases of macropinosome maturation, but mediates recycling via retromer-dependent and -independent pathways. WASH mutants consequently have decreased membrane levels of integrins and other surface proteins. This study reveals an important pathway enabling cells to sustain macropinocytosis without bulk degradation of plasma membrane components. PMID:27647881

  4. A Comprehensive Subcellular Proteomic Survey of Salmonella Grown under Phagosome-Mimicking versus Standard Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Roslyn N. Brown

    2012-01-01

    Full Text Available Towards developing a systems-level pathobiological understanding of Salmonella enterica, we performed a subcellular proteomic analysis of this pathogen grown under standard laboratory and phagosome-mimicking conditions in vitro. Analysis of proteins from cytoplasmic, inner membrane, periplasmic, and outer membrane fractions yielded coverage of 25% of the theoretical proteome. Confident subcellular location could be assigned to over 1000 proteins, with good agreement between experimentally observed location and predicted/known protein properties. Comparison of protein location under the different environmental conditions provided insight into dynamic protein localization and possible moonlighting (multiple function activities. Notable examples of dynamic localization were the response regulators of two-component regulatory systems (e.g., ArcB and PhoQ. The DNA-binding protein Dps that is generally regarded as cytoplasmic was significantly enriched in the outer membrane for all growth conditions examined, suggestive of moonlighting activities. These observations imply the existence of unknown transport mechanisms and novel functions for a subset of Salmonella proteins. Overall, this work provides a catalog of experimentally verified subcellular protein locations for Salmonella and a framework for further investigations using computational modeling.

  5. Diversion of phagosome trafficking by pathogenic Rhodococcus equi depends on mycolic acid chain length.

    Science.gov (United States)

    Sydor, Tobias; von Bargen, Kristine; Hsu, Fong-Fu; Huth, Gitta; Holst, Otto; Wohlmann, Jens; Becken, Ulrike; Dykstra, Tobias; Söhl, Kristina; Lindner, Buko; Prescott, John F; Schaible, Ulrich E; Utermöhlen, Olaf; Haas, Albert

    2013-03-01

    Rhodococcus equi is a close relative of Mycobacterium spp. and a facultative intracellular pathogen which arrests phagosome maturation in macrophages before the late endocytic stage. We have screened a transposon mutant library of R. equi for mutants with decreased capability to prevent phagolysosome formation. This screen yielded a mutant in the gene for β-ketoacyl-(acyl carrier protein)-synthase A (KasA), a key enzyme of the long-chain mycolic acid synthesizing FAS-II system. The longest kasA mutant mycolic acid chains were 10 carbon units shorter than those of wild-type bacteria. Coating of non-pathogenic E. coli with purified wild-type trehalose dimycolate reduced phagolysosome formation substantially which was not the case with shorter kasA mutant-derived trehalose dimycolate. The mutant was moderately attenuated in macrophages and in a mouse infection model, but was fully cytotoxic.Whereas loss of KasA is lethal in mycobacteria, R. equi kasA mutant multiplication in broth was normal proving that long-chain mycolic acid compounds are not necessarily required for cellular integrity and viability of the bacteria that typically produce them. This study demonstrates a central role of mycolic acid chain length in diversion of trafficking by R. equi. © 2012 Blackwell Publishing Ltd.

  6. The Cell Wall Lipid PDIM Contributes to Phagosomal Escape and Host Cell Exit of Mycobacterium tuberculosis

    Science.gov (United States)

    Quigley, Jeff; Hughitt, V. Keith; Velikovsky, Carlos A.; Mariuzza, Roy A.

    2017-01-01

    ABSTRACT The cell wall of Mycobacterium tuberculosis is composed of unique lipids that are important for pathogenesis. Indeed, the first-ever genetic screen in M. tuberculosis identified genes involved in the biosynthesis and transport of the cell wall lipid PDIM (phthiocerol dimycocerosates) as crucial for the survival of M. tuberculosis in mice. Here we show evidence for a novel molecular mechanism of the PDIM-mediated virulence in M. tuberculosis. We characterized the DNA interaction and the regulon of Rv3167c, a transcriptional repressor that is involved in virulence regulation of M. tuberculosis, and discovered that it controls the PDIM operon. A loss-of-function genetic approach showed that PDIM levels directly correlate with the capacity of M. tuberculosis to escape the phagosome and induce host cell necrosis and macroautophagy. In conclusion, our study attributes a novel role of the cell wall lipid PDIM in intracellular host cell modulation, which is important for host cell exit and dissemination of M. tuberculosis. PMID:28270579

  7. Salmonella modulation of the phagosome membrane, role of SseJ.

    Science.gov (United States)

    Kolodziejek, Anna M; Miller, Samuel I

    2015-03-01

    Salmonellae have the ability to invade, persist and replicate within an intracellular phagosome termed the Salmonella-containing vacuole (SCV). Salmonellae alter lipid and protein content of the SCV membrane and manipulate cytoskeletal elements in contact with the SCV using the Salmonella pathogenicity island 1 (SPI-2) type III secretion system effectors. These modifications result in microtubular-based movement and morphological changes, which include endosomal tubulation of the SCV membrane. SseJ is a SPI-2 effector that localizes to the cytoplasmic face of the SCV and esterifies cholesterol through its glycerophospholipid : cholesterol acyltransferase activity. SseJ enzymatic activity as well as localization to the SCV are determined by binding to the small mammalian GTPase, RhoA. This review will focus on current knowledge about the role of SseJ in SCV membrane modification and will discuss how the hypothesis that a major role of SPI-2 effectors is to modify SCV protein and lipid content to promote bacterial intracellular survival.

  8. Geiger Counter Technique

    Science.gov (United States)

    1942-01-01

    is a Genco HIyvac and is backed by a single stage oil diffusion punp. The mercury well is emnloyed as a pump and mixing chamber, providing a means of...system, after first being puaped down, is filled to ovar-priees-e with Argan . re counter is then pullet off the ribber tubing a few dorps of ether are

  9. Characterization of the intracellular survival of Mycobacterium avium ssp. paratuberculosis: phagosomal pH and fusogenicity in J774 macrophages compared with other mycobacteria.

    Science.gov (United States)

    Kuehnel, M P; Goethe, R; Habermann, A; Mueller, E; Rohde, M; Griffiths, G; Valentin-Weigand, P

    2001-08-01

    The phagosomes containing viable pathogenic mycobacteria, such as Mycobacterium (M.) tuberculosis and Mycobacterium avium ssp. avium (M. avium), are known to be limited in their ability to both acidify and fuse with late (but not early) endocytic organelles. Here, we analysed the pH and fusogenicity of phagosomes containing M. avium ssp. paratuberculosis (M. ptb), the causative agent of paratuberculosis in ruminants. Using the murine J774 macrophage cell line, we compared viable and heat-killed M. ptb and, in addition, viable or dead M. avium, as well as two non-pathogenic mycobacteria, Mycobacterium smegmatis and Mycobacterium gordonae. Electron microscopic analysis revealed that M. ptb persisted intracellularly in phagosomes for up to 15 days. The phagosomes containing live M. ptb and M. avium were significantly reduced in their ability to acquire some markers for the endocytic pathway, such as internalized calcein, BSA-gold or the membrane protein Lamp 2. However, they were almost completely accessible to 70 kDa fluorescein isothiocyanate (FITC)-dextran and Lamp 1. Overall, the phagosomes containing dead pathogenic mycobacteria behaved similarly to the ones containing live non-pathogenic mycobacteria in all experiments. Using FITC-dextran in a novel fluorescence-activated cell sorting (FACS)-based method, we could also show that the bulk of endocytic compartments, including phagosomes, were only very mildly acidified to approximately pH 6.3 over at least 72 h in J774 cells infected with live M. ptb and M. avium. In contrast, J774 cells treated with heat-killed M. ptb or BSA-coated latex beads showed substantial acidification of the phagosome/endocytic compartments to a pH value of approximately 5.2. After infection with M. smegmatis and M. gordonae, acidification was initially (1-5 h after infection) inhibited, but increased after longer infection to levels similar to those with dead mycobacteria.

  10. Relationship between platelet and urinary 8-Iso-PGF2α levels in subjects with different degrees of NOX2 regulation.

    Science.gov (United States)

    Carnevale, Roberto; Iuliano, Luigi; Nocella, Cristina; Bartimoccia, Simona; Trapè, Stefano; Russo, Roberta; Gentile, Maria Cristina; Cangemi, Roberto; Loffredo, Lorenzo; Pignatelli, Pasquale; Violi, Francesco

    2013-06-14

    Urinary 8-iso-PGF2α, a marker of oxidative stress, is influenced by the activation of NOX2. It is unclear if platelets 8-iso-PGF2α contribute to urinary 8-iso-PGF2α. In a cross-sectional study, platelet, urinary, and serum 8-iso-PGF2α were determined in subjects with downregulation (X-linked chronic granulomatous disease [X-CGD], n=25) and upregulation (type II diabetic patients [T2D], n=121) of NOX2 and 153 controls matched for sex and age. In diabetic patients (n=18), the above variables were repeated before and after 7 days treatment with 100 mg/day aspirin or 100 mg/day aspirin plus 40 mg/day atorvastatin. In vitro study was performed to see the contribution of blood cells to serum 8-iso-PGF2α. Compared with controls, X-CGD patients had lower platelet, serum, and urinary 8-iso-PGF2α values; conversely, diabetic patients had higher values of 8-iso-PGF2α compared with controls. Urinary 8-iso-PGF2α significantly correlated with both platelet and serum 8-iso-PGF2α in the 2 cohorts. A parallel increase of platelet, serum, and urinary 8-iso-PGF2α by aspirin and a parallel decrease by aspirin plus atorvastatin were detected in the interventional study. In vitro study demonstrated that platelets contribute to 37% of serum 8-iso-PGF2α and that only 13% of it is of extravascular origin. The study suggests that NOX2 contributes to the formation of 8-iso-PGF2α in both platelets and urine. The direct correlation between platelet and urinary 8-iso-PGF2α suggests that, at least partly, urinary 8-iso-PGF2α reflects platelet 8-iso-PGF2α production. Analysis of serum 8-iso-PGF2α may represent a novel tool to investigate the production of 8-iso-PGF2α by blood cells including platelets. URL: ClinicalTrials.gov. Unique Identifier: NCT01250340.

  11. Relationship Between Platelet and Urinary 8‐Iso‐PGF2α Levels in Subjects With Different Degrees of NOX2 Regulation

    Science.gov (United States)

    Carnevale, Roberto; Iuliano, Luigi; Nocella, Cristina; Bartimoccia, Simona; Trapè, Stefano; Russo, Roberta; Gentile, Maria Cristina; Cangemi, Roberto; Loffredo, Lorenzo; Pignatelli, Pasquale; Violi, Francesco

    2013-01-01

    Background Urinary 8‐iso‐PGF2α, a marker of oxidative stress, is influenced by the activation of NOX2. It is unclear if platelets 8‐iso‐PGF2α contribute to urinary 8‐iso‐PGF2α. Methods and Results In a cross‐sectional study, platelet, urinary, and serum 8‐iso‐PGF2α were determined in subjects with downregulation (X‐linked chronic granulomatous disease [X‐CGD], n=25) and upregulation (type II diabetic patients [T2D], n=121) of NOX2 and 153 controls matched for sex and age. In diabetic patients (n=18), the above variables were repeated before and after 7 days treatment with 100 mg/day aspirin or 100 mg/day aspirin plus 40 mg/day atorvastatin. In vitro study was performed to see the contribution of blood cells to serum 8‐iso‐PGF2α. Compared with controls, X‐CGD patients had lower platelet, serum, and urinary 8‐iso‐PGF2α values; conversely, diabetic patients had higher values of 8‐iso‐PGF2α compared with controls. Urinary 8‐iso‐PGF2α significantly correlated with both platelet and serum 8‐iso‐PGF2α in the 2 cohorts. A parallel increase of platelet, serum, and urinary 8‐iso‐PGF2α by aspirin and a parallel decrease by aspirin plus atorvastatin were detected in the interventional study. In vitro study demonstrated that platelets contribute to 37% of serum 8‐iso‐PGF2α and that only 13% of it is of extravascular origin. Conclusions The study suggests that NOX2 contributes to the formation of 8‐iso‐PGF2α in both platelets and urine. The direct correlation between platelet and urinary 8‐iso‐PGF2α suggests that, at least partly, urinary 8‐iso‐PGF2α reflects platelet 8‐iso‐PGF2α production. Analysis of serum 8‐iso‐PGF2α may represent a novel tool to investigate the production of 8‐iso‐PGF2α by blood cells including platelets. Clinical Trial Registration URL: ClinicalTrials.gov. Unique Identifier: NCT01250340. PMID:23770972

  12. Countering rumors about contraceptives.

    Science.gov (United States)

    Del Rosario, M L

    1976-01-01

    Rumors are among the serious problems of the National Population Program today. The principles related to the origin of rumors, who starts rumors pertaining to family planning, and how they spread are outlined. The basic approach in countering rumors for the pill and IUD is diagrammed so that each potential rumor is countered by a medical or nonmedical/technical explanation. Strategies used by information-education-communication programs to prevent rumors such as the small group discussion, selection and training of motivators, and use of mass media are discussed. Rumors about family planning are counteracted not with the use of elaborate techniques but with clear and fairly simple reassurances supported by medical evidence and case histories.

  13. Low dose dextromethorphan attenuates moderate experimental autoimmune encephalomyelitis by inhibiting NOX2 and reducing peripheral immune cells infiltration in the spinal cord

    Science.gov (United States)

    Chechneva, Olga V.; Mayrhofer, Florian; Daugherty, Daniel J.; Pleasure, David E.; Hong, Jau-Shyong; Deng, Wenbin

    2011-01-01

    Dextromethorphan (DM) is a dextrorotary morphinan and a widely used component of cough medicine. Relatively high doses of DM in combination with quinidine are used for the treatment of mood disorders for patients with multiple sclerosis (MS). However, at lower doses, morphinans exert anti-inflammatory activities through the inhibition of NOX2-dependent superoxide production in activated microglia. Here we investigated the effects of high (10 mg/kg, i.p., “DM-10”) and low (0.1 mg/kg, i.p., “DM-0.1”) doses of DM on the development and progression of mouse experimental autoimmune encephalomyelitis (EAE), an animal model of MS. We found no protection by high dose DM treatment. Interestingly, a minor late attenuation by low dose DM treatment was seen in severe EAE that was characterized by a chronic disease course and a massive spinal cord infiltration of CD45+ cells including T-lymphocytes, macrophages and neutrophils. Furthermore, in a less severe form of EAE, where lower levels of CD4+ and CD8+ T-cells, Iba1+ microglia/macrophages and no significant infiltration of neutrophils were seen in the spinal cord, the treatment with DM-0.1 was remarkably more beneficial. The effect was the most significant at the peak of disease and was associated with an inhibition of NOX2 expression and a decrease in infiltration of monocytes and lymphocytes into the spinal cord. In addition, chronic treatment with low dose DM resulted in decreased demyelination and reduced axonal loss in the lumbar spinal cord. Our study is the first report to show that low dose DM is effective in treating EAE of moderate severity. Our findings reveal that low dose morphinan DM treatment may represent a new promising protective strategy for treating MS. PMID:21704706

  14. Electromagnetic shower counter

    CERN Multimedia

    1974-01-01

    The octogonal block of lead glass is observed by eight photomultiplier tubes. Four or five such counters, arranged in succession, are used on each arm of the bispectrometer in order to detect heavy particles of the same family as those recently observed at Brookhaven and SLAC. They provide a means of identifying electrons. The arrangement of eight lateral photomultiplier tubes offers an efficient means of collecting the photons produced in the showers and determining, with a high resolution, the energy of the incident electrons. The total width at half-height is less than 6.9% for electrons having an energy of 1 GeV.

  15. The human fungal pathogen Cryptococcus neoformans escapes macrophages by a phagosome emptying mechanism that is inhibited by Arp2/3 complex-mediated actin polymerisation.

    Directory of Open Access Journals (Sweden)

    Simon A Johnston

    Full Text Available The lysis of infected cells by disease-causing microorganisms is an efficient but risky strategy for disseminated infection, as it exposes the pathogen to the full repertoire of the host's immune system. Cryptococcus neoformans is a widespread fungal pathogen that causes a fatal meningitis in HIV and other immunocompromised patients. Following intracellular growth, cryptococci are able to escape their host cells by a non-lytic expulsive mechanism that may contribute to the invasion of the central nervous system. Non-lytic escape is also exhibited by some bacterial pathogens and is likely to facilitate long-term avoidance of the host immune system during latency. Here we show that phagosomes containing intracellular cryptococci undergo repeated cycles of actin polymerisation. These actin 'flashes' occur in both murine and human macrophages and are dependent on classical WASP-Arp2/3 complex mediated actin filament nucleation. Three dimensional confocal imaging time lapse revealed that such flashes are highly dynamic actin cages that form around the phagosome. Using fluorescent dextran as a phagosome membrane integrity probe, we find that the non-lytic expulsion of Cryptococcus occurs through fusion of the phagosome and plasma membranes and that, prior to expulsion, 95% of phagosomes become permeabilised, an event that is immediately followed by an actin flash. By using pharmacological agents to modulate both actin dynamics and upstream signalling events, we show that flash occurrence is inversely related to cryptococcal expulsion, suggesting that flashes may act to temporarily inhibit expulsion from infected phagocytes. In conclusion, our data reveal the existence of a novel actin-dependent process on phagosomes containing cryptococci that acts as a potential block to expulsion of Cryptococcus and may have significant implications for the dissemination of, and CNS invasion by, this organism.

  16. Quantum counter automata

    CERN Document Server

    Say, A C Cem

    2011-01-01

    The question of whether quantum real-time one-counter automata (rtQ1CAs) can outperform their probabilistic counterparts has been open for more than a decade. We provide an affirmative answer to this question, by demonstrating a non-context-free language that can be recognized with perfect soundness by a rtQ1CA. This is the first demonstration of the superiority of a quantum model to the corresponding classical one in the real-time case with an error bound less than 1. We also introduce a generalization of the rtQ1CA, the quantum one-way one-counter automaton (1Q1CA), and show that they too are superior to the corresponding family of probabilistic machines. For this purpose, we provide general definitions of these models that reflect the modern approach to the definition of quantum finite automata, and point out some problems with previous results. We identify several remaining open problems.

  17. A novel role for Stat1 in phagosome acidification and natural host resistance to intracellular infection by Leishmania major.

    Directory of Open Access Journals (Sweden)

    Gerald F Späth

    2009-04-01

    Full Text Available Intracellular parasites of the genus Leishmania generate severe diseases in humans, which are associated with a failure of the infected host to induce a protective interferon gamma (IFNgamma-mediated immune response. We tested the role of the JAK/STAT1 signaling pathway in Leishmania pathogenesis by utilizing knockout mice lacking the signal transducer and activator of transcription 1 (Stat1 and derived macrophages. Unexpectedly, infection of Stat1-deficient macrophages in vitro with promastigotes from Leishmania major and attenuated LPG1 knockout mutants (lpg(- specifically lacking lipophosphoglycan (LPG resulted in a twofold increased intracellular growth, which was independent of IFNgamma and associated with a substantial increase in phagosomal pH. Phagosomes in Stat1-/- macrophages showed normal maturation as judged by the accumulation of the lysosomal marker protein rab7, and provided normal vATPase activity, but were defective in the anion conductive pathway required for full vesicular acidification. Our results suggest a role of acidic pH in the control of intracellular Leishmania growth early during infection and identify for the first time an unexpected role of Stat1 in natural anti-microbial resistance independent from its function as IFNgamma-induced signal transducer. This novel Stat1 function may have important implications to studies of other pathogens, as the acidic phagolysosomal pH plays an important role in antigen processing and the uncoating process of many viruses.

  18. Counter-Rotating Accretion Discs

    OpenAIRE

    Dyda, Sergei; Lovelace, Richard V. E.; Ustyugova, Galina V.; Romanova, Marina M.; Koldoba, Alexander V.

    2014-01-01

    Counter-rotating discs can arise from the accretion of a counter-rotating gas cloud onto the surface of an existing co-rotating disc or from the counter-rotating gas moving radially inward to the outer edge of an existing disc. At the interface, the two components mix to produce gas or plasma with zero net angular momentum which tends to free-fall towards the disc center. We discuss high-resolution axisymmetric hydrodynamic simulations of a viscous counter-rotating disc for cases where the tw...

  19. Space and power efficient hybrid counters array

    Science.gov (United States)

    Gara, Alan G.; Salapura, Valentina

    2009-05-12

    A hybrid counter array device for counting events. The hybrid counter array includes a first counter portion comprising N counter devices, each counter device for receiving signals representing occurrences of events from an event source and providing a first count value corresponding to a lower order bits of the hybrid counter array. The hybrid counter array includes a second counter portion comprising a memory array device having N addressable memory locations in correspondence with the N counter devices, each addressable memory location for storing a second count value representing higher order bits of the hybrid counter array. A control device monitors each of the N counter devices of the first counter portion and initiates updating a value of a corresponding second count value stored at the corresponding addressable memory location in the second counter portion. Thus, a combination of the first and second count values provide an instantaneous measure of number of events received.

  20. The microstrip proportional counter

    Science.gov (United States)

    Ramsey, B. D.

    1992-01-01

    Microstrip detectors in which the usual discrete anode and cathode wires are replaced by conducting strips on an insulating or partially insulating substrate are fabricated using integrated circuit-type photolithographic techniques and hence offer very high spatial accuracy and uniformity, together with the capability of producing extremely fine electrode structures. Microstrip proportional counters have now been variously reported having an energy resolution of better than 11 percent FWHM at 5.9 keV. They have been fabricated with anode bars down to 2 microns and on a variety of substrate materials including thin films which can be molded to different shapes. This review will examine the development of the microstrip detector with emphasis on the qualities which make this detector particularly interesting for use in astronomy.

  1. Counter-Learning under Oppression

    Science.gov (United States)

    Kucukaydin, Ilhan

    2010-01-01

    This qualitative study utilized the method of narrative analysis to explore the counter-learning process of an oppressed Kurdish woman from Turkey. Critical constructivism was utilized to analyze counter-learning; Frankfurt School-based Marcusian critical theory was used to analyze the sociopolitical context and its impact on the oppressed. Key…

  2. Mycobacterium tuberculosis WhiB3 Responds to Vacuolar pH-induced Changes in Mycothiol Redox Potential to Modulate Phagosomal Maturation and Virulence.

    Science.gov (United States)

    Mehta, Mansi; Rajmani, Raju S; Singh, Amit

    2016-02-05

    The ability of Mycobacterium tuberculosis to resist intraphagosomal stresses, such as oxygen radicals and low pH, is critical for its persistence. Here, we show that a cytoplasmic redox sensor, WhiB3, and the major M. tuberculosis thiol, mycothiol (MSH), are required to resist acidic stress during infection. WhiB3 regulates the expression of genes involved in lipid anabolism, secretion, and redox metabolism, in response to acidic pH. Furthermore, inactivation of the MSH pathway subverted the expression of whiB3 along with other pH-specific genes in M. tuberculosis. Using a genetic biosensor of mycothiol redox potential (EMSH), we demonstrated that a modest decrease in phagosomal pH is sufficient to generate redox heterogeneity in EMSH of the M. tuberculosis population in a WhiB3-dependent manner. Data indicate that M. tuberculosis needs low pH as a signal to alter cytoplasmic EMSH, which activates WhiB3-mediated gene expression and acid resistance. Importantly, WhiB3 regulates intraphagosomal pH by down-regulating the expression of innate immune genes and blocking phagosomal maturation. We show that this block in phagosomal maturation is in part due to WhiB3-dependent production of polyketide lipids. Consistent with these observations, MtbΔwhiB3 displayed intramacrophage survival defect, which can be rescued bypharmacological inhibition of phagosomal acidification. Last, MtbΔwhiB3 displayed marked attenuation in the lungs of guinea pigs. Altogether, our study revealed an intimate link between vacuolar acidification, redox physiology, and virulence in M. tuberculosis and discovered WhiB3 as crucial mediator of phagosomal maturation arrest and acid resistance in M. tuberculosis.

  3. Counter-driver shock tube

    Science.gov (United States)

    Tamba, T.; Nguyen, T. M.; Takeya, K.; Harasaki, T.; Iwakawa, A.; Sasoh, A.

    2015-11-01

    A "counter-driver" shock tube was developed. In this device, two counter drivers are actuated with an appropriate delay time to generate the interaction between a shock wave and a flow in the opposite direction which is induced by another shock wave. The conditions for the counter drivers can be set independently. Each driver is activated by a separate electrically controlled diaphragm rupture device, in which a pneumatic piston drives a rupture needle with a temporal jitter of better than 1.1 ms. Operation demonstrations were conducted to evaluate the practical performance.

  4. Global triplet potential energy surfaces for the N2(X(1)Σ) + O((3)P) → NO(X(2)Π) + N((4)S) reaction.

    Science.gov (United States)

    Lin, Wei; Varga, Zoltan; Song, Guoliang; Paukku, Yuliya; Truhlar, Donald G

    2016-01-14

    This work presents two global triplet potential energy surfaces (PESs) for the high-energy reaction N2(X(1)Σ) + O((3)P) → NO(X(2)Π) + N((4)S)-in particular, for the lowest energy (3)A' and (3)A″ PESs. In order to obtain the energies needed for fitting analytic surfaces, we carried out multireference configuration interaction (MRCI) calculations based on wave functions obtained from state-averaged complete active space self-consistent field calculations for 2280 geometries for the three lowest (3)A″ states and for 2298 geometries for the three lowest (3)A' states. The lowest-energy (3)A' and (3)A″ states at each of these geometries were then improved by applying the dynamically scaled external correlation (DSEC) method to all MRCI points, and the resulting DSEC energies were used for construction of the ground-state PES for each symmetry. The many-body component of the DSEC energies for the three-dimensional (3)A' and (3)A″ PESs was then least-squares fitted in terms of permutationally invariant polynomials in mixed exponential-Gaussian bond order variables. The global and local minima as well as the transition structures of both the (3)A' and the (3)A″ analytic PES were explored. In agreement with previous work, we find that the reverse reaction is barrierless on the (3)A″ surface along the minimum energy pathway. However, we have explored several new local minima and transition structures on the (3)A' PES. Furthermore, based on the newly found minima and transition structures, two independent reaction mechanisms have been illustrated for the reaction path on the (3)A' PES. The analytic surfaces may be used for dynamics calculations of electronically adiabatic reactive scattering and energy transfer.

  5. Over-the-Counter Medicines

    Science.gov (United States)

    Over-the-counter (OTC) medicines are drugs you can buy without a prescription. Some OTC medicines relieve aches, pains ... Others help manage recurring problems, like migraines. In the United States, the Food and Drug Administration decides ...

  6. The anti-oxidative role of micro-vesicles derived from human Wharton-Jelly mesenchymal stromal cells through NOX2/gp91(phox suppression in alleviating renal ischemia-reperfusion injury in rats.

    Directory of Open Access Journals (Sweden)

    Guangyuan Zhang

    Full Text Available Oxidative stress is known as one of the main contributors in renal ischemia/reperfusion injury (IRI. Here we hypothesized that Micro-vesicles (MVs derived from human Wharton Jelly mesenchymal stromal cells (hWJMSCs could protect kidney against IRI through mitigating oxidative stress. MVs isolated from hWJMSCs conditioned medium were injected intravenously in rats immediately after unilateral kidney ischemia for 60 min. The animals were sacrificed at 24 h, 48 h and 2 weeks respectively after reperfusion. Our results show that the expression of NOX2 and reactive oxygen species (ROS in injured kidney tissues was declined and the oxidative stress was alleviated in MVs group at 24 h and 48 h in parallel with the reduced apoptosis and enhanced proliferation of cells. IRI-initiated fibrosis was abrogated by MVs coincident with renal function amelioration at 2 weeks. NOX2 was also found down-regulated by MVs both in human umbilical vein endothelial cells (HUVEC and NRK-52E cell line under hypoxia injury model in vitro. In conclusion, a single administration of hWJMSC-MVs might protect the kidney by alleviation of the oxidative stress in the early stage of kidney IRI through suppressing NOX2 expression. Moreover, it could reduce the fibrosis and improved renal function.

  7. The consequences of Israel's counter terrorism policy

    OpenAIRE

    Jansen, Pia Therese

    2008-01-01

    The main focus of this thesis is to examine Israel's counter terrorism methods and their consequences and to debate the effectiveness of Israel's counter terrorism policy. By stimulating a debate on these issues it is possible to identify a more effective counter terrorism policy. In order to examine Israel's counter terrorism methods, their consequences and effectiveness, it is necessary to first explore the overall concepts of terrorism and counter terrorism. Then, because...

  8. Disruption of the phagosomal membrane and egress of Legionella pneumophila into the cytoplasm during the last stages of intracellular infection of macrophages and Acanthamoeba polyphaga.

    Science.gov (United States)

    Molmeret, Maëlle; Bitar, Dina M; Han, Lihui; Kwaik, Yousef Abu

    2004-07-01

    Although the early stages of intracellular infection by Legionella pneumophila are well established at the ultrastructural level, a detailed ultrastructural analysis of late stages of intracellular replication has never been done. Here we show that the membrane of the L. pneumophila-containing phagosome (LCP) is intact for up to 8 h postinfection of macrophages and Acanthamoeba polyphaga. At 12 h, 71 and 74% of the LCPs are disrupted within macrophages and A. polyphaga, respectively, while the plasma membrane remains intact. At 18 and 24 h postinfection, cytoplasmic elements such as mitochondria, lysosomes, vesicles, and amorphous material are dispersed among the bacteria and these bacteria are considered cytoplasmic. At 18 h, 77% of infected macrophages and 32% of infected A. polyphaga amoebae harbor cytoplasmic bacteria. At 24 h, 99 and 78% of infected macrophages and amoebae, respectively, contain cytoplasmic bacteria. On the basis of lysosomal acid phosphatase staining of infected macrophages and A. polyphaga, the lysosomal enzyme is present among the bacteria when host vesicles are dispersed among bacteria. Our data indicate that bacterial replication proceeds despite physical disruption of the phagosomal membrane. We also show that an lspG mutant that is defective in the type II secretion system and therefore does not secrete the hydrolytic enzymes metalloprotease, p-nitrophenol phosphorylcholine hydrolase, lipase, phospholipase A, and lysophospholipase A is as efficient as the wild-type strain in disruption of the LCP. Therefore, L. pneumophila disrupts the phagosomal membrane and becomes cytoplasmic at the last stages of infection in both macrophages and A. polyphaga. Lysosomal elements, mitochondria, cytoplasmic vesicles, and amorphous material are all dispersed among the bacteria, after phagosomal disruption, within both human macrophages and A. polyphaga. The disruption of the LCP is independent of the hydrolytic enzymes exported by the type II secretion

  9. Turbulent mixing condensation nucleus counter

    Science.gov (United States)

    Mavliev, Rashid

    The construction and operating principles of the Turbulent Mixing Condensation Nucleus Counter (TM CNC) are described. Estimations based on the semiempirical theory of turbulent jets and the classical theory of nucleation and growth show the possibility of detecting particles as small as 2.5 nm without the interference of homogeneous nucleation. This conclusion was confirmed experimentally during the International Workshop on Intercomparison of Condensation Nuclei and Aerosol Particle Counters (Vienna, Austria). Number concentration, measured by the Turbulent Mixing CNC and other participating instruments, is found to be essentially equal.

  10. Countering 21st Century Threats

    DEFF Research Database (Denmark)

    Scharling Pedersen, Peter; Pillai, Chad M.; Hun, Lee Jae

    2015-01-01

    ), Counter-Terrorism (CT), and Security and Stability Operations (SSO). • Establishing a construct that allows a strategic Whole-of-Government capacity for operations coordinated by joint interagency task forces. • Continue to developing the Global SOF network. • Increased intelligence sharing in areas...... to be addressed in order to successfully conduct IW. As result of researching the issues associated with developing a JIIM approach to IW, the paper makes the following recommendations: • Establishing universally accepted concepts and doctrines for IW, UW, Foreign Internal Defense (FID), Counter Insurgency (COIN...

  11. Counter-Rotating Accretion Discs

    CERN Document Server

    Dyda, Sergei; Ustyugova, Galina V; Romanova, Marina M; Koldoba, Alexander V

    2014-01-01

    Counter-rotating discs can arise from the accretion of a counter-rotating gas cloud onto the surface of an existing co-rotating disc or from the counter-rotating gas moving radially inward to the outer edge of an existing disc. At the interface, the two components mix to produce gas or plasma with zero net angular momentum which tends to free-fall towards the disc center. We discuss high-resolution axisymmetric hydrodynamic simulations of a viscous counter-rotating disc for cases where the two components are vertically separated and radially separated. The viscosity is described by an isotropic $\\alpha-$viscosity including all terms in the viscous stress tensor. For the vertically separated components a shear layer forms between them. The middle of this layer free-falls to the disk center. The accretion rates are increased by factors $\\sim 10^2-10^4$ over that of a conventional disc rotating in one direction with the same viscosity. The vertical width of the shear layer and the accretion rate are strongly dep...

  12. The Eros of Counter Education

    Science.gov (United States)

    Luzon, Pinhas

    2016-01-01

    Erotic Counter Education (ECE) is the educational position of the late Ilan Gur-Ze'ev. In ECE Gur-Ze'ev combines two opposing positions in the philosophy of education, one teleological and anti-utopian, the other teleological and utopian. In light of this unique combination, I ask what mediates between these two poles and suggest that the answer…

  13. Basic Research Needs for Countering Terrorism

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, W.; Michalske, T.; Trewhella, J.; Makowski, L.; Swanson, B.; Colson, S.; Hazen, T.; Roberto, F.; Franz, D.; Resnick, G.; Jacobson, S.; Valdez, J.; Gourley, P.; Tadros, M.; Sigman, M.; Sailor, M.; Ramsey, M.; Smith, B.; Shea, K.; Hrbek, J.; Rodacy, P.; Tevault, D.; Edelstein, N.; Beitz, J.; Burns, C.; Choppin, G.; Clark, S.; Dietz, M.; Rogers, R.; Traina, S.; Baldwin, D.; Thurnauer, M.; Hall, G.; Newman, L.; Miller, D.; Kung, H.; Parkin, D.; Shuh, D.; Shaw, H.; Terminello, L.; Meisel, D.; Blake, D.; Buchanan, M.; Roberto, J.; Colson, S.; Carling, R.; Samara, G.; Sasaki, D.; Pianetta, P.; Faison, B.; Thomassen, D.; Fryberger, T.; Kiernan, G.; Kreisler, M.; Morgan, L.; Hicks, J.; Dehmer, J.; Kerr, L.; Smith, B.; Mays, J.; Clark, S.

    2002-03-01

    To identify connections between technology needs for countering terrorism and underlying science issues and to recommend investment strategies to increase the impact of basic research on efforts to counter terrorism.

  14. Counter-discourse in Zimbabwean literature

    NARCIS (Netherlands)

    Mangena, Tendai

    2015-01-01

    Counter-Discourse in Zimbabwean Literature is a study of specific aspects of counter-discursive Zimbabwean narratives in English. In discussing the selected texts, my thesis is based on Terdiman’s (1989) the postcolonial concept of counter-discourse. In Zimbabwean literature challenges to a dominant

  15. Lossy Counter Machines Decidability Cheat Sheet

    Science.gov (United States)

    Schnoebelen, Philippe

    Lossy counter machines (LCM's) are a variant of Minsky counter machines based on weak (or unreliable) counters in the sense that they can decrease nondeterministically and without notification. This model, introduced by R. Mayr [TCS 297:337-354 (2003)], is not yet very well known, even though it has already proven useful for establishing hardness results.

  16. Science Experimenter: Experimenting with a Geiger Counter.

    Science.gov (United States)

    Mims, Forrest M., III

    1992-01-01

    Describes the use of geiger counters for scientific investigations and experiments. Presents information about background radiation, its sources and detection. Describes how geiger counters work and other methods of radiation detection. Provides purchasing information for geiger counters, related computer software and equipment. (MCO)

  17. Counter-discourse in Zimbabwean literature

    NARCIS (Netherlands)

    Mangena, Tendai

    2015-01-01

    Counter-Discourse in Zimbabwean Literature is a study of specific aspects of counter-discursive Zimbabwean narratives in English. In discussing the selected texts, my thesis is based on Terdiman’s (1989) the postcolonial concept of counter-discourse. In Zimbabwean literature challenges to a dominant

  18. Counter-Rotation in Disk Galaxies

    CERN Document Server

    Corsini, E M

    2014-01-01

    Counter-rotating galaxies host two components rotating in opposite directions with respect to each other. The kinematic and morphological properties of lenticulars and spirals hosting counter-rotating components are reviewed. Statistics of the counter-rotating galaxies and analysis of their stellar populations provide constraints on the formation scenarios which include both environmental and internal processes.

  19. The magnesium inhibition and arrested phagosome hypotheses: new perspectives on the evolution and ecology of Symbiodinium symbioses.

    Science.gov (United States)

    Malcolm, Hill; April, Hill

    2012-11-01

    Zooxanthella symbioses are arguably the most important ecological interaction on coral reefs because they energetically subsidize the entire community, and enhance the calcification process that provides structure for all other organisms. While we have developed a detailed understanding of the diversity among and within the Symbiodinium clades, we currently lack a mechanistic explanation for which factors favoured zooxanthella invasion of the intracellular habitat in heterotrophic hosts, and for what molecular mechanisms permit residence within the cell. We propose two hypotheses that explain important evolutionary and ecological features of zooxanthella symbioses. The magnesium inhibition hypothesis (MIH) states that increases in the Mg/Ca ratio in sea water that occurred over the last 100 million years created a situation where Mg(2+) inhibited Ca(2+) transport to zooxanthellae. The MIH predicts, among other things, that the intracellular niche was invaded as a response to this abiotic stressor. The arrested phagosome hypothesis (APH) states that Symbiodinium spp. mimic host cell endosomal digestive machinery via the symbiosome to appear like digesting prey through perpetual release of zooxanthella-derived compounds. The APH represents a subtle but important distinction from previous hypotheses regarding interactions between symbiont and host at the cellular level. The APH predicts that symbionts tune rates of material release to match expectations of host cellular machinery. An outcome of the APH is that intra-host residence time becomes a vital parameter to consider. Both hypotheses shift control of the symbiosis away from the host, and instead focus attention on the niche requirements of Symbiodinium spp. © 2012 The Authors. Biological Reviews © 2012 Cambridge Philosophical Society.

  20. Counter support for WA35

    CERN Multimedia

    1977-01-01

    This assembly was equipped with 78 counters, each consisting of a lucite cone, to produce Cerenkov light, and a CsI scintillator plate of 3 mm thickness glued on the face of the cone. The experiment WA35 was set-up in the s1 beam (West Hall) by the Darmstadt-Heidelberg-Virginia-Warsaw Collaboration to measure angular distributions and multiplicities of pions and recoil protons produced by hadrons interacting in nuclei. (See Annual Report 1976 p. 39)

  1. Science role in countering terrorism

    Science.gov (United States)

    Showstack, Randy

    Geoscience expertise figures as a component of a new report on harnessing the U.S. science and technology community in the fight against terrorism.The National Research Council report, "Making the Nation Safer: The Role of Science and Technology in Countering Terrorism," proposes research agendas in a number of areas perceived to be vulnerable to terrorism. These areas include nuclear and radiological threats, toxic chemicals and explosive materials, information technology, energy systems, and cities and fixed infrastructure.

  2. Phagosomal Acidification Prevents Macrophage Inflammatory Cytokine Production to Malaria, and Dendritic Cells Are the Major Source at the Early Stages of Infection: IMPLICATION FOR MALARIA PROTECTIVE IMMUNITY DEVELOPMENT.

    Science.gov (United States)

    Wu, Xianzhu; Gowda, Nagaraj M; Gowda, D Channe

    2015-09-18

    Inflammatory cytokines produced at the early stages of malaria infection contribute to shaping protective immunity and pathophysiology. To gain mechanistic insight into these processes, it is important to understand the cellular origin of cytokines because both cytokine input and cytokine-producing cells play key roles. Here, we determined cytokine responses by monocytes, macrophages, and dendritic cells (DCs) to purified Plasmodium falciparum and Plasmodium berghei ANKA, and by spleen macrophages and DCs from Plasmodium yoelii 17NXL-infected and P. berghei ANKA-infected mice. The results demonstrate that monocytes and macrophages do not produce inflammatory cytokines to malaria parasites and that DCs are the primary source early in infection, and DC subsets differentially produce cytokines. Importantly, blocking of phagosomal acidification by inhibiting vacuolar-type H(+)-ATPase enabled macrophages to elicit cytokine responses. Because cytokine responses to malaria parasites are mediated primarily through endosomal Toll-like receptors, our data indicate that the inability of macrophages to produce cytokines is due to the phagosomal acidification that disrupts endosomal ligand-receptor engagement. Macrophages efficiently produced cytokines to LPS upon simultaneously internalizing parasites and to heat-killed Escherichia coli, demonstrating that phagosomal acidification affects endosomal receptor-mediated, but not cell surface receptor-mediated, recognition of Toll-like receptor agonists. Enabling monocytes/macrophages to elicit immune responses to parasites by blocking endosomal acidification can be a novel strategy for the effective development of protective immunity to malaria. The results have important implications for enhancing the efficacy of a whole parasite-based malaria vaccine and for designing strategies for the development of protective immunity to pathogens that induce immune responses primarily through endosomal receptors.

  3. The transparent microstrip gas counter

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroyuki, E-mail: leo@q.t.u-tokyo.ac.j [University of Tokyo, Tokyo 113-8656 (Japan); Fujita, Kaoru; Fujiwara, Takeshi [University of Tokyo, Tokyo 113-8656 (Japan); Niko, Hisako; Guerard, Bruno [Institute of Max von Laue and Paul Langevin, BP 156, 38042 Grenoble, Cedex 9 (France); Fraga, Francisco [Departamento de Fisica, LIP-Coimbra, Universidade de Coimbra, 3000 Coimbra (Portugal); Iyomoto, Naoko [University of Tokyo, Tokyo 113-8656 (Japan)

    2010-11-01

    Conventional MSGCs are made of metal electrodes that might absorb or reflect optical photons. If the electrodes are made of transparent material like ITO, we could take advantage of optical readout. A gas scintillation proportional counter made of ITO MSGC is fabricated and tested where both optical and charge signals are obtained. We have selected a multi-grid structure that can avoid charge-up problem with normal transparent glass substrate. Test results with Ar and CF{sub 4} gas mixture showed a stable gas gain of {approx}2800 and {approx}110 optical photons for 6 keV X-rays. Position sensing with PSPMT has successfully been demonstrated.

  4. COUNTER-TERRORISM IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Jordan Sebastian Meliala

    2015-04-01

    Full Text Available Since the incident of World Trade Center (WTC in USA, Indonesia has become an easy target for the next terrorism. Counterterrorist campaigns can be undertaken by military and paramilitary forces. Counterterrorism refers to proactive policies that specifically seek to eliminate terrorist environments and groups, Regardless of which policy is selected, the ultimate goal of counterterrorism is clear: to save lives by proactively preventing or decreasing the number of terrorist attacks. But, so far the Government of Indonesia is only able to capture the terrorists but is unable to eradicate terrorism. Therefore, the government of Indonesia still needs a comprehensive ways to counter terrorism in Indonesia

  5. Condensation Particle Counter Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Kuang, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-01

    The Model 3772 CPC is a compact, rugged, and full-featured instrument that detects airborne particles down to 10 nm in diameter, at an aerosol flow rate of 1.0 lpm, over a concentration range from 0 to 1x104 #/cc. This CPC is ideally suited for applications without high concentration measurements, such as basic aerosol research, filter and air-cleaner testing, particle counter calibrations, environmental monitoring, mobile aerosol studies, particle shedding and component testing, and atmospheric and climate studies.

  6. Transcriptomic analysis of the head kidney of Topmouth culter (Culter alburnus) infected with Flavobacterium columnare with an emphasis on phagosome pathway.

    Science.gov (United States)

    Zhao, Lijuan; Tu, Jiagang; Zhang, Yulei; Wang, Jinfu; Yang, Ling; Wang, Weimin; Wu, Zaohe; Meng, Qinglei; Lin, Li

    2016-10-01

    Flavobacterium columnare (FC) has caused worldwide fish columnaris disease with high mortality and great economic losses in cultured fish, including Topmouth culter (Culter alburnus). However, the knowledge about the host factors involved in FC infection is little known. In this study, the transcriptomic profiles of the head kidney from Topmouth culter with or without FC infection were obtained using HiSeq™ 2500 (Illumina). Totally 79,641 unigenes with high quality were obtained. Among them, 4037 differently expressed genes, including 1217 up-regulated and 2820 down-regulated genes, were identified and enriched using databases of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The differently expressed genes were mainly associated with pathways such as immune response, carbohydrate metabolism, amino acid metabolism, and lipid metabolism. Since phagocytosis is a central mechanism of innate immune response by host cells to defense against infectious agents, genes related to the phagosome pathway were scrutinized and 9 differently expressed phagosome-related genes were identified including 3 up-regulated and 6 down-regulated genes. Five of them were further validated by quantitative real-time polymerase chain reaction (qRT-PCR). This transcriptomic analysis of host genes in response to FC infection provides data towards understanding the infection mechanisms and will shed a new light on the prevention of columnaris.

  7. On generating counter-rotating streamwise vortices

    KAUST Repository

    Winoto, S H

    2015-09-23

    Counter-rotating streamwise vortices are known to enhance the heat transfer rate from a surface and also to improve the aerodynamic performance of an aerofoil. In this paper, some methods to generate such counter-rotating vortices using different methods or physical conditions will be briefly considered and discussed.

  8. Counter traction makes endoscopic submucosal dissection easier.

    Science.gov (United States)

    Oyama, Tsuneo

    2012-11-01

    Poor counter traction and poor field of vision make endoscopic submucosal dissection (ESD) difficult. Good counter traction allows dissections to be performed more quickly and safely. Position change, which utilizes gravity, is the simplest method to create a clear field of vision. It is useful especially for esophageal and colon ESD. The second easiest method is clip with line method. Counter traction made by clip with line accomplishes the creation of a clear field of vision and suitable counter traction thereby making ESD more efficient and safe. The author published this method in 2002. The name ESD was not established in those days; the name cutting endoscopic mucosal resection (EMR) or EMR with hook knife was used. The other traction methods such as external grasping forceps, internal traction, double channel scope, and double scopes method are introduced in this paper. A good strategy for creating counter traction makes ESD easier.

  9. Insufficient generation of mycobactericidal mediators and inadequate level of phagosomal maturation are related with susceptibility to virulent Mycobacterium tuberculosis infection in mouse macrophages

    Directory of Open Access Journals (Sweden)

    Hyo-Ji eLee

    2016-04-01

    Full Text Available Tuberculosis is caused by Mycobacterium tuberculosis (M. tuberculosis, Mtb infection, and it remains major life-threatening infectious diseases worldwide. Although Mtb has infected one-third of the present human population, only 5-10% of immunocompetent individuals are genetically susceptible to tuberculosis. All inbred strains of mice are susceptible to tuberculosis; however, some mouse strains are much more susceptible than others. In a previous report, we showed that Th1-mediated immunity was not responsible for the differential susceptibility between mouse models. To examine whether these susceptibility differences between inbred mouse strains are due to the insufficient production of effector molecules in the early stage of innate immunity, we investigated mycobacteriostatic function of bone marrow-derived macrophages (BMDMs in resistant (BALB/c and C57BL/6 and susceptible strains (DBA/2 that were infected with virulent Mtb (H37Rv or attenuated Mtb (H37Ra. The growth rate of virulent Mtb in infected cells was significantly higher in DBA/2 BMDMs, whereas the growth of the attenuated strain was similar in the three inbred mouse BMDM strains. In addition, the death rate of Mtb-infected cells increased with the infectious dose when DBA/2 BMDMs were infected with H37Rv. The intracellular reactive oxygen species (ROS level was lower in DBA/2 BMDMs that were infected with virulent Mtb at an early post-infection time point. The expression levels of phagosomal maturation markers, including early endosomal antigen-1 (EEA1 and lysosome-associated membrane protein-1 (LAMP-1, were significantly decreased in DBA/2 BMDM that were infected with virulent Mtb, whereas IFNγ-treatment restored the phagosomal maturation activity. The nitric oxide (NO production levels were also significantly lower in DBA/2 BMDMs that were infected with virulent H37Rv at late post infection points; however, this was not observed with the attenuated H37Ra strain. Furthermore

  10. The Omega Counter, a Frequency Counter Based on the Linear Regression

    CERN Document Server

    Rubiola, E; Bourgeois, P -Y; Vernotte, F

    2015-01-01

    This article introduces the {\\Omega} counter, a frequency counter -- or a frequency-to-digital converter, in a different jargon -- based on the Linear Regression (LR) algorithm on time stamps. We discuss the noise of the electronics. We derive the statistical properties of the {\\Omega} counter on rigorous mathematical basis, including the weighted measure and the frequency response. We describe an implementation based on a SoC, under test in our laboratory, and we compare the {\\Omega} counter to the traditional {\\Pi} and {\\Lambda} counters. The LR exhibits optimum rejection of white phase noise, superior to that of the {\\Pi} and {\\Lambda} counters. White noise is the major practical problem of wideband digital electronics, both in the instrument internal circuits and in the fast processes which we may want to measure. The {\\Omega} counter finds a natural application in the measurement of the Parabolic Variance, described in the companion article arXiv:1506.00687 [physics.data-an].

  11. Instability of counter-rotating stellar disks

    Science.gov (United States)

    Hohlfeld, R. G.; Lovelace, R. V. E.

    2015-09-01

    We use an N-body simulation, constructed using GADGET-2, to investigate an accretion flow onto an astrophysical disk that is in the opposite sense to the disk's rotation. In order to separate dynamics intrinsic to the counter-rotating flow from the impact of the flow onto the disk, we consider an initial condition in which the counter-rotating flow is in an annular region immediately exterior the main portion of the astrophysical disk. Such counter-rotating flows are seen in systems such as NGC 4826 (known as the "Evil Eye Galaxy"). Interaction between the rotating and counter-rotating components is due to two-stream instability in the boundary region. A multi-armed spiral density wave is excited in the astrophysical disk and a density distribution with high azimuthal mode number is excited in the counter-rotating flow. Density fluctuations in the counter-rotating flow aggregate into larger clumps and some of the material in the counter-rotating flow is scattered to large radii. Accretion flow processes such as this are increasingly seen to be of importance in the evolution of multi-component galactic disks.

  12. 21 CFR 866.2170 - Automated colony counter.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony counter. (a) Identification. An automated colony counter is a mechanical device intended for...

  13. Taming Past LTL and Flat Counter Systems

    CERN Document Server

    Demri, Stéphane; sangnier, Arnaud

    2012-01-01

    Reachability and LTL model-checking problems for flat counter systems are known to be decidable but whereas the reachability problem can be shown in NP, the best known complexity upper bound for the latter problem is made of a tower of several exponentials. Herein, we show that the problem is only NP-complete even if LTL admits past-time operators and arithmetical constraints on counters. Actually, the NP upper bound is shown by adequately combining a new stuttering theorem for Past LTL and the property of small integer solutions for quantifier-free Presburger formulae. Other complexity results are proved, for instance for restricted classes of flat counter systems.

  14. GEIGER-MULLER TYPE COUNTER TUBE

    Science.gov (United States)

    Fowler, I.L.; Watt, L.A.K.

    1959-12-15

    A single counter tube capable of responding to a wide range of intensities is described. The counter tube comprises a tubular cathode and an anode extending centrally of the cathode. The spacing between the outer surface of the anode and the inner surface of the cathode is varied along the length of the tube to provide different counting volumes in adjacent portions of the tube. A large counting volume in one portion adjacent to a low-energy absorption window gives adequate sensitivity for measuring lowintensity radiation, while a smaller volume with close electrode spacing is provided in the counter to make possible measurement of intense garnma radiation fields.

  15. Time interleaved counter analog to digital converters

    OpenAIRE

    Danesh, Seyed Amir Ali

    2011-01-01

    The work explores extending time interleaving in A/D converters, by applying a high-level of parallelism to one of the slowest and simplest types of data-converters, the counter ADC. The motivation for the work is to realise high-performance re-configurable A/D converters for use in multi-standard and multi-PHY communication receivers with signal bandwidths in the 10s to 100s of MHz. The counter ADC requires only a comparator, a ramp signal, and a digital counter, where the ...

  16. Eupafolin inhibits PGE2 production and COX2 expression in LPS-stimulated human dermal fibroblasts by blocking JNK/AP-1 and Nox2/p47{sup phox} pathway

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Ming-Horng [Department of Pediatrics, Division of Neonatology and Pediatric Hematology/Oncology, Chang Gung Memorial Hospital, Yunlin, Taiwan (China); Lin, Zih-Chan [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Liang, Chan-Jung [Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Yen, Feng-Lin [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Institute of Biomedical Sciences, Sun Yat-Sen University, 70 Lienhai Rd., Kaohsiung, Taiwan (China); Chiang, Yao-Chang [Center for Drug Abuse and Addiction, China Medical University Hospital, Taichung, Taiwan (China); China Medical University, Taichung, Taiwan (China); Lee, Chiang-Wen, E-mail: cwlee@gw.cgust.edu.tw [Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi, Taiwan (China); Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi, Taiwan (China); Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan (China)

    2014-09-01

    Eupafolin, a major active component found in the methanol extracts of Phyla nodiflora, has been used to treat inflammation of skin. We examined its effects on cyclooxygenase-2 (COX-2) expression in LPS-treated human dermal fibroblasts. Lipopolysaccharide (LPS) significantly increased prostaglandin-E2 (PGE2) production associated with increased COX-2 expression in Hs68 cells. This effect was blocked by eupafolin, TLR-4 antibody, antioxidants (APO and NAC), as well as inhibitors, including U0126 (ERK1/2), SB202190 (p38), SP600125 (JNK1/2), and Tanshinone IIA (AP-1). In gene regulation level, qPCR and promoter assays revealed that COX-2 expression was attenuated by eupafolin. In addition, eupafolin also ameliorated LPS-induced p47 phox activation and decreased reactive oxygen species (ROS) generation and NADPH oxidase (Nox) activity. Moreover, pretreatment with eupafolin and APO led to reduced LPS-induced phosphorylation of ERK1/2, JNK, and p38. Further, eupafolin attenuated LPS-induced increase in AP-1 transcription factor binding activity as well as the increase in the phosphorylation of c-Jun and c-Fos. In vivo studies have shown that in dermal fibroblasts of LPS treated mice, eupafolin exerted anti-inflammation effects by decreasing COX-2 protein levels. Our results reveal a novel mechanism for anti-inflammatory and anti-oxidative effects of eupafolin that involved inhibition of LPS-induced ROS generation, suppression of MAPK phosphorylation, diminished DNA binding activity of AP-1 and attenuated COX-2 expression leading to reduced production of prostaglandin E2 (PGE2). Our results demonstrate that eupafolin may be used to treat inflammatory responses associated with dermatologic diseases. - Highlights: • LPS activates the Nox2/p47{sup phox}/JNK/AP-1 and induces COX2 expression in Hs68 cells. • Eupafolin inhibits LPS-induced COX-2 expression via Nox2/p47{sup phox} inhibition. • Eupafolin may be used in the treatment of skin diseases involving inflammation.

  17. Permanent traffic counters maintained by the NMDOT

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — A point dataset representing the permanent traffic counters maintained by the NMDOT. Event mapped dataset by LRS info provided by Traffic group.

  18. Development of a Mobile Ice Nucleus Counter

    Energy Technology Data Exchange (ETDEWEB)

    Kok, Gregory [Droplet Measurement Technologies, Boulder, CO (United States); Kulkarni, Gourihar [Droplet Measurement Technologies, Boulder, CO (United States)

    2014-07-10

    An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70°C, and a single stage system can operate the warm wall at -45C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

  19. Development of a Mobile Ice Nucleus Counter

    Energy Technology Data Exchange (ETDEWEB)

    Kok, Gregory; Kulkarni, Gourihar

    2014-07-10

    An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70 deg C, and a single stage system can operate the warm wall at -45 deg C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

  20. Lifetime characteristics of Gaiger-Muller counters

    Directory of Open Access Journals (Sweden)

    Kartalović Nenad M.

    2016-01-01

    Full Text Available This paper discusses the process of functional aging of Geiger-Muller counters. Two types of Geiger-Muller counter chambers were characterized in an experiment using a combined constant voltage. Chamber A had a coaxial geometry and chamber B had a plan-parallel geometry. The experimental results indicate that the aging process was faster in the case of chambers with a coaxial geometry. The results are explained based on the process of electrical discharges in gasses.

  1. Novel Designs of Quantum Reversible Counters

    Science.gov (United States)

    Qi, Xuemei; Zhu, Haihong; Chen, Fulong; Zhu, Junru; Zhang, Ziyang

    2016-11-01

    Reversible logic, as an interesting and important issue, has been widely used in designing combinational and sequential circuits for low-power and high-speed computation. Though a significant number of works have been done on reversible combinational logic, the realization of reversible sequential circuit is still at premature stage. Reversible counter is not only an important part of the sequential circuit but also an essential part of the quantum circuit system. In this paper, we designed two kinds of novel reversible counters. In order to construct counter, the innovative reversible T Flip-flop Gate (TFG), T Flip-flop block (T_FF) and JK flip-flop block (JK_FF) are proposed. Based on the above blocks and some existing reversible gates, the 4-bit binary-coded decimal (BCD) counter and controlled Up/Down synchronous counter are designed. With the help of Verilog hardware description language (Verilog HDL), these counters above have been modeled and confirmed. According to the simulation results, our circuits' logic structures are validated. Compared to the existing ones in terms of quantum cost (QC), delay (DL) and garbage outputs (GBO), it can be concluded that our designs perform better than the others. There is no doubt that they can be used as a kind of important storage components to be applied in future low-power computing systems.

  2. Human Peritoneal Mesothelial Cell Death Induced by High-Glucose Hypertonic Solution Involves Ca2+ and Na+ Ions and Oxidative Stress with the Participation of PKC/NOX2 and PI3K/Akt Pathways

    Directory of Open Access Journals (Sweden)

    Felipe Simon

    2017-06-01

    Full Text Available Chronic peritoneal dialysis (PD therapy is equally efficient as hemodialysis while providing greater patient comfort and mobility. Therefore, PD is the treatment of choice for several types of renal patients. During PD, a high-glucose hyperosmotic (HGH solution is administered into the peritoneal cavity to generate an osmotic gradient that promotes water and solutes transport from peritoneal blood to the dialysis solution. Unfortunately, PD has been associated with a loss of peritoneal viability and function through the generation of a severe inflammatory state that induces human peritoneal mesothelial cell (HPMC death. Despite this deleterious effect, the precise molecular mechanism of HPMC death as induced by HGH solutions is far from being understood. Therefore, the aim of this study was to explore the pathways involved in HGH solution-induced HPMC death. HGH-induced HPMC death included influxes of intracellular Ca2+ and Na+. Furthermore, HGH-induced HPMC death was inhibited by antioxidant and reducing agents. In line with this, HPMC death was induced solely by increased oxidative stress. In addition to this, the cPKC/NOX2 and PI3K/Akt intracellular signaling pathways also participated in HGH-induced HPMC death. The participation of PI3K/Akt intracellular is in agreement with previously shown in rat PMC apoptosis. These findings contribute toward fully elucidating the underlying molecular mechanism mediating peritoneal mesothelial cell death induced by high-glucose solutions during peritoneal dialysis.

  3. Detecting the Elusive Blazar Counter-Jets

    CERN Document Server

    Liodakis, I; Angelakis, E

    2016-01-01

    Detection of blazar pc scale counter-jets is difficult, but it can provide invaluable insight into the relativistic effects, radiative processes and the complex mechanisms of jet production, collimation and accelation in blazars. We build on recent populations models (optimized using the MOJAVE apparent velocity and redshift distributions) in order to derive the distribution of jet-to-counter-jet ratios and the flux densities of the counter-jet at different frequencies, in an effort to set minimum sensitivity limits required for existing and future telescope arrays in order to detect these elusive counter-jets. We find that: for the BL Lacs $5\\%$ of their counter-jets have a flux-density higher than 100mJy, $15\\%$ are higher than 10 mJy, and $32\\%$ have higher flux-density than 1 mJy, whereas for the FSRQs $8\\%$ have a flux-density higher than 10mJy, $17\\%$ are higher than 1 mJy, and $32\\%$ are higher than 0.1 mJy (at 15 GHz). Future telescopes like the SKA and newly operating like e-MERLIN and JVLA may detec...

  4. Neutron spectroscopy with the Spherical Proportional Counter

    CERN Document Server

    Bougamont, E; Derre, J; Galan, J; Gerbier, G; Giomataris, I; Gros, M; Katsioulas, I; Jourde, D; Magnier, P; Navick, X F; Papaevangelou, T; Savvidis, I; Tsiledakis, G

    2015-01-01

    A novel large volume spherical proportional counter, recently developed, is used for neutron measurements. Gas mixtures of $N_{2}$ with $C_{2}H_{6}$ and pure $N_{2}$ are studied for thermal and fast neutron detection, providing a new way for the neutron spectroscopy. The neutrons are detected via the ${}^{14}N(n, p)C^{14}$ and ${}^{14}N(n, \\alpha)B^{11}$ reactions. Here we provide studies of the optimum gas mixture, the gas pressure and the most appropriate high voltage supply on the sensor of the detector in order to achieve the maximum amplification and better resolution. The detector is tested for thermal and fast neutrons detection with a ${}^{252}Cf$ and a ${}^{241}Am-{}^{9}Be$ neutron source. The atmospheric neutrons are successfully measured from thermal up to several MeV, well separated from the cosmic ray background. A comparison of the spherical proportional counter with the current available neutron counters is also given.

  5. The AMS-01 Aerogel Threshold Cherenkov counter

    Energy Technology Data Exchange (ETDEWEB)

    Barancourt, D.; Barao, F.; Barbier, G.; Barreira, G.; Buenerd, M.; Castellini, G.; Choumilov, E.; Favier, J.; Fouque, N.; Gougas, A.; Hermel, V.; Kossakowski, R.; Laborie, G.; Laurenti, G.; Lee, S.-C.; Mayet, F. E-mail: frederic.mayet@isn.in2p3.fr; Meillon, B.; Oyang, Y.-T.; Plyaskin, V.; Pojidaev, V.; Rossin, C.; Santos, D.; Vezzu, F.; Vialle, J.P

    2001-06-11

    The Alpha Magnetic Spectrometer in a precursor version (AMS-01), was flown in June 1998 on a 51.6 deg. orbit and at altitudes ranging between 320 and 390 km, on board of the space shuttle Discovery (flight STS-91). AMS-01 included an Aerogel Threshold Cherenkov counter (ATC) to separate p-bar from e{sup -} and e{sup +} from p, for momenta below 3.5 GeV/c. This paper presents a description of the ATC counter and reports on its performances during the flight STS-91.

  6. The AMS-01 Aerogel Threshold Cherenkov counter

    CERN Document Server

    Barancourt, D; Barbier, G; Barreira, G; Buénerd, M; Castellini, G; Choumilov, E; Favier, Jean; Fouque, N; Gougas, Andreas; Hermel, V; Kossakowski, R; Laborie, G; Laurenti, G; Lee, S C; Mayet, F; Meillon, B; Oyang, J Y T; Plyaskin, V; Pozhidaev, V; Rossin, C; Santos, D; Vezzu, F; Vialle, J P

    2001-01-01

    The Alpha Magnetic Spectrometer in a precursor version (AMS-01), was flown in June 1998 on a 51.6 degrees orbit and at altitudes ranging between 320 and 390 km, on board of the space shuttle Discovery (flight STS-91). AMS-01 included an Aerogel Threshold Cherenkov counter (ATC) to separate antiprotons from electrons and positrons from protons, for momenta below 3.5 GeV/c. This paper presents a description of the ATC counter and reports on its performances during the flight STS-91.

  7. Analysis of counter-rotating wind turbines

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Zakkam, Vinod Arun Kumar; Sørensen, Jens Nørkær

    2007-01-01

    This paper presents a study on the performance of a wind turbine with two counter-rotating (CRWT) rotors. The characteristics of the two counter-rotating rotors are on a 3-bladed Nordtank 500 kW rotor. The analysis has been carried out by using an Actuator Line technique implemented in the Navier......-Stokes code EllipSys3D. The analysis shows that the Annual Energy Production can be increased to about 43.5 %, as compared to a wind turbine with a single rotor. In order to determine the optimal settings of the CRWT turbine, parameters such as distance between two rotors and rotational speed have been...

  8. Development of DUPIC safeguards neutron counter

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Gil; Cha, Hong Ryul; Kim, Ho Dong; Hong, Jong Sook; Kang, Hee Young

    1999-08-01

    KAERI, in cooperation with LANL, developed DSNC (DUPIC Safeguards Neutron Counter) for safeguards implementing on DUPIC process which is under development by KAERI for direct use of spent PWR fuel in CANDU reactors. DSNC is a well-type neutron coincidence counter with substantial shielding to protect system from high gamma radiation of spent fuel. General development procedures in terms of design, manufacturing, fabrication, cold and hot test, performance test for DSNC authentication by KAERI-IAEA-LANL are described in this report. It is expected that the techniques related DSNC development and associated neutron detection and evaluation method could be applied for safeguards improvement. (Author). 20 refs., 16 tabs. 98 figs.

  9. Development of DUPIC safeguards neutron counter

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Gil; Cha, Hong Ryul; Kim, Ho Dong; Hong, Jong Sook; Kang, Hee Young

    1999-08-01

    KAERI, in cooperation with LANL, developed DSNC (DUPIC Safeguards Neutron Counter) for safeguards implementing on DUPIC process which is under development by KAERI for direct use of spent PWR fuel in CANDU reactors. DSNC is a well-type neutron coincidence counter with substantial shielding to protect system from high gamma radiation of spent fuel. General development procedures in terms of design, manufacturing, fabrication, cold and hot test, performance test for DSNC authentication by KAERI-IAEA-LANL are described in this report. It is expected that the techniques related DSNC development and associated neutron detection and evaluation method could be applied for safeguards improvement. (Author). 20 refs., 16 tabs. 98 figs.

  10. Gene transfer and expression in human neutrophils. The phox homology domain of p47phox translocates to the plasma membrane but not to the membrane of mature phagosomes

    Directory of Open Access Journals (Sweden)

    Brzezinska Agnieszka A

    2006-12-01

    Full Text Available Abstract Background Neutrophils are non-dividing cells with poor survival after isolation. Consequently, exogenous gene expression in neutrophils is challenging. We report here the transfection of genes and expression of active proteins in human primary peripheral neutrophils using nucleofection. Results Exogenous gene expression in human neutrophils was achieved 2 h post-transfection. We show that neutrophils transfected by nucleofection are functional cells, able to respond to soluble and particulate stimuli. They conserved the ability to undergo physiological processes including phagocytosis. Using this technique, we were able to show that the phox homology (PX domain of p47phox localizes to the plasma membrane in human neutrophils. We also show that RhoB, but not the PX domain of p47phox, is translocated to the membrane of mature phagosomes. Conclusion We demonstrated that cDNA transfer and expression of exogenous protein in human neutrophils is compatible with cell viability and is no longer a limitation for the study of protein function in human neutrophils.

  11. Upaya Perumusan Prinsip Counter Accounting Melalui Filosofi Punk Sebagai Counter Culture

    Directory of Open Access Journals (Sweden)

    Dayno Utama

    2015-12-01

    Full Text Available The aim of this research is to demonstrate that resistance to mainstream research contained in top/elite accounting journals for sparking creativity and innovation unconsciously has utilized the philosophy of punk. The research method of this research is argumentation technique. The result of this research shows that the philosophy of punk as counter culture can be utilized for accounting research through formulation the accounting principles namely counter accounting. Creative and innovative accounting as forms of counter accounting towards mainstream accounting tradition especially in elite journals, will not pervade in a short time.

  12. COUNTER-ROTATION IN RELATIVISTIC MAGNETOHYDRODYNAMIC JETS

    Energy Technology Data Exchange (ETDEWEB)

    Cayatte, V.; Sauty, C. [Laboratoire Univers et Théories, Observatoire de Paris, UMR 8102 du CNRS, Université Paris Diderot, F-92190 Meudon (France); Vlahakis, N.; Tsinganos, K. [Department of Astrophysics, Astronomy and Mechanics, Faculty of Physics, University of Athens, 15784 Zografos, Athens (Greece); Matsakos, T. [Department of Astronomy and Astrophysics, The University of Chicago, Chicago, IL 60637 (United States); Lima, J. J. G., E-mail: veronique.cayatte@obspm.fr [Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal)

    2014-06-10

    Young stellar object observations suggest that some jets rotate in the opposite direction with respect to their disk. In a recent study, Sauty et al. showed that this does not contradict the magnetocentrifugal mechanism that is believed to launch such outflows. Motion signatures that are transverse to the jet axis, in two opposite directions, have recently been measured in M87. One possible interpretation of this motion is that of counter-rotating knots. Here, we extend our previous analytical derivation of counter-rotation to relativistic jets, demonstrating that counter-rotation can indeed take place under rather general conditions. We show that both the magnetic field and a non-negligible enthalpy are necessary at the origin of counter-rotating outflows, and that the effect is associated with a transfer of energy flux from the matter to the electromagnetic field. This can be realized in three cases: if a decreasing enthalpy causes an increase of the Poynting flux, if the flow decelerates, or if strong gradients of the magnetic field are present. An illustration of the involved mechanism is given by an example of a relativistic magnetohydrodynamic jet simulation.

  13. Can counter-stereotypes boost flexible thinking?

    NARCIS (Netherlands)

    M.A. Goclowska; R.J. Crisp; K. Labuschagne

    2012-01-01

    To reduce prejudice psychologists design interventions requiring people to think of counter-stereotypes (i.e., people who defy stereotypic expectations—a strong woman, a Black President). Grounded in the idea that stereotypes constrain the ability to think flexibly, we propose that thinking of count

  14. International perspectives on countering school segregation

    NARCIS (Netherlands)

    Bakker, J.T.A.; Denessen, E.J.P.G.; Peters, T.J.M.; Walraven, G.

    2010-01-01

    School segregation is perceived as an unyielding problem worldwide, which is manifest along both ethnic and socio-economic lines. With this edited volume we aim to share information about school segregation and policies focused on countering school segregation from an international perspective. Many

  15. Counter Trafficking System Development "Analysis Training Program"

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Dennis C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-12-01

    This document will detail the training curriculum for the Counter-Trafficking System Development (CTSD) Analysis Modules and Lesson Plans are derived from the United States Military, Department of Energy doctrine and Lawrence Livermore National Laboratory (LLNL), Global Security (GS) S Program.

  16. Can counter-stereotypes boost flexible thinking?

    NARCIS (Netherlands)

    Goclowska, M.A.; Crisp, R.J.; Labuschagne, K.

    2013-01-01

    To reduce prejudice psychologists design interventions requiring people to think of counter-stereotypes (i.e., people who defy stereotypic expectations—a strong woman, a Black President). Grounded in the idea that stereotypes constrain the ability to think flexibly, we propose that thinking of count

  17. Cerenkov counters at the Omega Facility

    CERN Multimedia

    1975-01-01

    P. Petroff on the left. Here one sees both the gas Cerenkov counters sitting in front of the magnet to select forward emitted particles. The smaller one, working at high pressure, sits nearest to the Omega magnet (see photo 7505073X), the other (see photo 7505071X) works at atmospheric pressure.

  18. One-Counter Markov Decision Processes

    NARCIS (Netherlands)

    Brazdil, T.; Brozek, V.; Etessami, K.; Kucera, A.; Wojtczak, D.K.; Charikar, M.

    2010-01-01

    We study the computational complexity of central analysis problems for One-Counter Markov Decision Processes (OC-MDPs), a class of finitely-presented, countable-state MDPs. OC-MDPs are equivalent to a controlled extension of (discrete-time) Quasi-Birth-Death processes (QBDs), a stochastic model stud

  19. Ultrafine Condensation Particle Counter Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Kuang, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-01

    The Model 3776 Ultrafine Condensation Particle Counter (UCPC; pictured in Appendix A) is designed for researchers interested in airborne particles smaller than 20 nm. With sensitivity to particles down to 2.5 nm in diameter, this UCPC is ideally suited for atmospheric and climate research, particle formation and growth studies, combustion and engine exhaust research, and nanotechnology research.

  20. Counter-Narratives and the Unrehearsed Stories Counter-Terrorists Unwittingly Produce.

    OpenAIRE

    Beatrice de Graaf

    2009-01-01

    Governments produce both deliberate and involuntary (and less conscious) narratives when countering terrorism. The thesis of this article is that such unintended messages can be much more powerful and consequential than is realized; in fact, they can completely contradict the intended official 'counter-narrative'. To substantiate this hypothesis, the author looks at the experience of the German Federal Republic in the 1970s and beyond when state and society were confronted with the Red Army F...

  1. 21 CFR 866.2180 - Manual colony counter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual colony counter. 866.2180 Section 866.2180...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter. (a) Identification. A manual colony counter is a device intended for medical purposes that...

  2. Mycobacterium tuberculosis Chaperonin 10 Is Secreted in the Macrophage Phagosome: Is Secretion Due to Dissociation and Adoption of a Partially Helical Structure at the Membrane?

    Science.gov (United States)

    Fossati, Gianluca; Izzo, Gaetano; Rizzi, Emanuele; Gancia, Emanuela; Modena, Daniela; Moras, Maria Luisa; Niccolai, Neri; Giannozzi, Elena; Spiga, Ottavia; Bono, Letizia; Marone, Piero; Leone, Eugenio; Mangili, Francesca; Harding, Stephen; Errington, Neil; Walters, Christopher; Henderson, Brian; Roberts, Michael M.; Coates, Anthony R. M.; Casetta, Bruno; Mascagni, Paolo

    2003-01-01

    To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that the mycobacterial protein accumulates both in the wall of the bacterium and in the matrix of the phagosomes in which ingested mycobacteria survive within infected macrophages. To understand the structural implications underlying this secretion, a structural study of M. tuberculosis Cpn10 was performed under conditions that are generally believed to mimic the membrane environment. It was found that in buffer-organic solvent mixtures, the mycobacterial protein forms two main species, namely, a partially helical monomer that prevails in dilute solutions at room temperature and a dimer that folds into a β-sheet-dominated structure and prevails in either concentrated protein solutions at room temperature or in dilute solutions at low temperature. A partially helical monomer was also found and was completely associated with negatively charged detergents in a micelle-bound state. Remarkably, zwitterionic lipids had no effect on the protein structure. By using N- and C-truncated forms of the protein, the C- and N-terminal sequences were identified as possessing an amphiphilic helical character and as selectively associating with acidic detergent micelles. When the study was extended to other chaperonins, it was found that human Cpn10 is also monomeric and partially helical in dilute organic solvent-buffer mixtures. In contrast, Escherichia coli Cpn10 is mostly dimeric and predominately β-sheet in both dilute and concentrated solutions. Interestingly, human Cpn10 also crosses biological membranes, whereas the E. coli homologue is strictly cytosolic. These results suggest that dissociation to partially helical monomers and interaction with acidic lipids may be two important steps in the mechanism of secretion of M. tuberculosis Cpn10 to the external environment. PMID:12837802

  3. Track reconstruction in the BESⅢ muon counter

    Institute of Scientific and Technical Information of China (English)

    LIANG Yu-Tie; LIU Kun; YOU Zheng-Yun; MAO Ya-Jun; LI Wei-Dong; BIAN Jian-Ming; CAO Guo-Fu; CAO Xue-Xiang; CHEN Shen-Jian; DENG Zi-Yan; FU Cheng-Dong; GAO Yuan-Ning; HAN Lei; HAN Shao-Qing; HE Kang-Lin; HE Miao; HU Ji-Feng; HU Xiao-Wei; HUANG Bin; HUANG Xing-Tao; JIA Lu-Kui; JI Xiao-Bin; LI Hai-Bo; LIU Bei-Jiang; LIU Chun-Xiu; LIU Huai-Min; LIU Ying; LIU Yong; LUO Tao; Lü Qi-Wen; MA Qiu-Mei; MA Xiang; MAO Ze-Pu; MO Xiao-Hu; NING Fei-Peng; PING Rong-Gang; QIU Jin-Fa; SONG Wen-Bo; SUN Sheng-Sen; SUN Xiao-Dong; SUN Yong-Zhao; TIAN Hao-Lai; WANG Ji-Ke; WANG Liang-Liang; WEN Shuo-Pin; WU Ling-Hui; WU Zhi; XIE Yu-Guang; XU Min; YAN Jie; YAN Liang; YAO Jian; YUAN Chang-Zheng; YUAN Ye; ZHANG Chang-Chun; ZHANG Jian-Yong; ZHANG Lei; ZHANG Xue-Yao; ZHANG Yao; ZHENG Yang-Heng; ZHU Yong-Sheng; ZOU Jia-Heng

    2009-01-01

    The reconstruction algorithm for BESⅢ Muon Counter, MucRecAlg, is developed with the object-oriented language C++ in BESⅢ offline software environment. MucRecAlg consists of the following functions: to find track seeds either from extrapolation of tracks in the main drift chamber or from the fired strips in muon counter, to select fired strips associated to the candidate tracks, to fit the candidate tracks with a linear or quadratic function and to calculate other parameters of the tracks for muon identification. Monte Carlo samples are generated to check the performance of the reconstruction package, such as reconstruction efficiency, muon remaining rate and pion rejection rate, etc. The preliminary results show that the pion rejection rate is around 3%-4% while the muon remaining rate is better than 90% in 0.4-1.6 GeV/c momentum region, which meets the requirement as shown in the design report.

  4. Neutron counter based on beryllium activation

    Energy Technology Data Exchange (ETDEWEB)

    Bienkowska, B.; Prokopowicz, R.; Kaczmarczyk, J.; Paducha, M. [Institute of Plasma Physics and Laser Microfusion (IPPLM), Hery 23, 01-497 Warsaw (Poland); Scholz, M.; Igielski, A. [Institute of Nuclear Physics PAS (IFJPAN), Radzikowskiego 152, 31-342 Krakow (Poland); Karpinski, L. [Faculty of Electrical Engineering, Rzeszow University of Technology, Pola 2, 35-959 Rzeszow (Poland); Pytel, K. [National Centre for Nuclear Research (NCBJ), Soltana 7, 05-400 Otwock - Swierk (Poland)

    2014-08-21

    The fusion reaction occurring in DD plasma is followed by emission of 2.45 MeV neutrons, which carry out information about fusion reaction rate and plasma parameters and properties as well. Neutron activation of beryllium has been chosen for detection of DD fusion neutrons. The cross-section for reaction {sup 9}Be(n, α){sup 6}He has a useful threshold near 1 MeV, which means that undesirable multiple-scattered neutrons do not undergo that reaction and therefore are not recorded. The product of the reaction, {sup 6}He, decays with half-life T{sub 1/2} = 0.807 s emitting β{sup −} particles which are easy to detect. Large area gas sealed proportional detector has been chosen as a counter of β–particles leaving activated beryllium plate. The plate with optimized dimensions adjoins the proportional counter entrance window. Such set-up is also equipped with appropriate electronic components and forms beryllium neutron activation counter. The neutron flux density on beryllium plate can be determined from the number of counts. The proper calibration procedure needs to be performed, therefore, to establish such relation. The measurements with the use of known β–source have been done. In order to determine the detector response function such experiment have been modeled by means of MCNP5–the Monte Carlo transport code. It allowed proper application of the results of transport calculations of β{sup −} particles emitted from radioactive {sup 6}He and reaching proportional detector active volume. In order to test the counter system and measuring procedure a number of experiments have been performed on PF devices. The experimental conditions have been simulated by means of MCNP5. The correctness of simulation outcome have been proved by measurements with known radioactive neutron source. The results of the DD fusion neutron measurements have been compared with other neutron diagnostics.

  5. Neutron counter based on beryllium activation

    Science.gov (United States)

    Bienkowska, B.; Prokopowicz, R.; Scholz, M.; Kaczmarczyk, J.; Igielski, A.; Karpinski, L.; Paducha, M.; Pytel, K.

    2014-08-01

    The fusion reaction occurring in DD plasma is followed by emission of 2.45 MeV neutrons, which carry out information about fusion reaction rate and plasma parameters and properties as well. Neutron activation of beryllium has been chosen for detection of DD fusion neutrons. The cross-section for reaction 9Be(n, α)6He has a useful threshold near 1 MeV, which means that undesirable multiple-scattered neutrons do not undergo that reaction and therefore are not recorded. The product of the reaction, 6He, decays with half-life T1/2 = 0.807 s emitting β- particles which are easy to detect. Large area gas sealed proportional detector has been chosen as a counter of β-particles leaving activated beryllium plate. The plate with optimized dimensions adjoins the proportional counter entrance window. Such set-up is also equipped with appropriate electronic components and forms beryllium neutron activation counter. The neutron flux density on beryllium plate can be determined from the number of counts. The proper calibration procedure needs to be performed, therefore, to establish such relation. The measurements with the use of known β-source have been done. In order to determine the detector response function such experiment have been modeled by means of MCNP5-the Monte Carlo transport code. It allowed proper application of the results of transport calculations of β- particles emitted from radioactive 6He and reaching proportional detector active volume. In order to test the counter system and measuring procedure a number of experiments have been performed on PF devices. The experimental conditions have been simulated by means of MCNP5. The correctness of simulation outcome have been proved by measurements with known radioactive neutron source. The results of the DD fusion neutron measurements have been compared with other neutron diagnostics.

  6. Prevent: A Fragmented Counter-Terrorism Strategy

    Science.gov (United States)

    2015-05-21

    of the Prevent strategy. The British counter-insurgency experiences in Malaysia provide an invaluable insight into the historical lessons of...cultural diversity , and language are recognized, it becomes easier to appreciate why a separation from the rest of the United Kingdom’s society is...autonomy in Malaysia reflect a similar dichotomy that the OSCT and DCLG face today. The Prevent strategy of decentralized control and emphasis on local

  7. Light Obscuration Particle Counter Fuel Contamination Limits

    Science.gov (United States)

    2015-10-08

    4) (5). The Army utilizes ASTM D4176 – Standard Test Method for Free Water and Particulate Contamination in Distillate Fuels (Visual Inspection ...where high in the 4µm (c) channel only. 78 samples where aviation fuels (JP-8 and F-24) that where high in the 6µm (c),14µm (c), and/or 30µm (c...AND USE OF LIQUID FUELS Charleston, South Carolina USA 4-8 October 2015 LIGHT OBSCURATION PARTICLE COUNTER FUEL CONTAMINATION LIMITS Joel

  8. Hardware support for software controlled fast multiplexing of performance counters

    Science.gov (United States)

    Salapura, Valentina; Wisniewski, Robert W.

    2013-01-01

    Performance counters may be operable to collect one or more counts of one or more selected activities, and registers may be operable to store a set of performance counter configurations. A state machine may be operable to automatically select a register from the registers for reconfiguring the one or more performance counters in response to receiving a first signal. The state machine may be further operable to reconfigure the one or more performance counters based on a configuration specified in the selected register. The state machine yet further may be operable to copy data in selected one or more of the performance counters to a memory location, or to copy data from the memory location to the counters, in response to receiving a second signal. The state machine may be operable to store or restore the counter values and state machine configuration in response to a context switch event.

  9. 疏风通络方对哮喘大鼠嗜酸细胞跨膜迁移相关因子VCAM-1/PI3K/Rac-1/NOX2/NOX4/SHP-2表达影响的研究%Influence of Shufeng Tongluo prescription on expression of VCAM-1/PI3K/Rac-1/NOX2/NOX4/SHP-2 related factors in eosinophils transendothelia migration in lung of rats with asthma

    Institute of Scientific and Technical Information of China (English)

    刘贵颖; 张慧琪; 尹新中; 朱振刚; 刘旻; 乔亚珍; 窦迎婷; 刘文彬; 刘超武

    2013-01-01

    [目的]探讨疏风通络方对哮喘大鼠嗜酸细胞跨膜迁移的影响.[方法]选择SPF级雄性Wistar大鼠70只为研究对象,随机分为正常组、模型组、地塞米松组、DPI组、中药低、中、高剂量组,共7组,每组大鼠10只.第1天致敏:正常组给予生理盐水1 mL腹腔注射致敏,而其他6组给予1 mL造模液(含Ⅴ级卵清蛋白100 mg,氢氧化铝100 mg和灭活百日咳杆菌6×109个)腹腔注射致敏;第15天开始激发:将各组大鼠分别置于相同大小的雾化箱内,正常组给予生理盐水6 mL雾化激发,其他6组给予5%的Ⅴ级卵清蛋白溶液6 mL雾化激发,每次激发前2h正常组给予生理盐水1 mL灌胃,而其他6组给予相应的药物灌胃.各组每天激发1次,每次激发30 min,连续激发10d后处死大鼠,并采集相应标本,并进一步检测影响嗜酸细胞跨膜迁移的相关指标.[结果]模型组肺组织嗜酸细胞跨膜迁移相关调节因子血管内皮黏附分子-Ⅰ(VCAM-1)、磷脂酰肌醇3激酶(PI3K)、Rac-1、NADPH氧化酶2(NOX2)、NADPH氧化酶4(NOX4)、酪氨酸磷酸酶(SHP-2)出现高表达,高于正常组(P<0.001);各治疗组与模型组相比,地塞米松组抑制上述因子表达的效果最好(P<0.001),中药高剂量组的抑制效果略差于地塞米松组,但两者差异无统计学意义(P>0.05),氯化二联苯碘(DPI)组、中药低、中剂量组抑制效果一般.[结论]疏风通络方对哮喘大鼠嗜酸细胞跨膜迁移有一定的阻抑作用,这可能是其平喘作用机制之一.%[Objective] To explore the effect of Shufeng Tongluo decoction on eosinophils transendothelia migration in lung of rats with asthma. [Methods] Seventy Wistar rats (SPF) were randomly divided into seven groups: normal group, model group, dexamethasone group, DPI group, low-dose group of Chinese medicine, medium-dose group of Chinese medicine, and high-dose group of Chinese medicine with 10 rats in each group. The rats in normal group were

  10. Consumer Preferences for High Welfare Meat in Germany: Self-service Counter or Service Counter?

    Directory of Open Access Journals (Sweden)

    Ramona Weinrich

    2015-01-01

    Full Text Available Many people view animal welfare standards in the agricultural industry as critical and some consumers would prefer to buy high welfare meat. In order to successfully introduce high welfare meat products onto the market, some important marketing decisions must be made. Due to limited shelf space in retail outlets, niche products like high welfare meat cannot be placed both at the self-service counter and at the service counter. In order to analyze where to place it best an online survey of 642 German consumers was conducted. By means of factor and cluster analyses, consumers’ animal welfare attitudes and their preference for a point of purchase were combined. The different target groups were joint using cross tabulation analysis. The results reveal that consumers in the target group show a more positive attitude to the service counter.

  11. Counter-Narratives and the Unrehearsed Stories Counter-Terrorists Unwittingly Produce

    Directory of Open Access Journals (Sweden)

    Beatrice de Graaf

    2010-11-01

    Full Text Available Governments produce both deliberate and involuntary (and less conscious narratives when countering terrorism. The thesis of this article is that such unintended messages can be much more powerful and consequential than is realized; in fact, they can completely contradict the intended official 'counter-narrative'. To substantiate this hypothesis, the author looks at the experience of the German Federal Republic in the 1970s and beyond when state and society were confronted with the Red Army Faction (RAF and similar left-wing "revolutionaries" like those of the 2nd of June Movement or the Red Zora.

  12. Structure of the Legionella Virulence Factor, SidC Reveals a Unique PI(4P-Specific Binding Domain Essential for Its Targeting to the Bacterial Phagosome.

    Directory of Open Access Journals (Sweden)

    Xi Luo

    2015-06-01

    Full Text Available The opportunistic intracellular pathogen Legionella pneumophila is the causative agent of Legionnaires' disease. L. pneumophila delivers nearly 300 effector proteins into host cells for the establishment of a replication-permissive compartment known as the Legionella-containing vacuole (LCV. SidC and its paralog SdcA are two effectors that have been shown to anchor on the LCV via binding to phosphatidylinositol-4-phosphate [PI(4P] to facilitate the recruitment of ER proteins to the LCV. We recently reported that the N-terminal SNL (SidC N-terminal E3 Ligase domain of SidC is a ubiquitin E3 ligase, and its activity is required for the recruitment of ER proteins to the LCV. Here we report the crystal structure of SidC (1-871. The structure reveals that SidC contains four domains that are packed into an arch-like shape. The P4C domain (PI(4P binding of SidC comprises a four α-helix bundle and covers the ubiquitin ligase catalytic site of the SNL domain. Strikingly, a pocket with characteristic positive electrostatic potentials is formed at one end of this bundle. Liposome binding assays of the P4C domain further identified the determinants of phosphoinositide recognition and membrane interaction. Interestingly, we also found that binding with PI(4P stimulates the E3 ligase activity, presumably due to a conformational switch induced by PI(4P from a closed form to an open active form. Mutations of key residues involved in PI(4P binding significantly reduced the association of SidC with the LCV and abolished its activity in the recruitment of ER proteins and ubiquitin signals, highlighting that PI(4P-mediated targeting of SidC is critical to its function in the remodeling of the bacterial phagosome membrane. Finally, a GFP-fusion with the P4C domain was demonstrated to be specifically localized to PI(4P-enriched compartments in mammalian cells. This domain shows the potential to be developed into a sensitive and accurate PI(4P probe in living cells.

  13. PRELIMINARY PROGRAMMED WHOLE—BODY COUNTER

    Institute of Scientific and Technical Information of China (English)

    张少东; 郑文忠; 等

    1995-01-01

    It is capable of giving the initial intakes of radionuclides and the assessment quantitites used in radiation protection according to its measured results of radionuclides in vivo.It is accomplished by providing the software of controlling,interface and internal dose estimation programs to the original iron cabin shielding whole-body counter.The preliminary application shows that its data processing is rapid and correct,and can meet the requirement of rapid internal radioactive contamination monitoring and diagnosing in case of lots of internal contamination subjects happened in nuclear accident.

  14. Taxing junk food to counter obesity.

    Science.gov (United States)

    Franck, Caroline; Grandi, Sonia M; Eisenberg, Mark J

    2013-11-01

    We examined the advantages and disadvantages of implementing a junk food tax as an intervention to counter increasing obesity in North America. Small excise taxes are likely to yield substantial revenue but are unlikely to affect obesity rates. High excise taxes are likely to have a direct impact on weight in at-risk populations but are less likely to be politically palatable or sustainable. Ultimately, the effectiveness of earmarked health programs and subsidies is likely to be a key determinant of tax success in the fight against obesity.

  15. Shared address collectives using counter mechanisms

    Science.gov (United States)

    Blocksome, Michael; Dozsa, Gabor; Gooding, Thomas M; Heidelberger, Philip; Kumar, Sameer; Mamidala, Amith R; Miller, Douglas

    2014-02-18

    A shared address space on a compute node stores data received from a network and data to transmit to the network. The shared address space includes an application buffer that can be directly operated upon by a plurality of processes, for instance, running on different cores on the compute node. A shared counter is used for one or more of signaling arrival of the data across the plurality of processes running on the compute node, signaling completion of an operation performed by one or more of the plurality of processes, obtaining reservation slots by one or more of the plurality of processes, or combinations thereof.

  16. Cerenkov counter for the experiment NA3

    CERN Multimedia

    1978-01-01

    The program of the NA3 experiment included the study of hadronic interactions with a large transverse momentum pT, thus the inclusion in the set-up of three gas threshold Cerenkov counters of large acceptance. The photo shows the downstream part of the second Cerenkov (located at the output of the magnet). The yellow membrane is a temporary protection for the optics (shown in photo 7810540X) to be taken away when fixing this part to the gas tank (entering the magnet and not shown). The photomultipliers all around are heavily shielded.

  17. The multimodal argumentation of persuasive counter discourses

    DEFF Research Database (Denmark)

    Maier, Carmen Daniela

    are given prominence in the argumentation by examining their complex interplay and functional differentiation. The ways in which speech, writing and images articulate the counter discourse occupy a central position in the analysis. A special focus is put on the multimodal configuration of specific...... and new multimodal ways of discussing them. References Kress, G. 2010. Multimodality. A Social Semiotic Approach to Contemporary Communication. London: Routledge. Van Leeuwen, Theo. 2008. Discourse and Practice. New Tools for Critical Discourse Analysis. Oxford: Oxford University Press. Chouliaraki, L...

  18. Industrial espionage and technical surveillance counter measurers

    CERN Document Server

    Androulidakis, Iosif

    2016-01-01

    This book examines technical aspects of industrial espionage and its impact in modern companies, organizations, and individuals while emphasizing the importance of intellectual property in the information era. The authors discuss the problem itself and then provide statistics and real world cases. The main contribution provides a detailed discussion of the actual equipment, tools and techniques concerning technical surveillance in the framework of espionage. Moreover, they present the best practices and methods of detection (technical surveillance counter measures) as well as means of intellectual property protection.

  19. A new TDCR-LS counter using Channel photomultiplier tubes.

    Science.gov (United States)

    Ivan, C; Cassette, P; Sahagia, Maria

    2008-01-01

    A new Triple to Double Coincidence Ratio (TDCR) liquid scintillation (LS) counter using recently available photodetectors, the Channel photomultiplier (CPM) tubes, was constructed and tested in the framework of a scientific cooperation between IFIN-HH and LNHB. The prototype LS counter uses 3CPM tubes arranged symmetrically in an optical chamber around a standard LS vial. The behavior of the prototype was first evaluated with a light emitting diode (LED) light pulser. The counter was then compared against a TDCR counter using conventional photomultiplier tubes, by measuring (55)Fe, (3)H, (63)Ni and (90)Sr/(90)Y LS sources prepared in commercial liquid scintillation cocktails. Although the observed detection efficiency was significantly lower than the one achieved with the traditional counter, we found a remarkable agreement on the activity determination using the two counters. Details on the prototype and the measurement results obtained are discussed in this paper.

  20. Neutron pileup algorithms for multiplicity counters

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Sean M.; Stave, Sean; Lintereur, Azaree; Siciliano, Edward; Kouzes, Richard; Bliss, Mary

    2015-06-01

    Abstract The shortage of helium-3 (3He) has created a need to identify alternative neutron detection options for a variety of nuclear nonproliferation applications. One application that may be affected by 3He replacement technology is that of mass accountancy for safeguards, which utilizes coincidence and multiplicity counters to verify special nuclear material declarations. The use of neutron scintillation materials, such as LiF-ZnS sheets, as an alternative to 3He proportional tubes in multiplicity counters requires novel techniques for Pulse Shape Discrimination to distinguish between neutrons and gamma rays. These techniques must work under high count rates, as the maximum momentary rate for incoming neutrons from multiplicity events can be quite large. We have created a fast and accurate neutron discrimination algorithm based on time window filtering and signature comparison that can operate quickly on data with high degrees of gamma ray and neutron pileup. This algorithm is evaluated for its capability to separate signals as the pileup rate increases, and the possibility for implementation on fast hardware (e.g., FPGA hardware) for real-time operation is explored.

  1. Instability patterns between counter-rotating disks

    Directory of Open Access Journals (Sweden)

    F. Moisy

    2003-01-01

    Full Text Available The instability patterns in the flow between counter-rotating disks (radius to height ratio R/h from 3.8 to 20.9 are investigated experimentally by means of visualization and Particle Image Velocimetry. We restrict ourselves to the situation where the boundary layers remain stable, focusing on the shear layer instability that occurs only in the counter-rotating regime. The associated pattern is a combination of a circular chain of vortices, as observed by Lopez et al. (2002 at low aspect ratio, surrounded by a set of spiral arms, first described by Gauthier et al. (2002 in the case of high aspect ratio. Stability curve and critical modes are measured for the whole range of aspect ratios. From the measurement of a local Reynolds number based on the shear layer thickness, evidence is given that a free shear layer instability, with only weak curvature effect, is responsible for the observed patterns. Accordingly, the number of vortices is shown to scale as the shear layer radius, which results from the competition between the centrifugal effects of each disk.

  2. Neutron pileup algorithms for multiplicity counters

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Sean M., E-mail: sean.robinson@pnnl.gov [Pacific Northwest National Laboratory, Seattle, WA 98109 (United States); Stave, Sean; Lintereur, Azaree; Siciliano, Edward; Kouzes, Richard; Bliss, Mary [Pacific Northwest National Laboratory, Richland, WA 99352 (United States)

    2015-06-01

    The shortage of helium-3 ({sup 3}He) has created a need to identify alternative neutron detection options for a variety of nuclear nonproliferation applications. One application that may be affected by {sup 3}He replacement technology is that of mass accountancy for safeguards, which utilizes coincidence and multiplicity counters to verify special nuclear material declarations. The use of neutron scintillation materials, such as LiF–ZnS sheets, as an alternative to {sup 3}He proportional tubes in multiplicity counters requires novel techniques for Pulse Shape Discrimination to distinguish between neutrons and gamma rays. These techniques must work under high count rates, as the maximum momentary rate for incoming neutrons from multiplicity events can be quite large. We have created a fast and accurate neutron discrimination algorithm based on time window filtering and signature comparison that can operate quickly on data with high degrees of gamma ray and neutron pileup. This algorithm is evaluated for its capability to separate signals as the pileup rate increases, and the possibility for implementation on fast hardware (e.g., FPGA hardware) for real-time operation is explored.

  3. Silicon photomultipliers in AMIGA muon counters

    Energy Technology Data Exchange (ETDEWEB)

    Botti, Ana Martina [Institut fuer Kernphysik, Karlsruher Institut fuer Technologie (Germany); Instituto de Tecnologias en Deteccion y Astroparticulas (ITeDA) (Argentina); Collaboration: Pierre-Auger-Collaboration

    2016-07-01

    The project AMIGA (Auger Muons and Infill for the Ground Array) aims to extend the energy range at the Pierre Auger Observatory to observe cosmic rays of lower energies (down to ∝10{sup 17} eV) and to study the transition from extragalactic to galactic cosmic rays. AMIGA is compounded by an infill of surface detectors (employing Cherenkov radiation detection in water) and muon counters. The AMIGA muon counters consist of an array of buried modules composed of 64 scintillator bars, a multi-pixel Photo Multiplier Tube (PMT) and the corresponding electronic of acquisition which works along with the surface detector. Currently, ITeDA is evaluating the feasibility of replacing PMTs with silicon photomultipliers (SiPM) without performing any substantial modification in the digital readout nor in the mechanical design. I present calibration results of a prototype module associated to the surface detector Toune of the Pierre Auger Observatory using a SiPM Hamamatsu S1257-100C plugged to the standard AMIGA front-end electronics. In addition, a study concerning gain stability and temperature variation has also been performed and is reported. I finally discuss a comparison between traces measured by both photodetectors (PMT and SiPM) for modules associated to the surface detector Toune.

  4. The Brazilian military: its role in counter-drug activities.

    OpenAIRE

    Kitchener, Roy I.

    1992-01-01

    Approved for public release; distribution is unlimited This thesis examines the role of Brazil's military in counter-drug operations. Drug trafficking in Brazil poses a growing threat to the country's national security, but Brazil's physical size and limited resources have hindered the government's counter-drug efforts. The Brazilian military has been reluctant to assume a more significant role in counter-drug operations. The thesis argues that external, internal, and ...

  5. Hardware support for software controlled fast reconfiguration of performance counters

    Science.gov (United States)

    Salapura, Valentina; Wisniewski, Robert W.

    2013-06-18

    Hardware support for software controlled reconfiguration of performance counters may include a plurality of performance counters collecting one or more counts of one or more selected activities. A storage element stores data value representing a time interval, and a timer element reads the data value and detects expiration of the time interval based on the data value and generates a signal. A plurality of configuration registers stores a set of performance counter configurations. A state machine receives the signal and selects a configuration register from the plurality of configuration registers for reconfiguring the one or more performance counters.

  6. Hardware support for software controlled fast reconfiguration of performance counters

    Science.gov (United States)

    Salapura, Valentina; Wisniewski, Robert W

    2013-09-24

    Hardware support for software controlled reconfiguration of performance counters may include a plurality of performance counters collecting one or more counts of one or more selected activities. A storage element stores data value representing a time interval, and a timer element reads the data value and detects expiration of the time interval based on the data value and generates a signal. A plurality of configuration registers stores a set of performance counter configurations. A state machine receives the signal and selects a configuration register from the plurality of configuration registers for reconfiguring the one or more performance counters.

  7. A new highly segmented start counter for the CLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Sharabian, Y.G. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Battaglieri, M. [INFN Sezione di Genova, 16146 Genova (Italy); Burkert, V.D. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); DeVita, R. [INFN Sezione di Genova, 16146 Genova (Italy); Elouadrhiri, L. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Guo, L. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Kashy, D. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Kubarovsky, V. [Rensselaer Polytechnic Institute, Troy, NY 12180 and Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Mutchler, G.S. [T.W. Bonner Nuclear Laboratory, Rice University, Houton, TX 77251-1892 (United States)]. E-mail: mutchler@rice.edu; Ostrick, M. [Physikalisches Institut, Universitaet Bonn, Bonn (Germany); Ripani, M. [INFN Sezione di Genova, 16146 Genova (Italy); Rossi, P. [INFN Laboratori Nazionali di Frascati, 00044 Frascati (Italy); Rottura, A. [INFN Sezione di Genova, 16146 Genova (Italy); Pasyuk, E. [Arizona State University, Tempe, AZ, 85287-1504 (United States); Weygand, D. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States)

    2006-01-01

    The design, construction and performance of a highly segmented Start Counter are described. The Start Counter is an integral part of the trigger used in photon beam running with CLAS in Hall B at the Thomas Jefferson National Accelerator Facility (TJNAF). The Start Counter is constructed of 24 2.2-mm-thick single-ended scintillation paddles, forming a hermetic hexagon around the target region. This device measures the interaction time of the incoming photon in the target by detecting the outgoing particles. The counter provides complex trigger topologies, shows good efficiency and achieved a time resolution of 350 ps.

  8. A critique to the significance of Gettier counter-examples

    Institute of Scientific and Technical Information of China (English)

    Cao Jianbo

    2006-01-01

    Usually,people think that Gettier counter-examples challenged the traditional tripartite definition of knowledge and fundamentally changed the characteristic of the contemporary epistemology.This paper argues that regard for Gettier counter-examples is exaggerated,because(i)the JTB definition is neither an important nor a comprehensive one that covers all knowledge.Moreover,the significance of Gettier counter-examples is limited.(ii)The source of Gettier counter-examples lies in one arbitrary judgment,two mix-ups,three false assumptions,and a misunderstanding about the JTB definition.

  9. Fiber-Optic Monitoring System of Particle Counters

    Directory of Open Access Journals (Sweden)

    A. A. Titov

    2016-01-01

    Full Text Available The article considers development of a fiber-optic system to monitor the counters of particles. Presently, optical counters of particles, which are often arranged at considerable distance from each other, are used to study the saltation phenomenon. For monitoring the counters, can be used electric communication lines.However, it complicates and raises the price of system Therefore, we offered a fiber-optic system and the counter of particles, free from these shortcomings. The difference between the offered counter of particles and the known one is that the input of radiation to the counter and the output of radiation scattering on particles are made by the optical fibers, and direct radiation is entered the optical fiber rather than is delayed by a light trap and can be used for lighting the other counters thereby allowing to use their connection in series.The work involved a choice of the quartz multimode optical fiber for communication, defining the optical fiber and lenses parameters of the counter of particles, and a selection of the radiation source and the photo-detector.Using the theory of light diffraction on a particle, a measuring range of the particle sizes has been determined. The system speed has been estimated, and it has been shown that a range of communication can reach 200km.It should be noted that modulation noise of counters of particles connected in series have the impact on the useful signal. To assess the extent of this influence we have developed a calculation procedure to illustrate that with ten counters connected in series this influence on the signal-to-noise ratio will be insignificant.Thus, it has been shown that the offered fiber-optic system can be used for monitoring the counters of particles across the desertified territories. 

  10. Modelling of an IR scintillation counter

    CERN Document Server

    Fraga, M M F; Policarpo, Armando

    2000-01-01

    A systematic study of the excitation and de-excitation mechanisms in ternary gas mixtures Ar+CO sub 2 +N sub 2 is presented regarding the possibility of developing a proportional scintillation counter based on the detection of the infrared molecular emissions associated with the lowest vibrational states of molecules. The use of visible or near-infrared photons (lambda<1 mu m) for applications like imaging and quality control of microstructure detectors has been reported. In view of these applications we analyse the processes leading to near-infrared emissions in pure argon and give an estimation of the number of photons emitted per electron, at several pressures, as a function of the charge gain.

  11. Absolute calibration of TFTR helium proportional counters

    Energy Technology Data Exchange (ETDEWEB)

    Strachan, J.D.; Diesso, M.; Jassby, D.; Johnson, L.; McCauley, S.; Munsat, T.; Roquemore, A.L. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Barnes, C.W. [Princeton Univ., NJ (United States). Plasma Physics Lab.]|[Los Alamos National Lab., NM (United States); Loughlin, M. [Princeton Univ., NJ (United States). Plasma Physics Lab.]|[JET Joint Undertaking, Abingdon (United Kingdom)

    1995-06-01

    The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 msec and 50 msec depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

  12. EFFECT OF COUNTERS IN PERFORMANCE OF HADOOP

    Directory of Open Access Journals (Sweden)

    Preeti Jain

    2015-10-01

    Full Text Available Recent technological advancements have led to an overflow of data from distinctive domains (e.g., health care and scientific sensors, user-generated data, Internet and financial companies, and supply chain systems over the past two decades [1]. Big data is commonly unstructured, huge in volume and require more real-time analysis. This paper discusses a Big Data problem from NCDC for huge volume of weather data collected from various parts of world. We had generated map ( and reduce ( function for solving this problem and experimental results of these applications on a Hadoop cluster are being discussed. In this paper, performance of above application has been shown with respect to some counters available.

  13. Microstrip proportional counter development at MSFC

    Science.gov (United States)

    Fulton, M. A.; Kolodziejczak, J. J.; Ramsey, B. D.

    1992-01-01

    Microstrip detectors are an exciting new development in proportional counter design fabricated using integrated circuit-type photolithography techniques; they therefore offer very high spatial accuracy and uniformity. A development program is underway at NASA-Marshall to produce large-area microstrips for use in an X-ray detector balloon flight program and to investigate the general performance limits of these new devices. Microstrips tested so far have been fabricated both in-house using standard photolithographic techniques and by an outside contractor using electron beam technology. Various substrate materials have been tested along with different electrode configurations. The distributions of pickup on subdivided cathodes on both top and bottom surfaces of the microstrips are also being investigated for use as two-dimensional imaging detectors. Data from these tests in the development of a large-area device will be presented.

  14. Actively suspended counter-rotating machine

    Science.gov (United States)

    Studer, Philip A. (Inventor)

    1983-01-01

    A counter-rotating machine, such as a positive displacement pump having a pair of meshed, non-contacting helical screws (10,12), subjects its rotating members to axial and radial thrust forces when used for such purposes as compression of liquid or gaseous phase fluids while transporting them through a pump cavity (11,13). Each helical screw (10,12) has a shaft (17,17') which is actively suspended at opposite ends (11a,11b) of the pump cavity by a servo-controlled magnetic bearing assembly (19) and a servo-controlled rotary drive motor (20). Both bearing assemblies and drive motors are mounted on the outside of the pump cavity (11,13). Opto-electric angular position sensors (250) provide synchronization between radial orientation of the drive motors. The bearing assemblies and drive motors conjugately provide axial stabilization and radial centering of the helical screws during volumetric compression of aspirated liquid or gaseous phase fluids.

  15. Over-the-counter analgesic use.

    Science.gov (United States)

    De Broe, Marc E; Elseviers, Monique M

    2009-10-01

    Chronic analgesic nephropathy, particularly chronic interstitial nephritis and renal papillary necrosis, results from daily use for many years of mixtures containing at least two analgesics and caffeine or dependence-inducing drugs. Computed tomography scan can accurately diagnose this disease even in the absence of reliable information on previous analgesic use. The occasion to moderate regular use of aspirin and nonsteroidal anti-inflammatory drugs is without renal risk when renal function is normal. Paracetamol use is less clear although the risk is not great. The continued use of non-phenacetin-combined analgesics with or without nonsteroidal anti-inflammatory drugs is associated with faster progression toward renal impairment. As long as high-risk analgesic mixtures are available over the counter, analgesic nephropathy will continue to be a problem.

  16. The multimodal argumentation of persuasive counter discourses

    DEFF Research Database (Denmark)

    Maier, Carmen Daniela

    with the characteristics and potential fallacies of the advertising discourse of commercials. The original advertising discourse is deconstructed and reconstructed with additional visual material in front of the viewers’ eyes who are instructed by a voiceover narrator what to look at and how to identify and decode...... and critical participants in the process of message understanding. In this paper, I explore the Media Bites videos that identify and discuss problematic gender issues in commercials advertising various products. I adopt a multimodal approach in my discourse analysis and I establish which semiotic modes...... are given prominence in the argumentation by examining their complex interplay and functional differentiation. The ways in which speech, writing and images articulate the counter discourse occupy a central position in the analysis. A special focus is put on the multimodal configuration of specific...

  17. The Counter Terrorist Classroom: Religion, Education, and Security

    Science.gov (United States)

    Gearon, Liam

    2013-01-01

    The article identifies international cases--from the United States, Europe, and the United Nations--of an emergent interface of religion, education, and security. This is manifest in the uses of religion in education to counter religious extremism, the notional "counter terrorist classroom." To avoid an over-association of extremism with religion,…

  18. Majorizational Choosing of SeveralDifferent Fuzzy Counter Operator

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Different fuzzy reasoning methods were made by choosing different fuzzy operater. This article generally introduced the basic structure of fuzzy controller ,and gave several different fuzzy controllers ,and compared and analyzed different fuzzy counters in theory and computer simulating control and realized majorizational choosing of several fuzzy counters.

  19. Counter-terrorism strategies in Indonesia, Algeria and Saudi Arabia

    NARCIS (Netherlands)

    Meijer, R.; Hasan, Noorhaidi; Hendriks, B.; Janssen, F.

    2012-01-01

    This report is the result of a year-long study, conducted from March 2010 to March 2011, of the counter-terrorist strategies of three countries: Indonesia, Algeria and Saudi Arabia. The aim of this study was to acquire insight into the counter-terrorist strategies of these countries, to analyse them

  20. VLSI Architecture Of A Binary Up/Down Counter

    Science.gov (United States)

    Hsu, In-Shek; Truong, Trieu-Kie; Reed, I. S.

    1988-01-01

    Identical stages contain relatively-few logic gates. New algorithm simplifies design of binary up/down counter. Design suitable for very-large-scale integrated circuits. Contains simple "pipeline" array of identical cells. Programmable logic unit converts increment and decrement input signals to "U" and "D" signals required by algorithm of counter.

  1. The Counter Terrorist Classroom: Religion, Education, and Security

    Science.gov (United States)

    Gearon, Liam

    2013-01-01

    The article identifies international cases--from the United States, Europe, and the United Nations--of an emergent interface of religion, education, and security. This is manifest in the uses of religion in education to counter religious extremism, the notional "counter terrorist classroom." To avoid an over-association of extremism with…

  2. Dirty Fighting: How to Counter Total Warfare Mentality

    Science.gov (United States)

    2015-06-12

    DIRTY FIGHTING: HOW TO COUNTER TOTAL WARFARE MENTALITY A thesis presented to the Faculty of the U.S. Army Command and...to Counter Total Warfare Mentality Approved by: , Thesis Committee Chair LTC Sandra J. Sanchez, MBA , Member Marlyn R. Pierce...

  3. Lessons from History for Counter- Terrorism Strategic Communications

    NARCIS (Netherlands)

    Ingram, H.J.; Reed, A.G.

    2016-01-01

    Drawing on the Counter-terrorism Strategic Communication (CTSC) Project’s research paper “A Brief History of Propaganda during Conflict“, this Policy Brief lays out the key policy-relevant lessons for developing effective counter-terrorism strategic communications. It presents a framework of

  4. The Counter Terrorist Classroom: Religion, Education, and Security

    Science.gov (United States)

    Gearon, Liam

    2013-01-01

    The article identifies international cases--from the United States, Europe, and the United Nations--of an emergent interface of religion, education, and security. This is manifest in the uses of religion in education to counter religious extremism, the notional "counter terrorist classroom." To avoid an over-association of extremism with…

  5. Recent results on aerogel development for use in Cherenkov counters

    Energy Technology Data Exchange (ETDEWEB)

    Danilyuk, A.F. E-mail: danilyuk@catalysis.nsk.su; Kirillov, V.L.; Savelieva, M.D.; Bobrovnikov, V.S.; Buzykaev, A.R.; Kravchenko, E.A.; Lavrov, A.V.; Onuchin, A.P

    2002-11-21

    Synthesis of silica aerogel for Cherenkov counters is being studied for more than 10 years at the Boreskov Institute of Catalysis in collaboration with the Budker Institute of Nuclear Physics. Index of refraction, light scattering length and light absorption length are optical characteristics which determine the quality of aerogel Cherenkov counter. These parameters were measured for the aerogel produced. The results are presented.

  6. Recent results on aerogel development for use in Cherenkov counters

    CERN Document Server

    Danilyuk, A F; Savelieva, M D; Bobrovnikov, V S; Buzykaev, A R; Kravchenko, E A; Lavrov, A V; Onuchin, A P

    2002-01-01

    Synthesis of silica aerogel for Cherenkov counters is being studied for more than 10 years at the Boreskov Institute of Catalysis in collaboration with the Budker Institute of Nuclear Physics. Index of refraction, light scattering length and light absorption length are optical characteristics which determine the quality of aerogel Cherenkov counter. These parameters were measured for the aerogel produced. The results are presented.

  7. Counter-Buffing: A Visual Criticism of Guerrilla Advertising

    Science.gov (United States)

    Lauzon, Robb Conrad; Cooke, Laquana

    2017-01-01

    This article addresses and explores hip-hop's reclamation of space using transit as a public bulletin. It is situated within counter-publics discourse and couched in the theoretical frameworks offered by visual rhetorical theory. This article also discusses hip-hop counter-publics through guerrilla advertising by former graffiti artists, SKI and…

  8. Counter-terrorism strategies in Indonesia, Algeria and Saudi Arabia

    NARCIS (Netherlands)

    Meijer, R.; Hasan, Noorhaidi; Hendriks, B.; Janssen, F.

    2012-01-01

    This report is the result of a year-long study, conducted from March 2010 to March 2011, of the counter-terrorist strategies of three countries: Indonesia, Algeria and Saudi Arabia. The aim of this study was to acquire insight into the counter-terrorist strategies of these countries, to analyse

  9. Counter design influences the privacy of patients in health care

    NARCIS (Netherlands)

    Mobach, Mark P.

    2009-01-01

    A re-furnishing of counter areas in primary health care was used to assess patient privacy and its influences on the nature of conversations in a controlled experiment. Patients in two community-based pharmacies in the Netherlands were assigned to enclosed counters and a queue at distance, or to cou

  10. The IFIN-HH triple coincidence liquid scintillation counter

    CSIR Research Space (South Africa)

    Razdolescu, AC

    2006-10-01

    Full Text Available at IFIN-HH using a 3 H standard. The performances of the IFIN-HH TDCR counter was checked against the measurement results of the TDCR counters of CSIR NML (South Africa), RC (Poland) and LNHB (France). A set of ready-to-measure Ni-63 sources in liquid...

  11. Design of a novel quantum reversible ternary up-counter

    Science.gov (United States)

    Houshmand, Pouran; Haghparast, Majid

    2015-08-01

    Reversible logic has been recently considered as an interesting and important issue in designing combinational and sequential circuits. The combination of reversible logic and multi-valued logic can improve power dissipation, time and space utilization rate of designed circuits. Only few works have been reported about sequential reversible circuits and almost there are no paper exhibited about quantum ternary reversible counter. In this paper, first we designed 2-qutrit and 3-qutrit quantum reversible ternary up-counters using quantum ternary reversible T-flip-flop and quantum reversible ternary gates. Then we proposed generalized quantum reversible ternary n-qutrit up-counter. We also introduced a new approach for designing any type of n-qutrit ternary and reversible counter. According to the results, we can conclude that applying second approach quantum reversible ternary up-counter is better than the others.

  12. Electrovacuum Static Counter-Rotating Relativistic Dust Disks

    CERN Document Server

    González, G A

    2002-01-01

    A detailed study of the Counter-Rotating Model (CRM) for generic electrostatic (magnetostatic) axially symmetric thin disks without radial pressure is presented. We find a general constraint over the counter-rotating tangential velocities needed to cast the surface energy-momentum tensor of the disk as the superposition of two counter-rotating charged dust fluids. We then show that this constraint is satisfied if we take the two counter-rotating streams as circulating along electrogeodesics with equal and opposite tangential velocities. We also find explicit expressions for the energy densities, electrostatic (magnetostatic) charge densities and velocities of the counter-rotating fluids. Three specific examples are considered where we obtain some CRM well behaved based in simple solutions to the Einstein-Maxwell equations. The considered solutions are Reissner-Nordstrom in the electrostatic case, its magnetostatic counterpart and two solutions obtained from Taub-NUT and Kerr solutions.

  13. DESIGN OF TERNARY COUNTER BASED ON ADIABATIC DOMINO CIRCUIT

    Institute of Scientific and Technical Information of China (English)

    Yang Qiankun; Wang Pengjun; Zheng Xuesong

    2013-01-01

    By researching the ternary counter and low power circuit design method,a novel design of low power ternary Domino counter on switch-level is proposed.Firstly,the switch-level structure expression of ternary loop operation circuit with enable pin is derived according to the switch-signal theory,and the one bit ternary counter is obtained combining the ternary adiabatic Domino literal operation circuit and buffer.Then the switch-level structure expression of enable signal circuit is derived,and the four bits ternary counter is obtained by cascade connection.Finally,the circuit is simulated by Spice tool and the output waveforms transform in proper order indicating that the logic function is correct.The energy consumption of the four bits ternary adiabatic Domino counter is 63% less than the conventional Domino counterpart.

  14. Glucagon-like peptide 1 receptor agonist protects high-glucose inducedβcells apoptosis via inhibition of NOX2-dependent ROS production%GLP-1Ra减少高糖诱导的β细胞凋亡作用机制探讨

    Institute of Scientific and Technical Information of China (English)

    丁敏; 李春君; 邢云芝; 于倩; 王鹏华; 于德民

    2015-01-01

    Objective To investigate the possible mechanisms of glucagon-like peptide 1 receptor agonists (GLP-1Ra) protection against hyperglycemic induced beta cell apoptosis through depression of NOX2-dependent ROS production. Methods The rat model of type 2 diabetes (T2DM) was established by injecting small doses of streptozotocin (STZ) fol⁃lowed by 8-week high fat diet. The experimental animals were divided into three groups:normal control (N) group, diabetes (T2DM) group and GLP-1Ra group [treated with liraglutide 200 μg/(kg · d)for 12 weeks]. The blood glucose levels were compared before and after modeling, before treatment and 12-week after treatment with GLP-1Ra. The level of glycosylated hemoglobin (HbA1c) was detected by high-pressure liquid chromatography. Automatic biochemical analyzer was used to de⁃tect levels of aspertate aminotransferase (AST), creatinine (CR) and urea nitrogen (BUN). The apoptotic rates of islets were determined by TUNEL method and cleaved caspase 3 was detected by immunohistochemistry. DCFH-DA fluorescent probe was used to detect reactive oxygen species (ROS) levels of islets. Levels of NADPH oxidase (NOX) catalytic subunit (NOX 2) in islets were measured by immunohistochemistry. Results At the end of the study, glycemic control (average blood glucose/week and HbA1c) and lipid situation were improved significantly in the GLP-1Ra group than those of N group (P0.05). After application Apocynin for inhibition, there were no significant differences between three groups (P>0.05). The level of NOX2 was significantly lower in GLP-1Ra group compared to that of T2DM group (P<0.05). Conclusion GLP-1Ra can inhibit apoptosis ofβcells in diabetes rat, and the depression of NOX2-dependent ROS may be one of the important underly⁃ing mechanisms.%目的:探讨胰高血糖素样肽-1(GLP-1)受体激动剂(GLP-1Ra)减少高糖诱导的β细胞凋亡作用的可能机制。方法正常对照(N,普通饲料喂养)组、2型糖尿病(T2

  15. Counter-Rotating Tandem Motor Drilling System

    Energy Technology Data Exchange (ETDEWEB)

    Kent Perry

    2009-04-30

    Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively compared to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger

  16. Counter-terrorism threat prediction architecture

    Science.gov (United States)

    Lehman, Lynn A.; Krause, Lee S.

    2004-09-01

    This paper will evaluate the feasibility of constructing a system to support intelligence analysts engaged in counter-terrorism. It will discuss the use of emerging techniques to evaluate a large-scale threat data repository (or Infosphere) and comparing analyst developed models to identify and discover potential threat-related activity with a uncertainty metric used to evaluate the threat. This system will also employ the use of psychological (or intent) modeling to incorporate combatant (i.e. terrorist) beliefs and intent. The paper will explore the feasibility of constructing a hetero-hierarchical (a hierarchy of more than one kind or type characterized by loose connection/feedback among elements of the hierarchy) agent based framework or "family of agents" to support "evidence retrieval" defined as combing, or searching the threat data repository and returning information with an uncertainty metric. The counter-terrorism threat prediction architecture will be guided by a series of models, constructed to represent threat operational objectives, potential targets, or terrorist objectives. The approach would compare model representations against information retrieved by the agent family to isolate or identify patterns that match within reasonable measures of proximity. The central areas of discussion will be the construction of an agent framework to search the available threat related information repository, evaluation of results against models that will represent the cultural foundations, mindset, sociology and emotional drive of typical threat combatants (i.e. the mind and objectives of a terrorist), and the development of evaluation techniques to compare result sets with the models representing threat behavior and threat targets. The applicability of concepts surrounding Modeling Field Theory (MFT) will be discussed as the basis of this research into development of proximity measures between the models and result sets and to provide feedback in support of model

  17. COUNTER-PUNISHMENT, COMMUNICATION AND COOPERATION AMONG PARTNERS

    Directory of Open Access Journals (Sweden)

    Giulia eAndrighetto

    2016-04-01

    Full Text Available We study how communication affects cooperation in an experimental public goods environment with punishment and counter-punishment opportunities. Participants interacted over thirty rounds in fixed groups with fixed identifiers that allowed them to trace other group members’ behavior over time. The two dimensions of communication we study are asking for a specific contribution level and having to express oneself when choosing to counter-punish. We conduct four experimental treatments, all involving a contribution stage, a punishment stage and a counter-punishment stage in each round. In the first treatment communication is not possible at any of the stages. The second treatment allows participants to ask for a contribution level at the punishment stage and in the third treatment participants are required to send a message if they decide to counter-punishment. The fourth combines the two communication channels of the second and third treatments. We find that the three treatments involving communication at any of the two relevant stages lead to significantly higher contributions than the baseline treatment. We find no difference between the three treatments with communication. We also relate our results to previous results from treatments without counter-punishment opportunities and do not find that the presence of counter-punishment leads to lower cooperation level. The overall pattern of results shows that given fixed identifiers the key factor is the presence of communication. Whenever communication is possible contributions and earnings are higher than when it is not, regardless of counter-punishment opportunities.

  18. Effect of Counter Electrode in Electroformation of Giant Vesicles

    Directory of Open Access Journals (Sweden)

    Shuuhei Oana

    2011-11-01

    Full Text Available Electroformation of cell-sized lipid membrane vesicles (giant vesicles, GVs, from egg yolk phosphatidylcholine, was examined varying the shape of the counter electrode. Instead of a planar ITO (indium tin oxide electrode commonly used, platinum wire mesh was employed as a counter electrode facing lipid deposit on a planar formation electrode. The modification did not significantly alter GV formation, and many GVs of 30–50 µm, some as large as 100 µm, formed as with the standard setup, indicating that a counter electrode does not have to be a complete plane. When the counter electrode was reduced to a set of two parallel platinum wires, GV formation deteriorated. Some GVs formed, but only in close proximity to the counter electrode. Lower electric voltage with this setup no longer yielded GVs. Instead, a large onion-like multilamellar structure was observed. The deteriorated GV formation and the formation of a multilamellar structure seemed to indicate the weakened effect of the electric field on lipid deposit due to insufficient coverage with a small counter electrode. Irregular membranous objects formed by spontaneous swelling of lipid without electric voltage gradually turned into multilamellar structure upon following application of voltage. No particular enhancement of GV formation was observed when lipid deposit on a wire formation electrode was used in combination with a large planar counter electrode.

  19. A dual-detector extended range rem-counter

    CERN Document Server

    Ferrarini, M; Silari, M; Agosteo, S

    2010-01-01

    The design and characterization of a dual-detector spherical rem counter is discussed in this paper. The rem counter is based on a polythene sphere with lead and cadmium insets, designed to host at its centre either an active (He-3 SP9 proportional counter) or a passive (CR39 + B-10 radiator) thermal neutron detector. Its sensitivity ranges from thermal energies up to 1 GeV. A Monte Carlo characterization of this dual-detector rem counter has shown no significant change in the shape of the response curve obtained with the two detectors. The rem counter has been calibrated with a Pu-Be source. An intercomparison in a high-energy neutron field has been carried out at the CERF facility at CERN among the rem counter in the two configurations, two commercial units and the original version of the active LINUS in use at CERN. Both the active and passive versions of the rem counter agree, within the statistical uncertainties, with the CERN LINUS and with the facility reference values. Both versions of the instrument ...

  20. Particle size dependent response of aerosol counters

    Science.gov (United States)

    Ankilov, A.; Baklanov, A.; Colhoun, M.; Enderle, K.-H.; Gras, J.; Julanov, Yu.; Kaller, D.; Lindner, A.; Lushnikov, A. A.; Mavliev, R.; McGovern, F.; O'Connor, T. C.; Podzimek, J.; Preining, O.; Reischl, G. P.; Rudolf, R.; Sem, G. J.; Szymanski, W. W.; Vrtala, A. E.; Wagner, P. E.; Winklmayr, W.; Zagaynov, V.

    During an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (IAMAS-IUGG), 10 instruments for aerosol number concentration measurement were studied, covering a wide range of methods based on various different measuring principles. In order to investigate the detection limits of the instruments considered with respect to particle size, simultaneous number concentration measurements were performed for monodispersed aerosols with particle sizes ranging from 1.5 to 50 nm diameter and various compositions. The instruments considered show quite different response characteristics, apparently related to the different vapors used in the various counters to enlarge the particles to an optically detectable size. A strong dependence of the 50% cutoff diameter on the particle composition in correlation with the type of vapor used in the specific instrument was found. An enhanced detection efficiency for ultrafine hygroscopic sodium chloride aerosols was observed with water operated systems, an analogous trend was found for n-butanol operated systems with nonhygroscopic silver and tungsten oxide particles.

  1. Training options for countering nuclear smuggling

    Energy Technology Data Exchange (ETDEWEB)

    Ball, D Y; Erickson, S A

    1999-07-01

    The burden of stopping a nuclear smuggling attempt at the border rests most heavily on the front-line customs inspector. He needs to know how to use the technological tools at his disposal, how to discern tell-tale anomalies in export documents and manifests, how to notice psychological signs of a smuggler's tension, and how to search anything that might hide nuclear material. This means that assistance in the counter-nuclear smuggling training of customs officers is one of the most critical areas of help that the United States can provide. This paper discusses the various modes of specialized training, both in the field and in courses, as well as the types of assistance that can be provided. Training for nuclear customs specialists, and supervisors and managers of nuclear smuggling detection systems is also important, and differs from front-line inspector training in several aspects. The limitations of training and technological tools such as expert centers that will overcome these limitations are also discussed. Training assistance planned by DOE/NN-43 to Russia within the Second Line of Defense program is discussed in the light of these options, and future possibilities for such training are projected.

  2. Over-the-Counter Medications in Pregnancy.

    Science.gov (United States)

    Servey, Jessica; Chang, Jennifer

    2014-10-15

    Many pregnant women take over-the-counter (OTC) medications despite the absence of randomized controlled trials to guide their use during pregnancy. Most data come from case-control and cohort studies. In 1979, the U.S. Food and Drug Administration began reviewing all prescription and OTC medications to develop risk categories for use in pregnancy. Most OTC medications taken during pregnancy are for allergy, respiratory, gastrointestinal, or skin conditions, as well as for general analgesia. Acetaminophen, which is used by about 65% of pregnant women, is generally considered safe during any trimester. Cold medications are also commonly used and are considered safe for short-term use outside of the first trimester. Many gastrointestinal medications are now available OTC. Histamine H2 blockers and proton pump inhibitors have not demonstrated significant fetal effects. Nonsteroidal anti-inflammatory drugs are generally not recommended in pregnancy, especially during organogenesis and in the third trimester. There are even fewer data regarding use of individual herbal supplements. Ginger is considered safe and effective for treating nausea in pregnancy. Topical creams are considered safe based on small studies and previous practice. All OTC medication use should be discussed with patients, and the effects of the symptoms should be balanced with the risks and benefits of each medication. Because of the expanding OTC market, formalized studies are warranted for patients to make a safe and informed decision about OTC medication use during pregnancy.

  3. Hardware support for collecting performance counters directly to memory

    Science.gov (United States)

    Gara, Alan; Salapura, Valentina; Wisniewski, Robert W.

    2012-09-25

    Hardware support for collecting performance counters directly to memory, in one aspect, may include a plurality of performance counters operable to collect one or more counts of one or more selected activities. A first storage element may be operable to store an address of a memory location. A second storage element may be operable to store a value indicating whether the hardware should begin copying. A state machine may be operable to detect the value in the second storage element and trigger hardware copying of data in selected one or more of the plurality of performance counters to the memory location whose address is stored in the first storage element.

  4. The Application of Counter-Rotating Turbine in Rocket Turbopump

    Directory of Open Access Journals (Sweden)

    Tang Fei

    2008-01-01

    Full Text Available Counter rotating turbine offers advantages on weight, volume, efficiency, and maneuverability relative to the conventional turbine because of its special architecture. Nowadays, it has been a worldwide research emphasis and has been used widely in the aeronautic field, while its application in the astronautic field is seldom investigated. Researches of counter rotating turbine for rocket turbopump are reviewed in this paper. A primary analysis of a vaneless counter rotating-turbine configuration with rotors of different diameters and rotational speeds is presented. This unconventional configuration meets the requirements of turbopump and may benefit the performance and reliability of rocket engines.

  5. Countering the ‘Natural’ Organizational Self on Social Media

    DEFF Research Database (Denmark)

    Johansen, Trine Susanne

    2017-01-01

    Using narrative as a theoretical and methodological lens, this study explores digital processes of organizational identity construction in the intersection between organization and market.The purpose is to understand the ways in which online interactions produce counter-narratives that contrast......, challenge and contradict organizational self-narration in light of market place skepticism and cynicism. The study identifies three strategies of counter-narrativizing (authenticity, legitimacy and irony) based on juxtaposing pairs of opposites. Moreover, it suggests counter-narration to be a natural...

  6. Development of Laser-Based Handheld Aerosol Particle Counter

    Institute of Scientific and Technical Information of China (English)

    CHEN Chang; LI Hui

    2005-01-01

    The JC-CA300 handheld Aerosol particle counter is designed and developed based on light scattering principle. The JC-CA300 counter is composed of optical sensor, DSP component and microprocessor unit. The hardware architecture is designed in compact style by SMT IC chips. The whole counter weight is less than 2 pounds. With 32K RAM space, the JC-CA300 can store 500 sampling records and support standard printer and communicate with a computer through RS232 interface. Based on experimental results, the main performance of JC-CA300 is better than that of the ARTI'S HHPC-6 instrument.

  7. Current Over-the-Counter Medicine Label: Take a Look

    Science.gov (United States)

    ... This is to help protect consumers against possible criminal tampering. Drug products with tamper-evident packaging have ... Medicines Medicines in My Home (MIMH) Choosing the right over-the-counter medicine (OTCs) The Over-the- ...

  8. Calibration and Monte Carlo modelling of neutron long counters

    CERN Document Server

    Tagziria, H

    2000-01-01

    The Monte Carlo technique has become a very powerful tool in radiation transport as full advantage is taken of enhanced cross-section data, more powerful computers and statistical techniques, together with better characterisation of neutron and photon source spectra. At the National Physical Laboratory, calculations using the Monte Carlo radiation transport code MCNP-4B have been combined with accurate measurements to characterise two long counters routinely used to standardise monoenergetic neutron fields. New and more accurate response function curves have been produced for both long counters. A novel approach using Monte Carlo methods has been developed, validated and used to model the response function of the counters and determine more accurately their effective centres, which have always been difficult to establish experimentally. Calculations and measurements agree well, especially for the De Pangher long counter for which details of the design and constructional material are well known. The sensitivit...

  9. leaves extracts as counter stain in gram staining reaction 56

    African Journals Online (AJOL)

    DR. AMINU

    Keywords: Aqueous Extract, Dyes, Henna, Counter-Staining. INTRODUCTION ... is a stain with color contrasting to the principal stain, making the .... different solutions of ethanol extracts were prepared .... this plant a true natural dye. Saponins ...

  10. Sinus Pain: Can Over-the-Counter Medications Help?

    Science.gov (United States)

    ... requests or policy questions to our media and public relations staff at newsroom@entnet.org . Why Do We ... over-the-counter (OTC) medications. What Is The Role Of OTC Medication For Sinus Pain? There are ...

  11. Over the Counter Laxatives for Constipation: Use with Caution

    Science.gov (United States)

    ... may be best for you. Type of laxative (brand examples) How they work Side effects Oral osmotics ( ... the-counter laxatives. Journal of the American Medical Association. 2014;312:1167. Constipation. National Institute of Diabetes ...

  12. Over-the-counter codeine use in Iceland

    DEFF Research Database (Denmark)

    Almarsdóttir, Anna Birna; Grimsson, A

    2000-01-01

    The objective of this study was to test the assumption that liberalizing community pharmacy ownership in Iceland would lead to increased irrational use of over-the-counter pain relievers containing codeine....

  13. Study Counters Link Between Excess Pregnancy Weight and Overweight Kids

    Science.gov (United States)

    ... Study Counters Link Between Excess Pregnancy Weight and Overweight Kids Connection is likely in the genes, researchers ... 24, 2017 (HealthDay News) -- Kids whose moms were overweight during pregnancy have increased odds of being overweight ...

  14. Bathroom Buddies: Countering your Clockwise Rotation

    Science.gov (United States)

    Cooper, C. M.; Stegman, D. R.

    2006-12-01

    Which way does your bathtub, toilet, sink, or other favorite plumbing basin drain? Popular television shows perpetuate the fact that water spins the opposite direction in the southern hemisphere, and sometimes even explicitly point to the Coriolis effect (or Earth's rotation) as the cause. Skeptics disagree: "No way. Water doesn't obey your rules: it goes where it wants...like me, babe." [1]. Fact: Cyclones rotate clockwise in the southern hemisphere and hurricanes counter-clockwise in the northern hemisphere. But does your hemisphere also determine the direction water spirals down your toilet? In the ideal scenario of water draining out a sink (i.e. a defect-free, perfectly-leveled basin in which water has remained undisturbed for sufficient enough time to quiet any background motions or eddies) --- then yes, maybe it is possible. However, in everyday life, not even the most decadent of bathtubs provide us a large enough lengthscale to observe the Coriolis effect on the direction which water spirals towards the drain. Thus, we are left confronting the possibility that something heard on television isn't true. But is just "telling" students, friends, or strangers in bars enough to debunk this urban myth? Rather, we offer a practical demonstration involving a friend from the opposite hemisphere (if not one in existence, then find one on the internet!), a bathroom, a funnel, a bucket, some food coloring, a camera, a pitcher and some equations and scalings for extra credit and fun. 1) Simpson, B., "Bart vs. Australia", Season 6, Episode 119, 1995.

  15. Evaluation of dual flow counter-current chromatography and intermittent counter-current extraction.

    Science.gov (United States)

    Ignatova, Svetlana; Hewitson, Peter; Mathews, Ben; Sutherland, Ian

    2011-09-09

    The aim of this research is to compare two continuous extraction technologies, intermittent counter-current extraction (ICcE) and dual flow counter-current chromatography (DFCCC), in terms of loading and throughput using the GUESSmix, and show the advantages and disadvantages of the two methods. A model sample containing caffeine, vanillin, naringenin and carvone, with a total load of 11.2 g, was employed with a hexane-ethyl acetate-methanol-water (2:3:2:3) phase system to evaluate an ICcE method on a preparative (912 ml coil volume) DE-Midi instrument. While DFCCC was carried out on a specially designed preparative (561 ml coil volume) bobbin installed in a similar Midi instrument case. While similar throughputs of 7.8 g/h and 6.9 g/h were achieved for the ICcE and DFCCC methods respectively, ICcE was demonstrated to have a number of advantages over DFCCC.

  16. Over-the-counter codeine use in Iceland

    DEFF Research Database (Denmark)

    Almarsdóttir, Anna Birna; Grimsson, A

    2000-01-01

    The objective of this study was to test the assumption that liberalizing community pharmacy ownership in Iceland would lead to increased irrational use of over-the-counter pain relievers containing codeine.......The objective of this study was to test the assumption that liberalizing community pharmacy ownership in Iceland would lead to increased irrational use of over-the-counter pain relievers containing codeine....

  17. Using DMA for copying performance counter data to memory

    Science.gov (United States)

    Gara, Alan; Salapura, Valentina; Wisniewski, Robert W

    2013-12-31

    A device for copying performance counter data includes hardware path that connects a direct memory access (DMA) unit to a plurality of hardware performance counters and a memory device. Software prepares an injection packet for the DMA unit to perform copying, while the software can perform other tasks. In one aspect, the software that prepares the injection packet runs on a processing core other than the core that gathers the hardware performance data.

  18. Over-the-counter treatments for acne and rosacea.

    Science.gov (United States)

    Rosamilia, Lorraine Larsen

    2016-06-01

    Acne and rosacea are common inflammatory processes historically classified in the same disease category, but evolving understanding of their disparate pathophysiology and exacerbating factors have generated an enormous armamentarium of therapeutic possibilities. Patients seek over-the-counter therapies first when managing cutaneous disease; therefore, this review defines ingredients considered to be effective over-the-counter acne and rosacea products, their mechanisms, and safe formulations, including botanical components, oral supplements, and other anecdotal options in this vast skin care domain.

  19. CounterPoint: Zeeman-split absorption lines

    Science.gov (United States)

    Deen, Casey

    2015-12-01

    CounterPoint works in concert with MoogStokes (ascl:1308.018). It applies the Zeeman effect to the atomic lines in the region of study, splitting them into the correct number of Zeeman components and adjusting their relative intensities according to the predictions of Quantum Mechanics, and finally creates a Moog-readable line list for use with MoogStokes. CounterPoint has the ability to use VALD and HITRAN line databases for both atomic and molecular lines.

  20. Liberty and Order: Reintegration as Counter-Insurgency in Colombia

    Science.gov (United States)

    2003-01-01

    experienced the same fits and starts as others in the region. There have been successes , including the reintegration of the M-19 (Movimiento del 19... REINTEGRATION AS COUNTER-INSURGENCY IN COLOMBIA Mr. GREGORY E. PHILLIPS, DOS COURSE 5601 and 5602 FUNDAMENTALS OF STRATEGIC LOGIC and THE NATURE OF...COVERED 00-00-2003 to 00-00-2003 4. TITLE AND SUBTITLE Liberty and Order: Reintegration as Counter-Insurgency in Colombia 5a. CONTRACT NUMBER 5b

  1. Counter-terrorism judicial review by a traditionally weak judiciary

    DEFF Research Database (Denmark)

    Rytter, Jens Elo

    2014-01-01

    The article analyses recent Danish case law on counter-terrorism measures to ascertain the extent to which a tradiitonally weak judiciary like the Danish one performs a real review. The conclusion is that the review is real, but measured.......The article analyses recent Danish case law on counter-terrorism measures to ascertain the extent to which a tradiitonally weak judiciary like the Danish one performs a real review. The conclusion is that the review is real, but measured....

  2. MODELS FOR THE COUNTER-GRADIENT TRANSPORT PHENOMENA

    Institute of Scientific and Technical Information of China (English)

    蒋剑波; 卢志明; 刘晓明; 刘宇陆

    2001-01-01

    The counter gradient transport phenomena on momentum, energy and passive scalar in turbulent flows were studied by use of the single response function for TSDIA. As a result, models that can describe qualitatively the phenomena are obtained. Then the results are simplified by use of the inertial range theory, and the results for lower degrees agree with results of predecessor. Finally the counter gradient-transport phenomena in channel flow and circular wake flow are analyzed.

  3. A Gas Proportional Scintillation Counter with krypton filling

    Science.gov (United States)

    Monteiro, C. M. B.; Mano, R. D. P.; Barata, E. C. G. M.; Fernandes, L. M. P.; Freitas, E. D. C.

    2016-12-01

    A Gas Proportional Scintillation Counter filled with pure krypton was studied. Energy resolution below 10% for 5.9-keV X-rays was obtained with this prototype. This value is much better than the energy resolution obtained with proportional counters or other MPGDs with krypton filling. The krypton electroluminescence scintillation and ionisation thresholds were found to be about 0.5 and 3.5 kV cm-1bar-1, respectively.

  4. Advertising health: the case for counter-ads.

    Science.gov (United States)

    Dorfman, L; Wallack, L

    1993-01-01

    Public service advertisements have been used by many in hopes of "selling" good health behaviors. But selling good behavior--even if it could be done more effectively--is not the best goal for using mass media to prevent health problems. Personal behavior is only part of what determines health status. Social conditions and the physical environment are important determinants of health that are usually ignored by health promotion advertising. Public service advertising may be doing more harm than good if it is diverting attention from more effective socially based health promotion strategies. Counter-ads are one communications strategy that could be used to promote a broader responsibility for rectifying health problems. In the tradition of advocacy advertising directly promoting policy rather than products, counter-ads promote views consistent with a public health perspective. Counter-ads set the agenda for health issues, conferring status on policy-oriented strategies for addressing health problems. The primary purpose of counter-ads is to challenge the dominant view that public health problems reflect personal health habits. They are controversial because they place health issues in a social and political context. Advertising strategies for health promotion range over a spectrum from individually oriented public service advertising to socially oriented counter-advertising. The recent anti-tobacco campaign from the California Department of Health Services represents advertisements across the spectrum. Counter-ads that focus on a politically controversial definition for health problems are an appropriate and necessary alternative to public service advertising.

  5. Message passing with a limited number of DMA byte counters

    Energy Technology Data Exchange (ETDEWEB)

    Blocksome, Michael (Rochester, MN); Chen, Dong (Croton on Hudson, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Kumar, Sameer (White Plains, NY); Parker, Jeffrey J. (Rochester, MN)

    2011-10-04

    A method for passing messages in a parallel computer system constructed as a plurality of compute nodes interconnected as a network where each compute node includes a DMA engine but includes only a limited number of byte counters for tracking a number of bytes that are sent or received by the DMA engine, where the byte counters may be used in shared counter or exclusive counter modes of operation. The method includes using rendezvous protocol, a source compute node deterministically sending a request to send (RTS) message with a single RTS descriptor using an exclusive injection counter to track both the RTS message and message data to be sent in association with the RTS message, to a destination compute node such that the RTS descriptor indicates to the destination compute node that the message data will be adaptively routed to the destination node. Using one DMA FIFO at the source compute node, the RTS descriptors are maintained for rendezvous messages destined for the destination compute node to ensure proper message data ordering thereat. Using a reception counter at a DMA engine, the destination compute node tracks reception of the RTS and associated message data and sends a clear to send (CTS) message to the source node in a rendezvous protocol form of a remote get to accept the RTS message and message data and processing the remote get (CTS) by the source compute node DMA engine to provide the message data to be sent.

  6. Over the counter ophthalmic drug misuse, are we aware?

    Directory of Open Access Journals (Sweden)

    Rajani Kadri

    2010-07-01

    Full Text Available Aim: To investigate the misuse of ‘over the counter’ ophthalmic medications in our city. Method: Responses of a structured questionnaire covering various aspects of over the counter drug use was obtained from pharmacy workers in and around our city. Results: Eighty nine pharmacy workers took part in this cross–sectional study. An average number of seven patients per day with ophthalmic complaints were seen by the pharmacy workers. Dispensing over the counter was practiced by 89.9% of the pharmacists. The most common complaint of the patients visiting the pharmacy, was redness and itching (86.5%. Antibiotics (96.6% were the most common eye drops dispensed over the counter, followed by steroids (55.1%, decongestants (54.1%, antibiotic-steroid combination eye drops (29.2% and lubricants (16.8%. Awareness regarding complications of steroid use was seen in 40.6% of pharmacists. 6.7% pharmacists had seen patients with complications following use of over the counter medications. In our study, majority of the eye drops dispensed were prescription drugs. Conclusion: Availability of prescription eye drops over the counter is an immense public threat. Educating the pharmacist and the population can decrease ocular morbidity. Research into methods to effectively deal with over-the-counter drug misuse is required and law can be enforced based on the findings.

  7. Detailed Network Measurements Using Sparse Graph Counters: The Theory

    CERN Document Server

    Lu, Yi; Prabhakar, Balaji

    2007-01-01

    Measuring network flow sizes is important for tasks like accounting/billing, network forensics and security. Per-flow accounting is considered hard because it requires that many counters be updated at a very high speed; however, the large fast memories needed for storing the counters are prohibitively expensive. Therefore, current approaches aim to obtain approximate flow counts; that is, to detect large elephant flows and then measure their sizes. Recently the authors and their collaborators have developed [1] a novel method for per-flow traffic measurement that is fast, highly memory efficient and accurate. At the core of this method is a novel counter architecture called "counter braids.'' In this paper, we analyze the performance of the counter braid architecture under a Maximum Likelihood (ML) flow size estimation algorithm and show that it is optimal; that is, the number of bits needed to store the size of a flow matches the entropy lower bound. While the ML algorithm is optimal, it is too complex to im...

  8. DMA shared byte counters in a parallel computer

    Science.gov (United States)

    Chen, Dong; Gara, Alan G.; Heidelberger, Philip; Vranas, Pavlos

    2010-04-06

    A parallel computer system is constructed as a network of interconnected compute nodes. Each of the compute nodes includes at least one processor, a memory and a DMA engine. The DMA engine includes a processor interface for interfacing with the at least one processor, DMA logic, a memory interface for interfacing with the memory, a DMA network interface for interfacing with the network, injection and reception byte counters, injection and reception FIFO metadata, and status registers and control registers. The injection FIFOs maintain memory locations of the injection FIFO metadata memory locations including its current head and tail, and the reception FIFOs maintain the reception FIFO metadata memory locations including its current head and tail. The injection byte counters and reception byte counters may be shared between messages.

  9. Measuring Cherenkov Backgrounds from Proportional Counters in SNO

    Science.gov (United States)

    Seibert, Stanley

    2006-04-01

    In the current phase of operation of the Sudbury Neutrino Observatory, He-3 proportional counters have been deployed in the center of the detector to measure neutron production from neutral-current interactions between neutrinos and deuterons in the heavy water. Radioactive decays of Bi-214 and Tl-208 in the counters produce gammas of sufficient energy to photodisintegrate deuterons, which become a background to the neutral current measurement. We have measured the background rate in-situ using Cherenkov light detected with SNO's 9456 inward-looking photomultiplier tubes. A maximum likelihood method is used to separate backgrounds in the heavy water from backgrounds in the proportional counters based upon the spatial distribution of low energy Cherenkov event vertices. Uncertainties on the backgrounds have been estimated using calibration data taken with both a distributed Na-24 source, and a contained Th source deployed at various points in the detector.

  10. Event identification in 3He proportional counters using risetime discrimination

    Science.gov (United States)

    Langford, T. J.; Bass, C. D.; Beise, E. J.; Breuer, H.; Erwin, D. K.; Heimbach, C. R.; Nico, J. S.

    2013-07-01

    We present a straightforward method for particle identification and background rejection in 3He proportional counters for use in neutron detection. By measuring the risetime and pulse height of the preamplifier signals, one may define a region in the risetime versus pulse height space where the events are predominately from neutron interactions. For six proportional counters surveyed in a low-background environment, we demonstrate the ability to reject alpha-particle events with an efficiency of 99%. By applying the same method, we also show an effective rejection of microdischarge noise events that, when passed through a shaping amplifier, are indistinguishable from physical events in the counters. The primary application of this method is in measurements where the signal-to-background for counting neutrons is very low, such as in underground laboratories.

  11. Event Identification in $^3$He Proportional Counters Using Risetime Discrimination

    CERN Document Server

    Langford, T J; Beise, E J; Breuer, H; Erwin, D K; Heimbach, C R; Nico, J S

    2012-01-01

    We present a straightforward method for particle identification and background rejection in $^3$He proportional counters for use in neutron detection. By measuring the risetime and pulse height of the preamplifier signals, one may define a region in the risetime versus pulse height space where the events are predominately from neutron interactions. For six proportional counters surveyed in a low-background environment, we demonstrate the ability to reject alpha-particle events with an efficiency of 99%. By applying the same method, we also show an effective rejection of microdischarge noise events that, when passed through a shaping amplifier, are indistinguishable from physical events in the counters. The primary application of this method is in measurements where the signal-to-background for counting neutrons is very low, such as in underground laboratories.

  12. Wind tunnel tests of stratospheric airship counter rotating propellers

    Directory of Open Access Journals (Sweden)

    Yaxi Chen

    2015-01-01

    Full Text Available Aerodynamic performance of the high-altitude propeller, especially the counter rotation effects, is experimentally studied. Influences of different configurations on a stratospheric airship, included 2-blade counter-rotating propeller (CRP, dual 2-blade single rotation propellers (SRPs and 4-blade SRP, are also indicated. This research indicates that the effect of counter rotation can greatly improve the efficiency. It shows that the CRP configuration results in a higher efficiency than the dual 2-blade SRPs configuration or 4-blade SRP configuration under the same advance ratio, and the CRP configuration also gains the highest efficiency whether under the situation of providing the same trust or absorbing the same power. It concludes that, for a stratospheric airship, the CRP configuration is better than the multiple SRPs configuration or a multi-blade SRP one.

  13. Emergent information technologies and enabling policies for counter-terrorism

    CERN Document Server

    Popp, R

    2006-01-01

    Explores both counter-terrorism and enabling policy dimensions of emerging information technologies in national security After the September 11th attacks, "connecting the dots" has become the watchword for using information and intelligence to protect the United States from future terrorist attacks. Advanced and emerging information technologies offer key assets in confronting a secretive, asymmetric, and networked enemy. Yet, in a free and open society, policies must ensure that these powerful technologies are used responsibly, and that privacy and civil liberties remain protected. Emergent Information Technologies and Enabling Policies for Counter-Terrorism provides a unique, integrated treatment of cutting-edge counter-terrorism technologies and their corresponding policy options. Featuring contributions from nationally recognized authorities and experts, this book brings together a diverse knowledge base for those charged with protecting our nation from terrorist attacks while preserving our civil liberti...

  14. Fast scintillation counters for the D0 muon system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Baldin, B. [Fermi National Accelerator Lab., Batavia, IL (United States); Abramov, V.; Babintsev, V. [and others

    1999-08-01

    The design and main parameters of the completely redesigned D0 Forward Angle Muon System (FAMUS: 1.0 < {vert_bar}{eta}{vert_bar} < 2.0) for the next high luminosity Tevatron Collider run are reported. Results of the studies of trigger scintillation counters based on fast scintillator Bicron 404A and WLS bars SOFZ-105 are presented. The authors report about results of test beam studies of prototype counters including minimum ionizing particles detection efficiency, time resolution and amplitude response. Radiation ageing of scintillating materials for the doses up to 1 Mrad, phototubes magnetic shielding in the fields of up to 700 G and ageing of phototubes are presented. All tests show robustness of scintillation counters as triggering detector of the new muon system for a long period.

  15. Forensic Speaker Recognition Law Enforcement and Counter-Terrorism

    CERN Document Server

    Patil, Hemant

    2012-01-01

    Forensic Speaker Recognition: Law Enforcement and Counter-Terrorism is an anthology of the research findings of 35 speaker recognition experts from around the world. The volume provides a multidimensional view of the complex science involved in determining whether a suspect’s voice truly matches forensic speech samples, collected by law enforcement and counter-terrorism agencies, that are associated with the commission of a terrorist act or other crimes. While addressing such topics as the challenges of forensic case work, handling speech signal degradation, analyzing features of speaker recognition to optimize voice verification system performance, and designing voice applications that meet the practical needs of law enforcement and counter-terrorism agencies, this material all sounds a common theme: how the rigors of forensic utility are demanding new levels of excellence in all aspects of speaker recognition. The contributors are among the most eminent scientists in speech engineering and signal process...

  16. Radiosonde aerosol counter for vertical profiling of atmospheric dust layers

    Science.gov (United States)

    Ulanowski, Z.; Hirst, E.; Kaye, P. H.; Harrison, R. G.; Nicoll, K. A.; Rogers, G.

    2010-05-01

    A low-cost, miniature aerosol particle counter has been developed, intended for use with balloon-borne meteorological radiosondes. It is particularly suitable for airborne mineral dust measurements. Ambient air is drawn into the counter using a diaphragm pump at a rate of 0.5 litre per minute. The counter detects particles in the airstream using a diode laser and a photodiode. Output from the photodiode is digitised into 5 size bins, with minimum particle diameters equivalent to 0.6, 1.4, 2.6, 5.4 and 10.6 micrometers. The counter is interfaced to a Vaisala RS92 radiosonde, which transmits data from the counter together with meteorological parameters and GPS-derived position to a ground based receiver at 1 Hz rate. Statistically significant particle size distributions can be obtained once a second for number concentrations down to about 100,000 particle per litre (within the measured size range), or correspondingly less at lower temporal resolutions. At the same time, the counter is capable of measuring dust number concentrations exceeding a million per litre without incurring significant errors. Soundings during the DREAME campaign in Kuwait (Ulanowski et al. EGU 2010, AS4.7) and on Cape Verde Islands (Nicoll et al. EGU 2010, AS4.7) provided dust concentration profiles with a typical vertical resolution of 4 m. Comparisons with integrated dust column size distribution measurements from AERONET sun photometers showed good agreement in two out of three cases where near-simultaneous retrievals were available. Optical thickness calculations based on the size distributions measured in Kuwait, with the assumption that the dust particles were prolate spheroids, agreed with the AERONET optical thickness at 675 nm to within 15%.

  17. Full simulation of the Sudbury Neutrino Observatory proportional counters

    Energy Technology Data Exchange (ETDEWEB)

    Beltran, B; Habib, S; Hallin, A L [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada); Bichsel, H; Cox, G A; Formaggio, J A; McGee, S; Miller, M L; Oblath, N S [Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, WA 98195 (United States); Cai, B; Kraus, C; Leslie, H R; Martin, R [Department of Physics, Queen' s University, Kingston, Ontario K7L 3N6 (Canada); Deng, H [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104-6396 (United States); Detwiler, J; Loach, J C [Institute for Nuclear and Particle Astrophysics and Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Hime, A [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Huang, M [Department of Physics, University of Texas at Austin, Austin, TX 78712-0264 (United States); Monreal, B; Monroe, J, E-mail: nsoblath@mit.edu [Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2011-07-15

    The third phase of the Sudbury Neutrino Observatory (SNO) experiment added an array of {sup 3}He proportional counters to the detector. The purpose of this neutral-current detection (NCD) array was to observe neutrons resulting from neutral-current solar-neutrino-deuteron interactions. We have developed a detailed simulation of current pulses from NCD array proportional counters, from the primary neutron capture on {sup 3}He through NCD array signal-processing electronics. This NCD array MC simulation was used to model the alpha-decay background in SNO's third-phase {sup 8}B solar-neutrino measurement.

  18. Full simulation of the Sudbury Neutrino Observatory proportional counters

    CERN Document Server

    Beltran, B; Cai, B.; Cox, G.A.; Deng, H.; Detwiler, J.; Formaggio, J.A.; Habib, S.; Hallin, A.L.; Hime, A.; Huang, M.; Kraus, C.; Leslie, H.R.; Loach, J.C.; Martin, R.; McGee, S.; Miller, M.L.; Monreal, B.; Monroe, J.; Oblath, N.S.; Peeters, S.J.M.; Poon, A.W.P.; Prior, G.; Rielage, K.; Robertson, R.G.H.; Smith, M.W.E.; Stonehill, L.C.; Tolich, N.; Van Wechel, T.; Wan Chan Tseung, H.; Wendland, J.; Wilkerson, J.F.; Wright, A.

    2011-01-01

    The third phase of the Sudbury Neutrino Observatory (SNO) experiment added an array of 3He proportional counters to the detector. The purpose of this Neutral Current Detection (NCD) array was to observe neutrons resulting from neutral-current solar neutrino-deuteron interactions. We have developed a detailed simulation of the current pulses from the NCD array proportional counters, from the primary neutron capture on 3He through the NCD array signal-processing electronics. This NCD array Monte Carlo simulation was used to model the alpha-decay background in SNO's third-phase 8B solar-neutrino measurement.

  19. Semi-automatic, octave-spanning optical frequency counter.

    Science.gov (United States)

    Liu, Tze-An; Shu, Ren-Huei; Peng, Jin-Long

    2008-07-07

    This work presents and demonstrates a semi-automatic optical frequency counter with octave-spanning counting capability using two fiber laser combs operated at different repetition rates. Monochromators are utilized to provide an approximate frequency of the laser under measurement to determine the mode number difference between the two laser combs. The exact mode number of the beating comb line is obtained from the mode number difference and the measured beat frequencies. The entire measurement process, except the frequency stabilization of the laser combs and the optimization of the beat signal-to-noise ratio, is controlled by a computer running a semi-automatic optical frequency counter.

  20. Introduction to Neutron Coincidence Counter Design Based on Boron-10

    Energy Technology Data Exchange (ETDEWEB)

    Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T.; Siciliano, Edward R.

    2012-01-22

    The Department of Energy Office of Nonproliferation Policy (NA-241) is supporting the project 'Coincidence Counting With Boron-Based Alternative Neutron Detection Technology' at Pacific Northwest National Laboratory (PNNL) for development of an alternative neutron coincidence counter. The goal of this project is ultimately to design, build and demonstrate a boron-lined proportional tube based alternative system in the configuration of a coincidence counter. This report, providing background information for this project, is the deliverable under Task 1 of the project.

  1. Counter-propagating patterns in the BioPhotonics Workstation

    DEFF Research Database (Denmark)

    Palima, Darwin; Lindballe, T.; Kristensen, M.V.

    2010-01-01

    for stable three-dimensional manipulation of multiple particles. In this work, we analyze counter-propagating shaped-beam traps that depart from this conventional geometry. We show that projecting shaped beams with separation distances previously considered axially unstable can, in fact, enhance the trap...... by improving axial and transverse trapping stiffness. We also show interesting results of trapping and micromanipulation experiments that combine optical forces with fluidic forces. These results hint about the rich potential of using patterned counter-propagating beams for optical trapping and manipulation...

  2. Address Counter Generators for Low Power Memory BIST

    OpenAIRE

    Balwinder Singh; Sukhleen Bindra Narang; Arun Khosla

    2011-01-01

    In today's Integrated Circuits (IC's) designs Built-in Self Test (BIST) is becoming important for the memory which is the most necessary part of the System on Chip. The March algorithm has been widely used to test memory core of System on chip (SOC). LFSRs and counters are mainly used to generate the memory addresses, which can be serially applied to the memory cores under test. In this paper Address counters and Data generators (i.e. parts of the MBIST) are designed. These implemented in Har...

  3. Search for an optimum time response of spark counters

    CERN Document Server

    Devismes, A; Kress, T; Gobbi, A; Eschke, J; Herrmann, N; Hildenbrand, K D; Koczón, P; Petrovici, M

    2002-01-01

    A spark counter of the type developed by Pestov has been tested with the aim of searching for an optimum time response function, changing voltage, content of noble and quencher gases, pressure and energy-loss. Replacing the usual argon by neon has brought an improvement of the resolution and a significant reduction of tails in the time response function. It has been proven that a counter as long as 90 cm can deliver, using neon gas mixture, a time resolution sigma<60 ps with about 1% absolute tail and an efficiency of about 90%.

  4. GAMMA PROPORTIONAL COUNTER CONTAINING HIGH Z GAS AND LOW Z MODERATOR

    Science.gov (United States)

    Fox, R.

    1963-07-23

    A gamma radiation counter employing a gas proportional counter is described. The radiation counter comprises a cylindrical gas proportional counter which contains a high atomic number gas and is surrounded by a low atomic number gamma radiation moderator material. At least one slit is provided in the moderator to allow accident gamma radiation to enter the moderator in the most favorable manner for moderation, and also to allow low energy gamma radiation to enter the counter without the necessity of passing through the moderator. This radiation counter is capable of detecting and measuring gamma radiation in the energy range of 0.5-5 Mev. (AEC)

  5. Countering Children's Sugared Food Commercials: Do Rebuttals Help?

    Science.gov (United States)

    Kaufman, Lois; Sandman, Peter M.

    To assist the Federal Trade Commission (FTC) in policy making decisions concerning sugared food advertisements on television, a study was conducted to assess the effects on children of counter advertisements and disclaimers as a means of lessening the undesirable impact of sugared food ads. Approximately 1,200 children, aged 5 to 10 years,…

  6. Improving SHA-1 counter-cryptanalysis using unavoidable conditions

    NARCIS (Netherlands)

    Shumow, D.; Stevens, M.M.J.

    2015-01-01

    The concept of counter-cryptanalysis and a collision detection algorithm that detects whether a given single message was constructed using a cryptanalytic collision attack on MD5 or SHA-1 was presented by Stevens at CRYPTO 2013. It was shown that collision detection is not only possible but also pra

  7. Stellar counter-rotation in lenticular galaxy NGC 448

    CERN Document Server

    Katkov, Ivan Yu; Chilingarian, Igor V; Uklein, Roman I; Egorov, Oleg V

    2016-01-01

    The counter-rotation phenomenon in disc galaxies directly indicates a complex galaxy assembly history which is crucial for our understanding of galaxy physics. Here we present the complex data analysis for a lenticular galaxy NGC 448, which has been recently suspected to host a counter-rotating stellar component. We collected deep long-slit spectroscopic observations using the Russian 6-m telescope and performed the photometric decomposition of Sloan Digital Sky Survey (SDSS) archival images. We exploited (i) a non-parametric approach in order to recover stellar line-of-sight velocity distributions and (ii) a parametric spectral decomposition technique in order to disentangle stellar population properties of both main and counter-rotating stellar discs. Our spectral decomposition stays in perfect agreement with the photometric analysis. The counter-rotating component contributes $\\approx$30 per cent to the total galaxy light. We estimated its stellar mass to be $9.0^{+2.7}_{-1.8}\\cdot10^{9}M_\\odot$. The radia...

  8. Crypto and empire: the contradictions of counter-surveillance advocacy

    NARCIS (Netherlands)

    Gürses, S.; Kundnani, A.; Van Hoboken, J.

    2016-01-01

    Since Edward Snowden’s revelations of US and UK surveillance programs, privacy advocates, progressive security engineers, and policy makers have been seeking to win majority support for countering surveillance. The problem is framed as the replacement of targeted surveillance with mass surveillance

  9. BABYSCAN - a whole body counter for small children in Fukushima

    CERN Document Server

    Hayano, Ryugo S; Bronson, Frazier L; Oginni, Babatunde; Muramatsu, Isamu

    2014-01-01

    BABYSCAN, a whole body counter for small children with a detection limit for $^{137}$Cs of better than 50 Bq/body, was developed, and the first unit has been installed at a hospital in Fukushima, to help families with small children who are very much concerned about internal exposures. The design principles, implementation details and the initial operating experience are described.

  10. [Health care consumers about over-the-counter drugs

    NARCIS (Netherlands)

    Burger, D.M.

    2014-01-01

    Dutch consumers can now purchase 'over-the-counter drugs' (OTCs) at three distribution channels: (a) the pharmacy; (b) the chemist; (c) other sales outlets such as supermarkets and petrol stations. However, little is known about whether consumers consider themselves and others to have adequate knowl

  11. Laser phase-detector and counter for fine displacement measurement

    Science.gov (United States)

    Row, R. T.; Wang, C. P.

    A simple technique for the measurement of fine displacement has been developed. With use of an HeNe laser, an optical phase-detector, and counter, a displacement accuracy of 300 nm has been demonstrated over a range of 2 cm.

  12. Reactance and Coping Responses to Tobacco Counter-Advertisements.

    Science.gov (United States)

    Wehbe, Michelle S; Basil, Michael; Basil, Debra

    2017-07-01

    Tobacco prevention messages generally take one of three tactics: They can be educational, attack the tobacco industry, or attack particular brands. Being a smoker and smoking a particular brand may form an essential part of a person's self-identity. As such, reactance theory suggests that attack messages can unintentionally attack smokers' self-image. A 2 × 2 × 2 × 2 experiment using six different messages and 260 respondents tested whether smokers have different reactions to tobacco counter-advertisements than nonsmokers. It also examined whether attacking a smoker's brand leads to greater reactance and other maladaptive responses compared to attacking other brands. Consistent with predictions, smokers reported more maladaptive coping responses and fewer adaptive coping responses to tobacco counter-ads than nonsmokers. The study also reveals differences attributable to brand identification. These findings suggest that interventions should consider different counter-advertising tactics for smokers and nonsmokers. Similar admonitions may apply to counter-advertising strategies on other health issues.

  13. Development of proportional counters using photosensitive gases and liquids

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.F.

    1984-10-01

    An introduction to the history and to the principle of operation of wire chambers using photosensitive gases and liquids is presented. Their use as light sensors coupled to Gas Scintillation Proportional Counters and BaF/sub 2/, as well as their use in Cherenkov Ring imaging, is discussed in some detail. 42 references, 21 figures.

  14. A Simulation of Counter-Cyclical Intervention: Some Practical Lessons

    Science.gov (United States)

    Grawe, Nathan D.; Watts, Michael, Ed.

    2007-01-01

    The author introduces a simulation of counter-cyclical interventions that highlights important issues surrounding the practice of government intervention. The simulation provides experiential insight as to why economists have long debated the degree of persistence exhibited by disequilibrating shocks and connects this debate to discussions about…

  15. Insubordinate Spaces for Intemperate Times: Countering the Pedagogies of Neoliberalism

    Science.gov (United States)

    Tomlinson, Barbara; Lipsitz, George

    2013-01-01

    Henry A. Giroux argues that countering the disasters of neoliberalism requires facing "the challenge of developing a politics and pedagogy that can serve and actualize a democratic notion of the social" (2011). The authors suggest that Immanuel Wallerstein's notion of "middle-run" temporality (2008) and Stuart Hall's discussion of "middle-level"…

  16. Shift-register coincidence electronics system for thermal neutron counters

    Energy Technology Data Exchange (ETDEWEB)

    Swansen, J.E.; Collinsworth, P.R.; Krick, M.S.

    1980-04-01

    An improved shift-register, coincidence-counting logic circuit, developed for use with thermal neutron well counters, is described in detail. A distinguishing feature of the circuit is its ability to operate usefully at neutron counting rates of several hundred kHz. A portable electronics package incorporating the new coincidence logic and support circuits is also described.

  17. Insubordinate Spaces for Intemperate Times: Countering the Pedagogies of Neoliberalism

    Science.gov (United States)

    Tomlinson, Barbara; Lipsitz, George

    2013-01-01

    Henry A. Giroux argues that countering the disasters of neoliberalism requires facing "the challenge of developing a politics and pedagogy that can serve and actualize a democratic notion of the social" (2011). The authors suggest that Immanuel Wallerstein's notion of "middle-run" temporality (2008) and Stuart Hall's discussion of "middle-level"…

  18. Rapid Scan Humidified Growth Cloud Condensation Nuclei Counter

    Energy Technology Data Exchange (ETDEWEB)

    Gregory L. Kok; Athanasios Nenes

    2013-03-13

    This research focused on enhancements to the streamwise thermal gradient cloud condensation nuclei counter to support the rapid scan mode and to enhance the capability for aerosol humidified growth measurements. The research identified the needs for flow system modifications and range of capability for operating the conventional instrument in the rapid scan and humidified growth modes.

  19. Radiation-hard polycrystalline mercuric iodide semiconductor particle counters

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, M. [Hebrew Univ., Jerusalem (Israel)]|[Sandia National Laboratories, Livermore Ca 94556 (United States); Zuck, A.; Melekhov, L.; Nissenbaum, J. [Hebrew Univ., Jerusalem (Israel); Turchetta, R.; Dulinski, W.; Husson, D.; Riester, J.L. [LEPSI (ULP/IN2P3), Strasbourg (France)

    1998-06-01

    Mercuric iodide polycrystalline radiation detectors, which can act as nuclear particle counters and for large area imaging devices, have been fabricated using three different methods. Response to X- and gamma rays, beta particles and to 100GeV muons, as well as radiation hardness results are briefly described. (orig.) 8 refs.

  20. Counter-intuitive Cases of Data Fusion in Information Retrieval.

    Science.gov (United States)

    Ibraev, Ulukbek; Kantor, Paul; Ng, K. B.

    2001-01-01

    Aspects of Data Fusion (DF) for information retrieval are explored. Based on a geometrical model of DF, it is shown that in the ideal case, performance of DF for a pair of information retrieval schemes may be approximated by a quadratic polynomial. Compares counter-intuitive cases of DF with cases that behave according to the geometric model. (AEF)

  1. Counter-term for the Palatini action of general relativity

    CERN Document Server

    Wang, Jingbo

    2016-01-01

    In this paper, we analysis the counter-term for the general relativity in the Palatini framework. The expression is valid for both the null boundary and non-null boundary. We show that final results coincide with that in Ref.\\cite{pad1} which starts form the Einstein-Hilbert action.

  2. Counter Rotating Open Rotor Animation using Particle Image Velocimetry

    CERN Document Server

    Roosenboom, E W M; Geisler, R; Pallek, D; Agocs, J; Neitzke, K -P

    2011-01-01

    This article describes the two accompanying fluid dynamics videos for the "Counter rotating open rotor flow field investigation using stereoscopic Particle Image Velocimetry" presented at the 64th Annual Meeting of the APS Division of Fluid Dynamics in Baltimore, Maryland, November 20-22, 2011.

  3. Over-the-counter codeine use in Iceland

    DEFF Research Database (Denmark)

    Almarsdóttir, A B; Grimsson, A

    2000-01-01

    BACKGROUND: The objective of this study was to test the assumption that liberalizing community pharmacy ownership in Iceland would lead to increased irrational use of over-the-counter pain relievers containing codeine. METHODS: Based on this assumption we built and tested a model using an interru...

  4. Slim by Design: Kitchen Counter Correlates of Obesity

    Science.gov (United States)

    Wansink, Brian; Hanks, Andrew S.; Kaipainen, Kirsikka

    2016-01-01

    Background: The home is one place where people can control what foods are available and how the environment is arranged. Given the impact of environments on health, the objective of this study is to determine whether the presence of foods on a person's kitchen counter are associated with their body mass index (BMI). Method: In Study 1, a…

  5. Are international fund flows pro- or counter-cyclical?

    NARCIS (Netherlands)

    Li, Suxiao; de Haan, Jakob; Scholtens, Bert; Yang, Haizhen

    2015-01-01

    We investigate whether international fund flows are pro-or counter-cyclical by employing a concordance index. International fund flows are investments in bond and equity markets by institutional investors, such as mutual funds, exchange traded funds, closed-end funds and hedge funds. We find that fu

  6. Antioxidant Micronutrients: Therapeutic Counter Measures for Chemical Agents

    Science.gov (United States)

    2011-03-01

    ANSI Std. Z39.18 W81XWH-08-2-0007 1 Mar 2010 - 28 Feb 2011Annual01-03-2011 Antioxidant Micronutrients : Therapeutic Counter Measures for Chemical...Agents Kedar Prasad, Ph.D. Premier Micronutrient Corporation Novato, CA 94949 The results of the first phase of HD study suggested that exposure to

  7. Intercomparison of number concentration measurements by various aerosol particle counters

    Science.gov (United States)

    Ankilov, A.; Baklanov, A.; Colhoun, M.; Enderle, K.-H.; Gras, J.; Julanov, Yu.; Kaller, D.; Lindner, A.; Lushnikov, A. A.; Mavliev, R.; McGovern, F.; Mirme, A.; O'Connor, T. C.; Podzimek, J.; Preining, O.; Reischl, G. P.; Rudolf, R.; Sem, G. J.; Szymanski, W. W.; Tamm, E.; Vrtala, A. E.; Wagner, P. E.; Winklmayr, W.; Zagaynov, V.

    Total aerosol particle number concentrations, as measured by means of 16 different measurement systems, have been quantitatively compared during an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (ICCP-IUGG). The range of measuring instruments includes Pollak counters (PCO) in use already for several decades, presently available commercial particle counters, as well as laboratory prototypes. The operation of the instruments considered was based on different measurement principles: (1) adiabatic expansion condensation particle counter, (2) flow diffusion condensation particle counter, (3) turbulent mixing condensation particle counter, (4) laser optical particle counter, and (5) electrostatic particle measurement system. Well-defined test aerosols with various chemical compositions were considered: DEHS, sodium chloride, silver, hydrocarbons, and tungsten oxide. The test aerosols were nearly monodispersed with mean particle diameters between 4 and 520 nm, the particle number concentrations were varied over a range from about 4×10 1 to 7×10 6 cm -3. A few measurements were performed with two-component aerosol mixtures. For simultaneous concentration measurements, the various instruments considered were operated under steady state conditions in a linear flow system. A series of at least 10 single concentration measurements was performed by each individual instrument at each set of test aerosol parameters. The average of the concentration data measured by the various instruments was defined as a common reference. The number concentrations obtained from the various instruments typically agreed within a factor of about two over the entire concentration range considered. The agreement of the measured concentrations is notable considering the various different measurement principles applied in this study, and particularly in view of the

  8. Solidarity and Recognition: Geographies of Counter-globalism

    Directory of Open Access Journals (Sweden)

    James Goodman

    2006-01-01

    Full Text Available Globalism is a contested concept, but perhaps best understood as a spatial strategy, which disempowers those unable to transcend the fixity of place and social context. Under globalism fluidity becomes a key source of power, enabling the powerful to liquefy assets, to disembed, and thereby displace, political, social or ecological impacts. The infrastructures of globalism enable the disembodied extension of power across territory, to the extent that one model, universally applicable for all societies, is positioned as supreme. The only possible challenge to globalism perhaps, is through a similarly disembedded counter-movement, that mirrors the global reach and power of mainstream globalism. The praxis of counter-globalist movements suggests a different tendency, one that centres on the assertion of particularity against universality. Expressed in the legitimacy of ‘many worlds’ against ‘one world’ globalism, such resistance centres on exposing the material effects and foregrounding concrete and material experiences of globalism. Movements mobilise against the disembodied logic of globalism on the basis of co-presence and inter-subjectivity, and are embedded in relational concepts of selfhood. They are often intensely embodied and are radically emplaced through militant localism and trans-local dialogue. Counter-globalism thus does not seek to defeat geography; rather it embraces it, as the starting-point of mobilisation. The starting point of this article is thus to analyse globalism as a spatial strategy, a strategy of displacement grounded in material power. Globalism thus signifies the capacity to exploit and dominate at distance, from the sanctity of corporate boardrooms, military briefings and media cutting rooms. The claim is to universal market, military and normative power, but the impact is of extended and deepened division. Centres of power appear more as islands, or enclaves, defined against the backwash effects of counter

  9. Replacement between conformity and counter-conformity in consumption decisions.

    Science.gov (United States)

    Chou, Ting-Jui; Chang, En-Chung; Dai, Qi; Wong, Veronica

    2013-02-01

    This study assessed, in a Chinese context, how self-esteem interacts with perceived similarity and uniqueness to yield cognitive dissonance, and whether the dissonance leads to self-reported conformity or counter-conformity behavior. Participants were 408 respondents from 4 major Chinese cities (M age = 33.0 yr., SD = 4.3; 48% men). Self-perceptions of uniqueness, similarity, cognitive dissonance, self-esteem and need to behave in conformity or counter-conformity were measured. A theoretical model was assessed in four situations, relating the ratings of self-esteem and perceived similarity/uniqueness to the way other people at a wedding were dressed, and the resultant cognitive dissonance and conformity/ counter-conformity behavior. Regardless of high or low self-esteem, all participants reported cognitive dissonance when they were told that they were dressed extremely similarly to or extremely differently from the other people attending the wedding. However, the conforming/counter-conforming strategies used by participants to resolve the cognitive dissonance differed. When encountering dissonance induced by the perceived extreme uniqueness of dress, participants with low self-esteem tended to say they would dress next time so as to conform with the way others were dressed, while those with high self-esteem indicated they would continue their counter-conformity in attire. When encountering dissonance induced by the perceived extreme similarity to others, both those with high and low self-esteem tended to say they would dress in an unorthodox manner to surprise other people in the future.

  10. People's practices: Exploring contestation, counter-development, and rural livelihoods. Cases from Muktinagar, Bangladesh

    NARCIS (Netherlands)

    Huq, H.

    2000-01-01

    People's Practices: Exploring contestation, Counter - development, and rural livelihoodsThe central problems explored in the thesis concern the vulnerability of disadvantaged local people, especially women, and their agency; development discourses and counter-development processes; livelihood strate

  11. HOW THE WAR WAS ‘ONE’: COUNTERING VIOLENT EXTREMISM AND THE SOCIAL DIMENSIONS OF COUNTER-TERRORISM IN CANADA.

    Directory of Open Access Journals (Sweden)

    Tami Amanda Jacoby

    2016-03-01

    Full Text Available The current global “war on terror” highlights a fundamental quandary for all liberal democracies seeking to counter the violent extremism of their own citizens while maintaining civic rights and freedoms. This challenge accompanies a transformation in international conflict from inter-state war and superpower rivalry, to homegrown terrorism, radicalization-to-violence, Internet propaganda, and targeting and recruitment of vulnerable persons. These new threats shift the battlefield, as traditionally defined, to the home front, as extremist violence is nurtured by and perpetrated within public spaces, such as schools, places of religious worship, civil society and the home. Today, violence emanates from within liberal democratic society and its extremist motivations bypass the very institutions that would otherwise support civic rights, freedoms and multiculturalism. As such, attempts to counter extremist violence must appeal to the political, social, cultural, religious and familial aspects of human behavior alongside a parallel shift in efforts to keep citizens safe within their own social spaces. In recent years, Canada has been introduced to home grown and lone individual terrorism with the cases of attack against armed forces personnel in Saint-Jean-sur-Richelieu and Ottawa in 2014. This article identifies the social dimensions of counter-terrorism in the Canadian context, a propitious case by which to evaluate different approaches to countering violent extremism. Canadian initiatives - simultaneously proliferating and in their infancy – raise a host of questions about counter-terrorism in liberal democratic countries. For example, why do individuals radicalize-to-violence in rights-based and multicultural societies? How and when can the liberal democratic state best temper the radicalization process in ways that are effective and procedurally just? What state-society balance works best to counter radicalized viewpoints? Who are the

  12. Nox2-dependent ROS signaling protects against skeletal ageing

    Science.gov (United States)

    Bone remodeling is age-dependently regulated and changes dramatically during the course of development. Progressive accumulation of reactive oxygen species (ROS), including superoxide, hydrogen peroxide, and hydroxyl radicals, has been suspected to be the leading cause of many inflammatory and degen...

  13. Influence of higher valent ions on flexible polyelectrolyte stiffness and counter-ion distribution.

    Science.gov (United States)

    Chremos, Alexandros; Douglas, Jack F

    2016-04-28

    We investigate the influence of counter-ion valency on the flexibility of highly charged flexible polymer chains using molecular dynamics simulations that include both salt and an explicit solvent. As observed experimentally, we find that divalent counter-ions greatly reduce the chain persistence length, lp, in comparison with monovalent counter-ions. On the other hand, polyelectrolyte chains having trivalent counter-ions adopt a much more compact conformation than polyelectrolytes having monovalent and divalent counter-ions. We demonstrate that the tendency of polyelectrolyte chains to become deformed by proximal high valence counter-ions is due to chain "coiling" around the counter-ions. In particular, we find that the number of contacts that the proximal counter-ions have with the polyelectrolyte dictates the extent of chain coiling. This ion-binding induced coiling mechanism influences not only the conformational properties of the polyelectrolyte, but also the counter-ion distribution around the chain. Specifically, we find that higher valent counter-ions lead both to a counter-ion enrichment in close proximity to the polyelectrolyte and to a significant reduction in the spatial extent of the diffuse counter-ion cloud around the polyelectrolyte.

  14. Laboratory Evaluation of Light Obscuration Particle Counters used to Establish use Limits for Aviation Fuel

    Science.gov (United States)

    2015-12-01

    5000 DISTRIBUTION A. Approved for public release: distribution unlimited. Laboratory Evaluation of Light Obscuration Particle Counters used to...To) 4. TITLE AND SUBTITLE Laboratory Evaluation of Light Obscuration Particle Counters used to Establish use Limits for Aviation Fuel 5a. CONTRACT...laboratory evaluations of automatic light obscuration particle counters to develop limits for aviation fuel cleanliness. The laboratory evaluations

  15. Chemical abundances of cosmic rays greater than 4.5 GV measured with a large area proportional counter-scintillation counter stack

    Science.gov (United States)

    Lheureux, J.; Fan, C. Y.; Mainardi, R.; Gloeckler, G.

    1974-01-01

    A 6500 sq cm-ster cosmic-ray detector consisting of 12 gas counter trays sandwiched between two large-area circular scintillation counters was flown from Palestine, Texas in November 1972 to study the composition of primary particles greater than 1.5 GeV/nucleon in the charge range from 3 to 30. For each analyzed event, the particle trajectory was recorded, using four 20-wire proportional counter trays. Also recorded were the energy loss in each of the solid counters and the dE/dx losses in each of the 12 gas counters. The large dynamic range of the detector is established by operating six of the gas counters in the ionization mode. A description of the instrument and some preliminary results are given.

  16. COUNTERING RADICALISATION ACROSS EUROPE – THE PIONEERING ISDEP PROJECT

    Directory of Open Access Journals (Sweden)

    Rozila Kana

    2015-12-01

    Full Text Available The changing landscape of the global terrorism threat coupled with increasing concern about home grown extremism means that the need to tackle the root causes of radicalisation across the European Union has never been greater. The pathway to violent extremism and terrorism is, however, undeniably complex. Frontline practitioners working with those vulnerable to radicalisation need to have the right tools to allow them to recognise, respond to and challenge ideologies and narratives associated with any form of terrorism. A pioneering EU Commission funded project is the first of its kind designed to offer consistency around, and increase awareness of, counter radicalisation specifically for frontline practitioners. Improving Security by Democratic Participation (ISDEP is a two year programme based on the EU Commission’s Prevent strand of the Counter Terrorism Strategy. Training themes focus on helping practitioners to identify the influences and vulnerabilities that shape an individual’s thought processes towards violent extremism.

  17. Measurements of electron attachment by oxygen molecule in proportional counter

    Science.gov (United States)

    Tosaki, M.; Kawano, T.; Isozumi, Y.

    2013-11-01

    We present pulse height measurements for 5-keV Auger electrons from a radioactive 55Fe source mounted at the inner cathode surface of cylindrical proportional counter, which is operated with CH4 admixed dry air or N2. A clear shift of the pulse height has been observed by varying the amount of the admixtures; the number of electrons, created in the primary ionization by Auger electrons, is decreased by the electron attachment of the admixtures during their drift from the place near the source to the anode wire. The large gas amplification (typically 104) in the secondary ionization of proportional counter makes it possible to investigate a small change in the number of primary electrons. The electron attenuation cross-section of O2 has been evaluated by analyzing the shifts of the pulse height caused by the electron attachment to dry air and N2.

  18. Measurements of electron attachment by oxygen molecule in proportional counter

    Energy Technology Data Exchange (ETDEWEB)

    Tosaki, M., E-mail: tosaki.mitsuo.3v@kyoto-u.ac.jp [Radioisotope Research Center, Kyoto University, Kyoto 606-8501 (Japan); Kawano, T. [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292 (Japan); Isozumi, Y. [Radioisotope Research Center, Kyoto University, Kyoto 606-8501 (Japan)

    2013-11-15

    We present pulse height measurements for 5-keV Auger electrons from a radioactive {sup 55}Fe source mounted at the inner cathode surface of cylindrical proportional counter, which is operated with CH{sub 4} admixed dry air or N{sub 2}. A clear shift of the pulse height has been observed by varying the amount of the admixtures; the number of electrons, created in the primary ionization by Auger electrons, is decreased by the electron attachment of the admixtures during their drift from the place near the source to the anode wire. The large gas amplification (typically 10{sup 4}) in the secondary ionization of proportional counter makes it possible to investigate a small change in the number of primary electrons. The electron attenuation cross-section of O{sub 2} has been evaluated by analyzing the shifts of the pulse height caused by the electron attachment to dry air and N{sub 2}.

  19. Effectiveness of Counter-Trafficking Response in Albania

    Directory of Open Access Journals (Sweden)

    Meçe Merita H.

    2016-07-01

    Full Text Available Human trafficking is a new phenomenon of Albanian post-socialist society which significantly increased during the difficult years of its transformation from centralized state-led economy to market economy. Both economic and political instability contributed to its size, nature and multiple dynamics. Drawing on a rights-based approach to human trafficking, this paper examines the effectiveness of the counter-trafficking response of the Albanian government with a special emphasis on prevention, protection and prosecution. Using secondary data and reviewing various country strategic documents, it highlights a range of weaknesses and challenges which have hindered its effectiveness over years. It concludes that successful and effective counter-trafficking response requires well rounded and coordinated gender sensitive, victim-centred, holistic and human rights-based efforts. Combined with adequate law enforcement, they will sustainably tackle the full spectrum of this problem.

  20. Social Appropriateness in EU Counter-Terrorism Law and Policy

    DEFF Research Database (Denmark)

    Martins, Bruno Oliveira

    2015-01-01

    institutions such as the European Parliament or the Court of Justice of the EU. In this chapter it is argued that the constitutional foundations of the EU play a decisive role in granting legitimacy to EU counter-terrorism law and policy and to ensuring its social acceptability. Combining sociological...... institutionalist theory with insights from the New Haven school, namely its societal and process-oriented conceptions of law, it crosses legal and political science traditions to explore the ways in which EU counter-terrorism law and policy acquire and maintain social appropriateness....... versus justice equation, on the issues of privacy and data protection, and on the broader respect for fundamental rights more generally. In this process, the legitimacy and the social appropriateness of some of these measures have been questioned, both at the societal level and before or by European...

  1. Performance of Scintillator Counters with Silicon Photomultiplier Readout

    CERN Document Server

    Artikov, A; Chokheli, D; Davydov, Yu I; Dukes, E C; Ehrlich, R; Francis, K; Frank, M J; Glagolev, V; Hansen, S; Hocker, A; Oksuzian, Y; Rubinov, P; Song, E; Uzunyan, S; Wu, Y

    2015-01-01

    The performance of scintillator counters with embedded wavelength-shifting fibers has been measured in the Fermilab Meson Test Beam Facility using 120 GeV protons. The counters were extruded with a titanium dioxide surface coating and two channels for fibers at the Fermilab NICADD facility. Each fiber end is read out by a 2*2 mm^2 silicon photomultiplier. The signals were amplified and digitized by a custom-made front-end electronics board. Combinations of 5*2 cm^2 and 6*2 cm^2 extrusion profiles with 1.4 and 1.8 mm diameter fibers were tested. The design is intended for the cosmic-ray veto detector for the Mu2e experiment at Fermilab. The light yield as a function of the transverse and longitudinal position of the beam will be given.

  2. Organizational Identity Negotiations through Dominant and Counter Narratives

    DEFF Research Database (Denmark)

    Humle, Didde; Frandsen, Sanne

    In this paper, we see the organization as a polyphonic, storytelling community and study the role of dominant and counter narratives in organizational identity formation processes as a web of stories performed and negotiated by organizational members and external stakeholders. Based on a case stu......, while simultaneously establishing and maintaining a sense of continuity and stability around their organization and work despite identity threats, ambiguities and contradictions inherent in their role.......In this paper, we see the organization as a polyphonic, storytelling community and study the role of dominant and counter narratives in organizational identity formation processes as a web of stories performed and negotiated by organizational members and external stakeholders. Based on a case study...

  3. Fully Countering Trusting Trust through Diverse Double-Compiling

    CERN Document Server

    Wheeler, David A

    2010-01-01

    An Air Force evaluation of Multics, and Ken Thompson's Turing award lecture ("Reflections on Trusting Trust"), showed that compilers can be subverted to insert malicious Trojan horses into critical software, including themselves. If this "trusting trust" attack goes undetected, even complete analysis of a system's source code will not find the malicious code that is running. Previously-known countermeasures have been grossly inadequate. If this attack cannot be countered, attackers can quietly subvert entire classes of computer systems, gaining complete control over financial, infrastructure, military, and/or business systems worldwide. This dissertation's thesis is that the trusting trust attack can be detected and effectively countered using the "Diverse Double-Compiling" (DDC) technique, as demonstrated by (1) a formal proof that DDC can determine if source code and generated executable code correspond, (2) a demonstration of DDC with four compilers (a small C compiler, a small Lisp compiler, a small malic...

  4. Doing Forensic on DTUsat-2 Using the Beacon Counter

    DEFF Research Database (Denmark)

    Fléron, René

    2016-01-01

    DTUsat-2 was launched into a Polar LEO on a Dnepr rocket out of Yasny on 19th June 2014. After the first few days of beacon recording and precise orbit determination it became apparent that all was not nominal. One notable thing was the relatively low beacon count number. The beacon count reflects...... how many times the communication system has generated and transmitted a beacon. When nominal the number will reach 32767 in about 22.5 days before rolling over. Not only did we observe a low beacon count number but most surprisingly the counter seemed the restart right before AOS when the satellite...... AOS were the satellite should have maximum power. A thorough investigation using modelling and beacon count mapping has been conducted in order to understand why the satellite does not operate nominally and why the beacon counter maps out contradictive to our initial understandings....

  5. Financial Worldwide Crisis: The Anti-Counter Cycle of Australia

    Directory of Open Access Journals (Sweden)

    Joao NEGREIROS

    2013-12-01

    Full Text Available If Australia has been subject to major influences by the United States and European countries, why is its economy healthier than their counter partners? What are the economic foundations that underline this anti-counter cycle of financial worldwide crisis from Australia? What are some of the lessons that countries from Europe that have not fared during the current financial worldwide crisis should learn from Australia? The purpose of this paper is to review the present Australian management system. Four changes are identified including embracement of corporate governance, a shift to adopt more R&D activities, a shift to adopt environmental sustainability practices and emerging corporate social responsibility. On the conclusions settings, a recap and recommendation on how Portugal, a member of the PIGS (Portugal, Italy, Greece and Spain Southern European Countries club forgot to embrace directives that have been applied in Australia, to avoid the actual financial and identity crisis.

  6. Hegemony and Counter-Hegemony in a Global Field

    Directory of Open Access Journals (Sweden)

    William Carroll

    2007-03-01

    Full Text Available Social justice struggles are often framed around competing hegemonic and counter-hegemonic projects. This article compares several organizations of global civil society that have helped shape or have emerged within the changing political-economic landscape of neoliberal globalization, either as purveyors of ruling perspectives or as anti-systemic popular forums and activist groups. It interprets the dialectical relation between the two sides as a complex war of position to win new political space by assembling transnational historic blocs around divergent social visions – the one centered on a logic of replication and passive revolution, the other centred on a logic of prefiguration and transformation. It presents a sociological analysis of the organizational forms and practical challenges that their respective hegemonic and counter-hegemonic projects entail.

  7. Effect of counter current gas phase on liquid film

    Institute of Scientific and Technical Information of China (English)

    Shujuan LUO; Huaizhi LI; Weiyang FEI; Yundong WANG

    2009-01-01

    Liquid film flow is very important in many industrial applications. However, there are few reports about its characteristics on structured packings. Therefore, in this paper, liquid film phenomena were investigated experimentally to exploit new approaches for intensifying the performance of the structured packings. All experiments were performed at room temperature. Water and air were the working fluids. The effect of counter current gas phase on the liquid film was taken into consideration. A high speed camera, a non-intrusive measurement technique, was used. It is shown that both liquid and gas phases have strong effects on film characteristics. In the present work, liquid film width increased by 57% because of increasing liquid flow rate, while it decreased by 25% resulting from the counter current gas phase.

  8. PLASMA EMISSION BY COUNTER-STREAMING ELECTRON BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Ziebell, L. F.; Petruzzellis, L. T.; Gaelzer, R. [Instituto de Física, UFRGS, Porto Alegre, RS (Brazil); Yoon, P. H. [Institute for Physical Science and Technology, University of Maryland, College Park, MD (United States); Pavan, J., E-mail: luiz.ziebell@ufrgs.br, E-mail: yoonp@umd.edu, E-mail: joel.pavan@ufpel.edu.br [Instituto de Física e Matemática, UFPel, Pelotas, RS (Brazil)

    2016-02-10

    The radiation emission mechanism responsible for both type-II and type-III solar radio bursts is commonly accepted as plasma emission. Recently Ganse et al. suggested that type-II radio bursts may be enhanced when the electron foreshock geometry of a coronal mass ejection contains a double hump structure. They reasoned that the counter-streaming electron beams that exist between the double shocks may enhance the nonlinear coalescence interaction, thereby giving rise to more efficient generation of radiation. Ganse et al. employed a particle-in-cell simulation to study such a scenario. The present paper revisits the same problem with EM weak turbulence theory, and show that the fundamental (F) emission is not greatly affected by the presence of counter-streaming beams, but the harmonic (H) emission becomes somewhat more effective when the two beams are present. The present finding is thus complementary to the work by Ganse et al.

  9. Proposition of Unique Pumping System with Counter-Rotating Mechanism

    Directory of Open Access Journals (Sweden)

    Toshiaki Kanemoto

    2004-01-01

    Full Text Available Turbo-pumps have weak points, such as when the pumping operation becomes unstable in the rising portion of the head characteristics and/or the cavitation occurs under the intolerably low suction head. To overcome both weak points simultaneously, this article proposes a unique pumping system with counter-rotating mechanism, which consists of two stage impellers and a peculiar motor with double rotors. The front and the rear impellers are driven by the inner and the outer rotors of the motor, respectively, keeping the relative rotational speed constant and counter-balancing the rotational torque. Such driving conditions not only smartly improve the unstable performance at lower discharge, but also suppress the cavitation at higher discharge, in the optimum cooperation with the impeller works and the rotor outputs.

  10. Flooding in counter-current two-phase flow

    Energy Technology Data Exchange (ETDEWEB)

    Ragland, W.A.; Ganic, E.N.

    1982-01-01

    Flooding is a phenomenon which is best described as the transition from counter-current to co-current flow. Early notice was taken of this phenomenon in the chemical engineering industry. Flooding also plays an important role in the field of two-phase heat transfer since it is a limit for many systems involving counter-current flow. Practical applications of flooding limited processes include wickless thermosyphons and the emergency core cooling system (ECCS) of pressurized water nuclear reactors. The phenomenon of flooding also is involved in the behavior of nuclear reactor core materials during severe accident conditions where flooding is one of the mechanisms governing the motion of the molten fuel pin cladding.

  11. Pakistan’s Security Paradox: Countering and Fomenting Insurgencies

    Science.gov (United States)

    2009-12-01

    Brookings Institu- tion’s Foreign Policy Studies (U.S.-Pakistan Relations), Woodrow Wilson International Center for Scholars (Pakistan’s Political Economy ...discussion of how Pakistan drafted and implemented policies to counter and create insurgencies between 1948 and 2001. Pakistan’s Uber -National Security...Strategy Pakistan’s Uber -National Security Strategy is a function of the conditions surrounding the creation of the nation state, its multiethnic

  12. The Efficacy of Foreign Assistance in Counter Narcotics

    Science.gov (United States)

    2013-03-01

    by ADAM, 30,910 hectares were converted from coca to coffee57. Figure 3. Coffee Prices Versus the Amount of Cultivated Coca Oil palm has also... cultivation has grown to 452435 hectares.58 Requiring approximately one worker per eight hectares, the palm oil industry employs...for cocaine. In a 2006 study, Stella M. Rouse and Moises Arce analyzed the effects of U.S. counter narcotic policy on coca cultivation in Peru

  13. Cloud condensation nucleus counter by impactor sampling technique

    Science.gov (United States)

    Ohtake, T.

    1981-01-01

    Unlike typical CCN counters, this device counts the numbers of water droplets condensed on aerosol particles sampled on a microcover glass at various different relative humidities. The relative humidities ranged from 75 percent to a calculated value of 110 percent. A schematic of the apparatus is shown. The individual CCN can be identified in an optical micrograph and scanning electron micrograph and may be inspected for their chemical composition later.

  14. Atomic Interferometry with Detuned Counter-Propagating Electromagnetic Pulses

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Ming -Yee [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-09-05

    Atomic fountain interferometry uses atoms cooled with optical molasses to 1 μK, which are then launched in a fountain mode. The interferometer relies on the nonlinear Raman interaction of counter-propagating visible light pulses. We present models of these key transitions through a series of Hamiltonians. Our models, which have been verified against special cases with known solutions, allow us to incorporate the effects of non-ideal pulse shapes and realistic laser frequency or wavevector jitter.

  15. Large scale test of wedge shaped micro strip gas counters

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, M.; Atz, S.; Aulchenko, V.; Bachmann, S.; Baiboussinov, B.; Barthe, S.; Beaumont, W.; Beckers, T.; Beissel, F.; Benhammou, Y.; Bergdolt, A.M.; Bernier, K.; Bluem, P.; Bondar, A.; Bouhali, O.; Boulogne, I.; Bozzo, M.; Brom, J.M.; Camps, C.; Chorowicz, V.; Coffin, J.; Commichau, V.; Contardo, D.; Croix, J.; Troy, J. de; Drouhin, F.; Eberle, H.; Fluegge, G.; Fontaine, J.-C.; Geist, W.; Goerlach, U.; Gundlfinger, K.; Hangarter, K.; Haroutunian, R.; Helleboid, J.M.; Henkes, Th.; Hoffer, M.; Hoffman, C.; Huss, D.; Ischebeck, R.; Jeanneau, F.; Juillot, P.; Junghans, S.; Kapp, M.R.; Kaercher, K.; Knoblauch, D.; Kraeber, M.; Krauth, M.; Kremp, J.; Lounis, A.; Luebelsmeyer, K.; Maazouzi, C.; Macke, D.; Metri, R.; Mirabito, L.; Mueller, Th.; Nagaslaev, V.; Neuberger, D.; Nowack, A.; Pallares, A.; Pandoulas, D.; Petertill, M.; Pooth, O.; Racca, C.; Ripp, I.; Ruoff, E.; Sauer, A.; Schmitz, P.; Schulte, R.; Schultz von Dratzig, A.; Schunk, J.P.; Schuster, G.; Schwaller, B.; Shektman, L.; Siedling, R.; Sigward, M.H.; Simonis, H.J.; Smadja, G.; Stefanescu, J.; Szczesny, H.; Tatarinov, A.; Thuemmel, W.H.; Tissot, S.; Titov, V.; Todorov, T.; Tonutti, M.; Udo, F.; Velde, C. Vander. E-mail: vandervelde@hep.iihe.ac.be; Doninck, W. van; Dyck, Ch. van; Vanlaer, P.; Lancker, L. van; Verdini, P.G.; Weseler, S.; Wittmer, B.; Wortmann, R.; Zghiche, A.; Zhukov, V

    1999-11-01

    In order to check the system aspects of the forward-backward MSGC tracker designed for the future CMS experiment at LHC, 38 trapezoidal MSGC counters assembled in six multi-substrates detector modules were built and exposed to a muon beam at the CERN SPS. Results on the gain uniformity along the wedge-shaped strip pattern and across the detector modules are shown together with measurements of the detection efficiency and the spatial resolution.

  16. Large scale test of wedge shaped micro strip gas counters

    CERN Document Server

    Ackermann, M; Aulchenko, V M; Bachmann, S; Baibusinov, B O; Barthe, S; Beaumont, W; Beckers, T; Beissel, F; Benhammou, Ya; Bergdolt, A M; Bernier, K; Blüm, H P; Bondar, A E; Bouhali, O; Boulogne, I; Bozzo, M; Brom, J M; Camps, C; Chorowicz, V; Coffin, J P; Commichau, V; Contardo, D; Croix, J; De Troy, J G; Drouhin, F; Eberle, H; Flügge, G; Fontaine, J C; Geist, Walter M; Goerlach, U; Gundlfinger, K; Hangarter, K; Haroutunian, R; Helleboid, J M; Henkes, T; Hoffer, M; Hoffmann, C; Huss, D; Ischebeck, R; Jeanneau, F; Juillot, P; Junghans, S; Kapp, M R; Kärcher, K; Knoblauch, D; Kräber, M H; Krauth, M; Kremp, J; Lounis, A; Lübelsmeyer, K; Maazouzi, C; Macke, D; Metri, R; Mirabito, L; Müller, T; Nagaslaev, V; Neuberger, D; Nowak, A; Pallarès, A; Pandoulas, D; Petertill, M; Pooth, O; Racca, C; Ripp, I; Ruoff, E; Sauer, A; Schmitz, P; Schulte, R; Schultz von Dratzig, A; Schunk, J P; Schuster, G; Schwaller, B; Shekhtman, L I; Siedling, R; Sigward, M H; Simonis, H J; Smadja, G; Stefanescu, J; Szczesny, H; Tatarinov, A A; Thümmel, W H; Tissot, S; Titov, V; Todorov, T; Tonutti, M; Udo, Fred; Van der Velde, C; Van Doninck, W K; Van Dyck, C; Vanlaer, P; Van Lancker, L; Verdini, P G; Weseler, S; Wittmer, B; Wortmann, R; Zghiche, A; Zhukov, V

    1999-01-01

    In order to check the system aspects of the forward-backward MSGC tracker designed for the future CMS experiment at LHC, 38 trapezoidal MSGC counters assembled in six multi-substrates detector modules were built and exposed to a muon beam at the CERN SPS. Results on the gain uniformity along the wedge-shaped strip pattern and across the detector modules are shown together with measurements of the detection efficiency and the spatial resolution. (8 refs).

  17. Psychogeographical counter-tour guiding: Theory\\ud and practice

    OpenAIRE

    2015-01-01

    In this paper, will be outlined and explained a mode of tour guiding referred to as ‘psychogeographical’ counter-tour guiding that has been conducted in Manchester, Huddersfield and Leeds with groups such as the Huddersfield Psychogeography Network, the Loiterers Resistance Movement and the Leeds Psychogeography Group. The usage of psychogeography here draws on elements of the situationist practice of playful wandering without destination in order to: experientially make sense of and creative...

  18. Cloud characterization using a particle-counter dropsonde

    Science.gov (United States)

    Ulanowski, Zbigniew; Kaye, Paul Henry; Hirst, Edwin; Wieser, Andreas; Stanley, Warren

    2015-04-01

    Routine meteorological data is obtained in the atmosphere using disposable radiosondes, giving temperature, pressure, humidity and wind speed. Additional measurements are obtained from dropsondes, released from research aircraft. However, a crucial property not yet measured is the size and concentration of atmospheric particulates, including cloud particles or aerosols. Instead, indirect measurements are employed, relying on remote sensing. In addition, research aircraft can be used in situ, but airborne measurements are expensive, and aircraft use is restricted to near-horizontal profiling, which can be a limitation, as phenomena such convection develop in the vertical direction. The Centre for Atmospheric and Instrumentation Research at University of Hertfordshire develops light-scattering instruments for the characterization of aerosols and cloud particles. Recently a range of low-cost, miniature particle counters has been created, intended for use with systems such as disposable balloon-borne radiosondes, dropsondes, or in dense ground-based sensor networks. Versions for different particle size ranges exist. They have been used for vertical profiling of aerosols such as mineral dust or volcanic ash. However, a disadvantage of optical particle counters that sample through a narrow inlet is that they can become blocked, which can happen in a cloud, for example. Hence, a different counter version has been developed, which can have open-path geometry, as the sensing zone is defined optically rather than being delimited by the flow system. This counter is currently being used by the UK Met Office in a ground-based fog monitoring network. It has also been adapted for use with radiosondes or dropsondes. The dropsonde version has been successfully tested by launching it from research aircraft together with the so-called KITsonde, developed at the Karlsruhe Institute of Technology, which determines standard meteorological variables and GPS position for transmission back

  19. Use of CLYC spectrometer in counter-terrorism applications

    Science.gov (United States)

    Ing, H.; Smith, M. B.; Koslowsky, M. R.; Andrews, H. R.

    2015-05-01

    A new scintillator crystal, now known as CLYC (Cs2LiYCl6:Ce), has been under development for over 15 years (1). It was primarily of interest for radiation detection applications because of its good energy resolution for gamma rays (counter-terrorism scenarios where neutrons may be involved. The relative importance of the fast neutron response of CLYC, compared to the thermal and gamma-ray response, will be discussed for these scenarios.

  20. The time response function of spark counters and RPCs

    Energy Technology Data Exchange (ETDEWEB)

    Gobbi, A. E-mail: a.gobbi@gsi.de; Mangiarotti, A. E-mail: mangiaro@fi.infn.it

    2003-08-01

    The fluctuation theory for the avalanche growth with and without space charge effects is briefly summarized and compared to a broad field of applications. These include spark counters as well as timing and trigger RPCs operated in avalanche mode. A large domain in electrical field strength, pressure, gap size and gas mixture type is covered. A reasonable agreement with the experiment is observed, giving confidence on the validity of both assumptions and treatment of the theory.

  1. Low Sheet Resistance Counter Electrode in Dye-sensitized Solar Cell

    Institute of Scientific and Technical Information of China (English)

    Gui Qiang WANG; Rui Feng LIN; Miao WANG; Chang Neng ZHANG; Yuan LIN; Xu Rui XIAO; Xue Ping LI

    2004-01-01

    In order to search for the high efficiency and low sheet resistance counter electrode in dye-sensitized solar cell, we used Ti plate as the conducting substrate to prepare the counter electrode by thermal decomposition of H2PtCl6. Ti plate counter electrode shows low sheet resistance, good reflecting performance and matching kinetics. The dye-sensitized solar cell with the Ti plate counter electrode shows better photovoltaic performance than that of the cell with the fluorine-doped tin oxide-coated glass counter electrode.

  2. Orthogonal wavelet analysis of counter gradient transport phenomena in turbulent asymmetric channel flow

    Institute of Scientific and Technical Information of China (English)

    Jianbo Jiang; Xiang Qiu; Zhiming Lu; Yulu Liu

    2005-01-01

    In this paper four families of orthogonal wavelets are applied to analyze the turbulent counter gradient transport phenomena in fully developed asymmetric channel flows,The results show that: (1) In the instance of counter gradient transport, the principal scale of the coherent structure is responsible for the strong local counter gradient transport; (2)Counter gradient transport phenomena have a strong effect on the intermittency of turbulence; (3) Non-Gaussian part of the principal coherent structure is essential for counter gradient transport phenomena.

  3. Unstable $m=1$ modes of counter-rotating Keplerian discs

    CERN Document Server

    Gulati, Mamta; Sridhar, S

    2012-01-01

    We study the linear $m=1$ counter-rotating instability in a two-component, nearly Keplerian disc. Our goal is to understand these \\emph{slow} modes in discs orbiting massive black holes in galactic nuclei. They are of interest not only because they are of large spatial scale--and can hence dominate observations--but also because they can be growing modes that are readily excited by accretion events. Self-gravity being nonlocal, the eigenvalue problem results in a pair of coupled integral equations, which we derive for a two-component softened gravity disc. We solve this integral eigenvalue problem numerically for various values of mass fraction in the counter-rotating component. The eigenvalues are in general complex, being real only in the absence of the counter-rotating component, or imaginary when both components have identical surface density profiles. Our main results are as follows: (i) the pattern speed appears to be non negative, with the growth (or damping) rate being larger for larger values of the ...

  4. A Hardware Architecture of a Counter-Based Entropy Coder

    Directory of Open Access Journals (Sweden)

    Armein Z R Langi

    2012-04-01

    Full Text Available This paper describes a hardware architectural design of a real-time counter based entropy coder at a register transfer level (RTL computing model. The architecture is based on a lossless compression algorithm called Rice coding, which is optimal for an entropy range of bits per sample. The architecture incorporates a word-splitting scheme to extend the entropy coverage into a range of bits per sample. We have designed a data structure in a form of independent code blocks, allowing more robust compressed bitstream. The design focuses on an RTL computing model and architecture, utilizing 8-bit buffers, adders, registers, loader-shifters, select-logics, down-counters, up-counters, and multiplexers. We have validated the architecture (both the encoder and the decoder in a coprocessor for 8 bits/sample data on an FPGA Xilinx XC4005, utilizing 61% of F&G-CLBs, 34% H-CLBs, 32% FF-CLBs, and 68% IO resources. On this FPGA implementation, the encoder and decoder can achieve 1.74 Mbits/s and 2.91 Mbits/s throughputs, respectively. The architecture allows pipelining, resulting in potentially maximum encoding throughput of 200 Mbit/s on typical real-time TTL implementations. In addition, it uses a minimum number of register elements. As a result, this architecture can result in low cost, low energy consumption and reduced silicon area realizations.

  5. Digital Electronics for the Pierre Auger Observatory AMIGA Muon Counters

    CERN Document Server

    Wainberg, O; Platino, M; Sanchez, F; Suarez, F; Lucero, A; Videla, M; Wundheiler, B; Melo, D; Hampel, M; Etchegoyen, A

    2013-01-01

    The "Auger Muons and Infill for the Ground Array" (AMIGA) project provides direct muon counting capacity to the Pierre Auger Observatory and extends its energy detection range down to 0.3 EeV. It currently consists of 61 detector pairs (a Cherenkov surface detector and a buried muon counter) distributed over a 23.5 km2 area on a 750 m triangular grid. Each counter relies on segmented scintillator modules storing a logical train of '0's and '1's on each scintillator segment at a given time slot. Muon counter data is sampled and stored at 320 MHz allowing both the detection of single photoelectrons and the implementation of an offline trigger designed to mitigate multi-pixel PMT crosstalk and dark rate undesired effects. Acquisition is carried out by the digital electronics built around a low power Cyclone III FPGA. This paper presents the digital electronics design, internal and external synchronization schemes, hardware tests, and first results from the Observatory.

  6. Counter Rotating Fans—An Aircraft Propulsion for the Future?

    Institute of Scientific and Technical Information of China (English)

    Peter Schimming

    2003-01-01

    In the mid seventies a new propulsor for aircraft was designed and investigated-the so-called PROPFAN.With regard to the total pressure increase, it ranges between a conventional propeller and a turbofan with very high bypass ratio.This new propulsion system promised a reduction in fuel consumption of 15 to 25% compared to engines at that time. A lot of propfans (Hamilton Standard, USA) with different numbers of blades and blade shapes have been designed and tested in wind tunnels in order to find an optimum in efficiency, Fig. 1. Parallel to this development GE, USA, made a design of a counter rotating unducted propfan, the so-called UDF, Fig.2. A prototype engine was manufactured and investigated on an in-flight test bed mounted at the MD82 and the B727. Since that time there has not been any further development of propfans (except AN 70 with NK 90—engine, Ukraine, which is more or less a propeller design) due to relatively low fuel prices and technical obstacles. Only technical programs in different countries are still going on in order to prepare a data base for designing counter rotating fans in terms of aeroacoustics, aerodynamics and aeroelasticities.In DLR, Germany, a lot of experimental and numerical work has been undertaken to understand the physical behaviour of the unsteady flow in a counter rotating fan.

  7. Countering violent extremism via de-securitisation on Twitter

    Directory of Open Access Journals (Sweden)

    Anna Warrington

    2017-06-01

    Full Text Available The case of a civil society actor on Twitter entering a securitized discourse on terrorism illustrates the transformative theoretical potential that emerges from new forms of communication online. Through a qualitative analysis of tweets from the Average Mohamed profile, the potential to change a negative narrative of violent extremism operating within a securitised discourse of Islamic terrorism, is discussed in an online context. The arguments forming from this analysis offers a new approach to studying online counter narratives by linking a theoretical framework of securitisation and de-securitisation to recent political efforts Countering Violent Extremism (CVE and Preventing Violent Extremism (PVE. Through the inclusion of a civil society Twitter account as an illustrative case, this paper explores how social media can challenge existing assumptions of who can be a de-securitising actor within security theory by blurring the lines between political and societal sectors in a securitised threat from Islamic terrorism. If and how a civil society actor can loosen the dichotomous discursive relationship between Self/Other relations within a contemporary discourse on terrorism becomes relevant for a theoretical discussion by presenting an argument suggesting that online CVE polices are more effective within the sphere of ‘normal’ politics rather than within the realm of securitization. This theoretical perspective offers an analytical framework including a wide range of actors involved in counter narratives policies which is useful for further CVE research.

  8. HATE BENEATH THE COUNTER SPEECH? A QUALITATIVE CONTENT ANALYSIS OF USER COMMENTS ON YOUTUBE RELATED TO COUNTER SPEECH VIDEOS

    Directory of Open Access Journals (Sweden)

    Julian Ernst

    2017-03-01

    Full Text Available The odds in stumbling over extremist material in the internet are high. Counter speech videos, such as those of the German campaign Begriffswelten Islam (Concepts of Islam; Bundeszentrale für politische Bildung, 2015a published on YouTube, offer alternative perspectives and democratic ideas to counteract extremist content. YouTube users may discuss these videos in the comment sections below the video. Yet, it remains open which topics these users bring up in their comments. Moreover, it is unknown how far user comments in this context may promote hate speech—the very opposite of what counter speeches intent to evoke. By applying a qualitative content analysis on a randomly selected sample of user comments, which appeared beneath the counter speech videos of Concepts of Islam, we found that comments dominated, which dealt with devaluating prejudices and stereotypes towards Muslims and/or Islam. However, we also discovered that users in a large scale discussed the content of the videos. Moreover, we identified user comments, which hint at hateful speech either in comments themselves or the discourse the comments are embedded in. Based on these results, we discuss implications for researchers, practitioners and security agencies.

  9. LOAC (Light Optical Particle Counter): a new small aerosol counter with particle characterization capabilities for surface and airborne measurements

    Science.gov (United States)

    Renard, Jean-Baptiste; Berthet, Gwenael; Jégou, Fabrice; Jeannot, Matthieu; Jourdain, Line; Dulac, François; Mallet, Marc; Dupont, Jean-Charles; Thaury, Claire; Tonnelier, Thierry; Verdier, Nicolas; Charpentier, Patrick

    2013-04-01

    The determination of the size distribution of tropospheric and stratospheric aerosols with conventional optical counters is difficult when different natures of particles are present (droplets, soot, mineral dust, secondary organic or mineral particles...). Also, a light and cheap aerosol counter that can be used at ground, onboard drones or launched under all kinds of atmospheric balloons can be very useful during specific events as volcanic plumes, desert dust transport or local pollution episodes. These goals can be achieved thanks to a new generation of aerosol counter, called LOAC (Light Optical Aerosol Counter). The instrument was developed in the frame of a cooperation between French scientific laboratories (CNRS), the Environnement-SA and MeteoModem companies and the French Space Agency (CNES). LOAC is a small optical particle counter/sizer of ~250 grams, having a low electrical power consumption. The measurements are conducted at two scattering angles. The first one, at 12°, is used to determine the aerosol particle concentrations in 19 size classes within a diameter range of 0.3-100 micrometerers. At such an angle close to forward scattering, the signal is much more intense and the measurements are the least sensitive to the particle nature. The second angle is at 60°, where the scattered light is strongly dependent on the particle refractive index and thus on the nature of the aerosols. The ratio of the measurements at the two angles is used to discriminate between the different types of particles dominating the nature of the aerosol particles in the different size classes. The sensor particularly discriminates wet or liquid particles, soil dust and soot. Since 2011, we have operated LOAC in various environments (Arctic, Mediterranean, urban and peri-urban…) under different kinds of balloons including zero pressure stratospheric, tethered, drifting tropospheric, and meteorological sounding balloons. For the last case, the total weight of the gondola

  10. Swot analysis of using aerostats for surveillance in counter terrorism

    Science.gov (United States)

    ćetin, Hüseyin

    2013-06-01

    In today's conjuncture, the terrorist activities are the most compelling issue for the defence forces in maintaining homeland security. Especially, the terrorist elements that penetrate the homeland may give harm. This harm can be minimized by preventing the terrorist penetrations from homeland borders. In counter terrorism, having Intelligence, Surveillance and Reconnaissance (ISR) capability and using this capability by twenty four hours is deterrence for the terrorist groups. Aerostats emerge as the ideal platform which can provide this capability. Aerostats are unmanned and aerodynamically shaped balloons that are stayed in the air, fixed to the ground by steel cable(s). The aerostat is made of a large fabric envelope that is filled with nonflammable helium gas, which provides the lifting force. The cables also serve to supply the electrical power to the aerostat systems, and for data relay between the aerostat and the ground station. Aerostats are different from the other manned and Unmanned Aerial Vehicles (UAVs) because of aerostats' capabilities such as cost effectiveness, long endurance and high resolution image transmission. Especially having uninterrupted image transmission and surveillance capabilities is important to be advantageous in counter terrorism. In this article, a short definition of terrorism has been given and then the importance of ensuring the homeland border security has been emphasized in counter terrorism. In addition, the questions of "what are the technical capabilities, the usage areas and the purposes of aerostats?" will be introduced as a result of literature review. Finally the strengths and weaknesses of aerostats, opportunities and threats for the near future will be introduced by using "SWOT" analysis method.

  11. GAYA PSYCHEDELIA COUNTER CULTURE AMERIKA KOMODIFIKASI INDONESIA KINI

    Directory of Open Access Journals (Sweden)

    Baskoro Suryo Banindro

    2007-01-01

    Full Text Available The art of psychedelia is an example of art that uses a nation’s cultural consciousness as a source of expression of the past. Conceptually, the spirit of this art is to connect the modern movement with the effects of drug use. The American youths utilized this movement as counter culture that gave the birth to the flower generation in a settled community. Psychedelic style which in the beginning was an identity, a symbol of anti settledness, and Uncle Sam’s youth’s fight against its politics in the 1960’s. At the end it became the signs of times. The zeitgeist movement in the next decade entered Indonesia with new packaging that transforms into comodification that can be applied to various media through popular culture of its youths. Abstract in Bahasa Indonesia: Seni penggunaan kesadaran budaya bangsa untuk diubah sebagai sumber pengungkapan yang terjadi di masa lalu salah satu contohnya ialah “seni psychedelic”. Secara konseptual jiwa seni ini ialah menghubungkan kepada pergerakan modern yang berhubungan dengan perasaan yang diakibatkan oleh pengaruh obat bius. Kaum muda Amerika meman¬faat¬kan pergerakan ini sebagai budaya tanding “counter culture” yang melahirkan “generasi bunga” di komunitas yang telah mapan. Gaya psychedelia yang pada mulanya dijadikan “jati diri” dan simbol anti kemapanan dan perlawanan kawula muda negara “Paman Sam” terhadap kebijakan politik di negaranya tahun 1960an, pada akhirnya menjadi sebuah penanda jaman. Gelombang “zeitgeist” ini pada dekade berikutnya masuk ke Nusantara dengan “kemasan baru” yang menjelma dalam bentuk komodifikasi yang aplikatif di berbagai media melalui budaya popular yang lekat di hati generasi muda Indonesia. Kata kunci: gaya, psychedelic, counter culture, komodifikasi.

  12. Hierarchical steepness, counter-aggression, and macaque social style scale.

    Science.gov (United States)

    Balasubramaniam, Krishna N; Dittmar, Katharina; Berman, Carol M; Butovskaya, Marina; Cooper, Mathew A; Majolo, Bonaventura; Ogawa, Hideshi; Schino, Gabriele; Thierry, Bernard; De Waal, Frans B M

    2012-10-01

    Nonhuman primates show remarkable variation in several aspects of social structure. One way to characterize this variation in the genus Macaca is through the concept of social style, which is based on the observation that several social traits appear to covary with one another in a linear or at least continuous manner. In practice, macaques are more simply characterized as fitting a four-grade scale in which species range from extremely despotic (grade 1) to extremely tolerant (grade 4). Here, we examine the fit of three core measures of social style-two measures of dominance gradients (hierarchical steepness) and another closely related measure (counter-aggression)-to this scale, controlling for phylogenetic relationships. Although raw scores for both steepness and counter-aggression correlated with social scale in predicted directions, the distributions appeared to vary by measure. Counter-aggression appeared to vary dichotomously with scale, with grade 4 species being distinct from all other grades. Steepness measures appeared more continuous. Species in grades 1 and 4 were distinct from one another on all measures, but those in the intermediate grades varied inconsistently. This confirms previous indications that covariation is more readily observable when comparing species at the extreme ends of the scale than those in intermediate positions. When behavioral measures were mapped onto phylogenetic trees, independent contrasts showed no significant consistent directional changes at nodes below which there were evolutionary changes in scale. Further, contrasts were no greater at these nodes than at neutral nodes. This suggests that correlations with the scale can be attributed largely to species' phylogenetic relationships. This could be due in turn to a structural linkage of social traits based on adaptation to similar ecological conditions in the distant past, or simply to unlinked phylogenetic closeness.

  13. High-Precision Spectroscopy with Counter-Propagating Femtosecond Pulses

    CERN Document Server

    Barmes, Itan; Eikema, Kjeld S E

    2013-01-01

    An experimental realization of high-precision direct frequency comb spectroscopy using counter-propagating femtosecond pulses on two-photon atomic transitions is presented. Doppler broadened background signal, hampering precision spectroscopy with ultrashort pulses, is effectively eliminated with a simple pulse shaping method. As a result, all four 5S-7S two-photon transitions in a rubidium vapor are determined with both statistical and systematic uncertainties below 10$^{-11}$, which is an order of magnitude better than previous experiments on these transitions.

  14. Efficient counter-propagating wave acoustic micro-particle manipulation

    Science.gov (United States)

    Grinenko, A.; Ong, C. K.; Courtney, C. R. P.; Wilcox, P. D.; Drinkwater, B. W.

    2012-12-01

    A simple acoustic system consisting of a pair of parallel singe layered piezoelectric transducers submerged in a fluid used to form standing waves by a superposition of two counter-propagating waves is reported. The nodal positions of the standing wave are controlled by applying a variable phase difference to the transducers. This system was used to manipulate polystyrene micro-beads trapped at the nodal positions of the standing wave. The demonstrated good manipulation capability of the system is based on a lowering of the reflection coefficient in a narrow frequency band near the through-thickness resonance of the transducer plates.

  15. Deadtime calibration in high-rate microstrip gas counters

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: dom.duxbury@stfc.ac.u [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)

    2010-09-21

    The advent of the microstrip gas chamber (MSGC) has permitted the development of position-sensitive gas avalanche detectors, which combine sub-millimeter spatial resolution with multi-MHz global rate capabilities not attainable with traditional types of gas counters. Based on massively parallel electronic readout, the need to keep down electronic channel costs imposes a simple front-end design without in-built deadtime compensation. In this report we show that insitu calibration of the deadtime of the detector system is straight-forward and reliable. Methods are described for applications to X-ray and neutron detection.

  16. Counter-current chromatography of black tea infusions.

    Science.gov (United States)

    Wedzicha, B L; Lo, M F; Donovan, T J

    1990-05-04

    Counter-current chromatography using a multilayer coil planet centrifuge, with solvent system ethyl acetate-butanol-water, permits the separation of black tea infusions into fractions which include pure SII and a mixture of SI and SIa thearubigins. Good resolution of several components of the infusion may be achieved in elution times of 1 to 2 h. The appearance of chromatograms is altered on decaffeinating the infusion. The effect of stationary phase composition is considered. Resolution of the peaks improves with butanol content.

  17. High-level neutron coincidence counter maintenance manual

    Energy Technology Data Exchange (ETDEWEB)

    Swansen, J.; Collinsworth, P.

    1983-05-01

    High-level neutron coincidence counter operational (field) calibration and usage is well known. This manual makes explicit basic (shop) check-out, calibration, and testing of new units and is a guide for repair of failed in-service units. Operational criteria for the major electronic functions are detailed, as are adjustments and calibration procedures, and recurrent mechanical/electromechanical problems are addressed. Some system tests are included for quality assurance. Data on nonstandard large-scale integrated (circuit) components and a schematic set are also included.

  18. Implementasi Counter Production Monitoring pada Mesin Tekstil berbasis Mikrokontroler

    Directory of Open Access Journals (Sweden)

    HENDI HANDIAN RACHMAT

    2016-02-01

    Full Text Available Abstrak Sistem Counter Production Monitoring (CPM diimplementasikan untuk menghitung secara otomotis kecepatan mesin, kecepatan produksi, dan jumlah produksi.Sistem ini digunakan pada mesin pemintal benang di industri tekstil untuk mengetahui efisiensi kerja mesin dan hasil produksi benang.Sistem terdiri dari perangkat keras dan lunak berbasis mikrokontroler dan personal komputer (PC untuk mengukur putaran mesin guna menghitung ketiga besaran hasil produksi. Inductive proximity sensor dan encoder gear dipasang dengan jarak 1 mm pada shaft mesin yang berputar untuk mendeteksi jumlah putaran mesin berdasarkan jumlah pulsa yang dideteksi oleh sensor selama durasi tertentu. Mikrokontroller menghitung tiga besaran produksi dan menampilkan hasil pada display LCD melalui pengaturan 3 buah tombol serta mengirimkan ke PC melalui komunikasi serial untuk ditampilkan. Hasil pengujian selama 3 hari menunjukkan terjadi perbedaan antara sistem CPM dan perhitungan manual (Tachometer yaitu antara 0.35-0.4 HANK.Perbedaan terjadi karena pada perhitungan manual, mesin diasumsikan selalu berjalan. Padahal pada kenyataannya terjadi proses dopping (penggantian cone benang. Dapat disimpulkan bahwa sistem CPM telah dapat digunakan untuk mengetahui efisiensi kerja mesin dan hasil produksi secara otomatis. Kata kunci: counter production monitoring, encoder gear, Inductive Proximity Sensor, mikrokontroler, personal komputer.   Abstract A Counter Production Monitoring (CPM system was implemented to calculate automatically a machine speed, a production speed and a total production. This system was employed on a spinning machine in a textile industry to know machine efficiency and a number of thread productions. The system consists of some microcontroller-based hardware and software modules to detect machine rotation. Inductive proximity sensor and encoder gear were installed with a rotary machine shaft in 1 mm distance. A number of machine rotation was calculated from the

  19. Wet counter flow microfine classification in a centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Timmermann, D.; Schoenert, K. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Aufbereitung von Rohstoffen und Reststoffen

    1995-12-31

    This paper reports on the results of research on counter flow classification of {minus}10 {micro}m particles.Two classifiers were designed and constructed, the first semicontinuous and the second fully continuous. The latest version operates continuously with recoveries of fines up to 90% at feed loads of 30 vol.%, separation sharpness x{sub 25}/x{sub 75} up to 0.83, without bypass and cut sizes down to 1.4 {micro}m (x{sub 50} from separation efficiency curve).

  20. Empowering Kinship to Counter Control on Family Discourse in Indonesia

    Directory of Open Access Journals (Sweden)

    Ivanovich Agusta

    2009-12-01

    Full Text Available Indonesian government constructs a discourse on family duringmodernizing Indonesia. A conceptual “father” used to legitimate control of the regime, as well as “state ibuism” (“state mothering” to control especially women. A controlled family discourse is used around political sphere on national election, public administration, family planning, school, etc. State bureaucrats placed at national, provincial, regency, and village levels to control a nuclear family (Westernized type of family pushed for local people. Countering the dominant discourse, local family still integrates kinship based on women power. The actual and discourse of local kinship used for constructing local economy and local politics.

  1. A Nuclear Polariton with Two Entangled Counter-Propagating Branches

    CERN Document Server

    Liao, Wen-Te

    2014-01-01

    A setup for generating the special superposition of a simultaneously forward- and backward-propagating collective excitation in a nuclear sample is studied. We show that by actively manipulating the scattering channels of single x-ray quanta with the help of a normal incidence x-ray mirror, a nuclear polariton which propagates in two opposite directions can be generated. The two counter-propagating polariton branches are entangled by a single x-ray photon. The quantum nature of the nuclear excitation entanglement gives rise to a sub-angstrom wavelength standing wave excitation pattern that can be used as a flexible tool to probe matter dynamically on the atomic scale.

  2. Seeded QED cascades in counter propagating laser pulses

    CERN Document Server

    Grismayer, Thomas; Martins, Joana L; Fonseca, Ricardo; Silva, Luís O

    2015-01-01

    The growth rates of seeded QED cascades in counter propagating lasers are calculated with 2D/3D QED-PIC simulations. The dependence of the growth rate on laser polarisation and intensity are compared with analytical models that support simulations results. The models provide an insight regarding the qualitative trend of the cascade growth when the intensity of the laser field is varied. The results suggest that relativistic pair plasmas and efficient conversion from laser photons to gamma rays can be created with the typical intensities planned to operate on future ultra-intense laser facilities such as ELI or VULCAN.

  3. A lidar equipped with photon counter for measuring stratospheric aerosols

    Science.gov (United States)

    Zhou, Jun; Hu, Huanling

    1991-01-01

    A large lidar system was developed at the Anhui Institute of Optics and Fine Mechanics. It is composed of a high power frequency doubled Nd:YAG laser (120 mJ at 532 nm, 1 mrad), a 651 mm diameter receiving telescope, and a 64 channel photon counter. The lidar observations are controlled by an IBM PC/AT computer. One of the projects is to use the lidar system to make regular observations of stratospheric aerosols. Profiles of scattering ratio have been obtained since November 1989. Meanwhile, an Xe-Cl laser (308 nm wavelength) was assembled to allow the lidar to make measurements of vertical ozone distributions.

  4. Stable counter-rotating vortex pairs in saturable media

    Energy Technology Data Exchange (ETDEWEB)

    Desyatnikov, Anton S. [Nonlinear Physics Centre, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 (Australia)]. E-mail: asd124@rsphysse.anu.edu.au; Mihalache, Dumitru [Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Department of Theoretical Physics, 407 Atomistilor, Magurele-Bucharest 077125 (Romania); Mazilu, Dumitru [Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Department of Theoretical Physics, 407 Atomistilor, Magurele-Bucharest 077125 (Romania); Malomed, Boris A. [Department of Interdisciplinary Studies, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Lederer, Falk [Institute of Solid State Theory and Theoretical Optics, Friedrich-Schiller Universitaet Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

    2007-04-30

    We resolve a controversial issue of the stability of composite vortex solitons in self-focusing saturable nonlinear media. Stable vortex solitons with hidden angular momentum, i.e., composed of counter-rotating beams with topological charges +1 and -1, are found, and their linear-stability region is identified. In contrast, the solitons with explicit vorticity are always unstable against splitting. The predicted linear stability of the hidden-vorticity solitons is achieved in the strong-saturation regime, when the soliton's total power exceeds a certain threshold. The dynamical stability is verified in direct simulations of nonlinear model.

  5. Fabrication of solar cells with counter doping prevention

    Science.gov (United States)

    Dennis, Timothy D; Li, Bo; Cousins, Peter John

    2013-02-19

    A solar cell fabrication process includes printing of dopant sources over a polysilicon layer over backside of a solar cell substrate. The dopant sources are cured to diffuse dopants from the dopant sources into the polysilicon layer to form diffusion regions, and to crosslink the dopant sources to make them resistant to a subsequently performed texturing process. To prevent counter doping, dopants from one of the dopant sources are prevented from outgassing and diffusing into the other dopant source. For example, phosphorus from an N-type dopant source is prevented from diffusing to a P-type dopant source comprising boron.

  6. Real-time reconfigurable counter-propagating beam-traps

    DEFF Research Database (Denmark)

    Tauro, Sandeep; Bañas, Andrew Rafael; Palima, Darwin;

    2010-01-01

    We present a versatile technique that enhances the axial stability and range in counter-propagating (CP) beam-geometry optical traps. It is based on computer vision to track objects in unison with software implementation of feedback to stabilize particles. In this paper, we experimentally...... which simulates biosamples. By working on differences rather than absolute values, this feedback based technique makes CPtrapping nullify many of the commonly encountered pertubations such as fluctuations in the laser power, vibrations due to mechanical instabilities and other distortions emphasizing...

  7. Filamentation instability of counter-streaming laser-driven plasmas

    CERN Document Server

    Fox, W; Bhattacharjee, A; Chang, P -Y; Germaschewski, K; Hu, S X; Nilson, P M

    2013-01-01

    Filamentation due to the growth of a Weibel-type instability was observed in the interaction of a pair of counter-streaming, ablatively-driven plasma flows, in a supersonic, collisionless regime relevant to astrophysical collisionless shocks. The flows were created by irradiating a pair of opposing plastic (CH) foils with 1.8 kJ, 2-ns laser pulses on the OMEGA EP laser system. Ultrafast laser-driven proton radiography was used to image the Weibel-generated electromagnetic fields. The experimental observations are in good agreement with the analytical theory of the Weibel instability and with particle-in-cell simulations.

  8. Filamentation instability in two counter-streaming laser plasmas

    Science.gov (United States)

    Liu, Hui; Dong, Quan-Li; Yuan, Da-Wei; Liu, Xun; Hua, Neng; Qiao, Zhan-Feng; Zhu, Bao-Qiang; Zhu, Jian-Qiang; Jiang, Bo-Bin; Du, Kai; Tang, Yong-Jian; Zhao, Gang; Yuan, Xiao-Hui; Sheng, Zheng-Ming; Zhang, Jie

    2016-12-01

    The filamentation instability was observed in the interaction of two counter-streaming laser ablated plasma flows, which were supersonic, collisionless, and also closely relevant to astrophysical conditions. The plasma flows were created by irradiating a pair of oppositely standing plastic (CH) foils with 1ns-pulsed laser beams of total energy of 1.7 kJ in two laser spots. With characteristics diagnosed in experiments, the calculated features of Weibel-type filaments are in good agreement with measurements. Project supported by the National Natural Science Foundation of China (Grant Nos. 11074297, 11674146, and 11220101002) and the National Basic Research Program of China (Grant No. 2013CBA01500.

  9. 30-ps time resolution with segmented scintillation counter for MEG II

    Science.gov (United States)

    Uchiyama, Y.; Boca, G.; Cattaneo, P. W.; De Gerone, M.; Gatti, F.; Nakao, M.; Nishimura, M.; Ootani, W.; Pizzigoni, G.; Rossella, M.; Simonetta, M.; Yoshida, K.

    2017-02-01

    A new timing detector has been developed to measure ∼50 MeV/c positrons with a time resolution of σt ≃ 30 ps in the MEG II experiment. The detector are segmented into 512 scintillation counters, each of which consists of 120 ×(40 or 50) × 5mm3 size BC-422 and two arrays of six AdvanSiD silicon photomultipliers. The single-counter resolutions are measured to be 70-80 ps. The counter layout is optimized to get the maximum number of hit counters (on average 9 for signal positrons). This multiple-counters measurement leads to a significant improvement in the time resolution down to 30 ps. Using the first one-fourth (128) counters, a pilot run was carried out using the MEG II beam of 7 ×107μ+ / s and the basic functionality was tested.

  10. Alternative modes for optical trapping and manipulation using counter-propagating shaped beams

    DEFF Research Database (Denmark)

    Palima, Darwin; Lindballe, T.B.; Kristensen, M.V.

    2011-01-01

    Counter-propagating beams have enabled the first stable three-dimensional optical trapping of microparticles and this procedure has been enhanced and developed over the years to achieve independent and interactive manipulation of multiple particles. In this work, we analyse counter-propagating sh......Counter-propagating beams have enabled the first stable three-dimensional optical trapping of microparticles and this procedure has been enhanced and developed over the years to achieve independent and interactive manipulation of multiple particles. In this work, we analyse counter......-propagating shaped-beam traps that depart from the conventional geometry based on symmetric, coaxial counter-propagating beams. We show that projecting shaped beams with separation distances previously considered axially unstable can, in fact, enhance the axial and transverse trapping stiffnesses. We also show...... for optical trapping and manipulation using patterned counter-propagating beams, which still remains to be fully tapped....

  11. Value for Money? Problems of Impact Assessment of Counter-radicalization Policies on End Target Groups

    DEFF Research Database (Denmark)

    Lindekilde, Lasse

    2012-01-01

    of this is that assessments of the effectiveness of counter-radicalisation measures and policy responses are either lacking or often methodologically questionable, impairing our understanding of the impacts of counter-radicalisation interventions on targeted communities. The article investigates problems of assessing...... the impact of counter-radicalisation measures using Denmark as case study. It shows how the model of radicalisation underlying the Danish counter-radicalisation efforts translate into multilayered policy objectives and diversified policy solutions, and how the initial academic and official assessments...... of the impact of Danish counter-radicalisation policies on end target groups following is impaired and weakened by common methodological problems and challenges. The article concludes by suggesting some ways ahead for more systematic and valid assessments of the impact of counter-radicalisation policies...

  12. The HERA-B ring imaging Cherenkov counter

    Energy Technology Data Exchange (ETDEWEB)

    Arino, I.; Bastos, J.; Broemmelsiek, D.; Carvalho, J.; Chmeissani, M.; Conde, P.; Davila, J.; Dujmic, D.; Eckmann, R.; Garrido, L.; Gascon, D.; Hamacher, T.; Gorisek, A.; Ivaniouchenkov, I.; Ispirian, M.; Karabekian, S.; Kim, M.; Korpar, S.; Krizan, P. E-mail: peter.krizan@ijs.si; Kupper, S.; Lau, K.; Maas, P.; McGill, J.; Miquel, R.; Murthy, N.; Peralta, D.; Pestotnik, R.; Pyrlik, J.; Ramachandran, S.; Reeves, K.; Rosen, J.; Schmidt-Parzefall, W.; Schwarz, A.; Schwitters, R.F.; Siero, X.; Staric, M.; Stanovnik, A.; Skrk, D.; Zivko, T

    2004-01-11

    The HERA-B RICH uses a radiation path length of 2.8 m in C{sub 4}F{sub 10} gas and a large 24 m{sup 2} spherical mirror for imaging Cherenkov rings. The photon detector consists of 2240 Hamamatsu multi-anode photomultipliers with about 27 000 channels. A 2:1 reducing two-lens telescope in front of each photomultiplier tube increases the sensitive area at the expense of increased pixel size, resulting in a contribution to the resolution which roughly matches that of dispersion. The counter was completed in January of 1999, and its performance has been steady and reliable over the years it has been in operation. The design performance of the Ring Imaging Cherenkov counter was fully reached: the average number of detected photons in the RICH for a {beta}=1 particle was found to be 33 with a single-hit resolution of 0.7 and 1 mrad in the fine and coarse granularity regions, respectively.

  13. The HERA-B ring imaging Cherenkov counter

    Science.gov (United States)

    Ariño, I.; Bastos, J.; Broemmelsiek, D.; Carvalho, J.; Chmeissani, M.; Conde, P.; Davila, J.; Dujmić, D.; Eckmann, R.; Garrido, L.; Gascon, D.; Hamacher, T.; Gorišek, A.; Ivaniouchenkov, I.; Ispirian, M.; Karabekian, S.; Kim, M.; Korpar, S.; Križan, P.; Kupper, S.; Lau, K.; Maas, P.; McGill, J.; Miquel, R.; Murthy, N.; Peralta, D.; Pestotnik, R.; Pyrlik, J.; Ramachandran, S.; Reeves, K.; Rosen, J.; Schmidt-Parzefall, W.; Schwarz, A.; Schwitters, R. F.; Siero, X.; Starič, M.; Stanovnik, A.; Škrk, D.; Živko, T.

    2004-01-01

    The HERA-B RICH uses a radiation path length of 2.8 m in C 4F 10 gas and a large 24 m2 spherical mirror for imaging Cherenkov rings. The photon detector consists of 2240 Hamamatsu multi-anode photomultipliers with about 27 000 channels. A 2:1 reducing two-lens telescope in front of each photomultiplier tube increases the sensitive area at the expense of increased pixel size, resulting in a contribution to the resolution which roughly matches that of dispersion. The counter was completed in January of 1999, and its performance has been steady and reliable over the years it has been in operation. The design performance of the Ring Imaging Cherenkov counter was fully reached: the average number of detected photons in the RICH for a β=1 particle was found to be 33 with a single-hit resolution of 0.7 and 1 mrad in the fine and coarse granularity regions, respectively.

  14. Molecular strategies of plant defense and insect counter-defense

    Institute of Scientific and Technical Information of China (English)

    KEYANZHU-SALZMAN; JIAN-LONGBI; TONG-XIANLIU

    2005-01-01

    The prediction of human population growth worldwide indicates there will be a need to substantially increase food production in order to meet the demand on food supply.This can be achieved in part by the effective management of insect pests. Since plants have co-evolved with herbivorous insects for millions of years, they have developed an array of defense genes to protect themselves against a wide variety of chewing and sucking insects.Using these naturally-occurring genes via genetic engineering represents an environmentally friendly insect pest-control measure. Insects, however, have been actively evolving adaptive mechanisms to evade natural plant defenses. Such evolved adaptability undoubtedly has helped insects during the last century to rapidly overcome a great many humanimposed management practices and agents, including chemical insecticides and genetically engineered plants. Thus, better understanding of the molecular and genetic basis of plant defense and insect counter-defense mechanisms is imperative, not only from a basic science perspective, but also for biotechnology-based pest control practice. In this review, we emphasize the recent advance and understanding of molecular strategies of attack-counterattack and defense-counter-defense between plants and their herbivores.

  15. Infant breathing rate counter based on variable resistor for pneumonia

    Science.gov (United States)

    Sakti, Novi Angga; Hardiyanto, Ardy Dwi; La Febry Andira R., C.; Camelya, Kesa; Widiyanti, Prihartini

    2016-03-01

    Pneumonia is one of the leading causes of death in new born baby in Indonesia. According to WHO in 2002, breathing rate is very important index to be the symptom of pneumonia. In the Community Health Center, the nurses count with a stopwatch for exactly one minute. Miscalculation in Community Health Center occurs because of long time concentration and focus on two object at once. This calculation errors can cause the baby who should be admitted to the hospital only be attended at home. Therefore, an accurate breathing rate counter at Community Health Center level is necessary. In this work, resistance change of variable resistor is made to be breathing rate counter. Resistance change in voltage divider can produce voltage change. If the variable resistance moves periodically, the voltage will change periodically too. The voltage change counted by software in the microcontroller. For the every mm shift at the variable resistor produce average 0.96 voltage change. The software can count the number of wave generated by shifting resistor.

  16. High speed non-latching squid binary ripple counter

    Energy Technology Data Exchange (ETDEWEB)

    Silver, A.H.; Phillips, R.R.; Sandell, R.D.

    1985-03-01

    High speed, single flux quantum (SFQ) binary scalers are important components in superconducting analog-to-digital converters (ADC). This paper reviews the concept for a SQUID ADC and the design of an SFQ binary ripple counter, and reports the simulation of key components, and fabrication and performance of non-latching SQUID scalers and SFQ binary ripple counters. The SQUIDs were fabricated with Nb/Nb/sub 2/O/sub 5//PbIn junctions and interconnected by monolithic superconducting transmission lines and isolation resistors. Each SQUID functioned as a bistable flip-flop with the input connected to the center of the device and the output across one junction. All junctions were critically damped to optimize the pulse response. Operation was verified by observing the dc I-V curves of successive SQUIDs driven by a cw pulse train generated on the same chip. Each SQUID exhibited constant-voltage current steps at 1/2 the voltage of the preceding device as expected from the Josephson voltage-to-frequency relation. Steps were observed only for the same voltage polarity of successive devices and for proper phase bias of the SQUID. Binary frequency division was recorded up to 40GHz for devices designed to operate to 28GHz.

  17. New neutron long-counter on the Lohengrin spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Mathieu, L.; Serot, O.; Litaize, O.; Bail, A. [CEA Cadarache, DENIDER/SPRC/LEPh, 13 - Saint-Paul-Lez-Durance (France); Materna, T.; Faust, H.; Koster, U. [Institut Laue Langevin, rue Jules Horowitz, 38 -Grenoble (France); Jouanne, C. [CEA Saclay, DEN/DANS/DM2S/SERMA/LLPR, 91 (France); Panebianco, S. [CEA Saclay, DSM/IRFU/SPHN/MNM, 91 (France); Rissanen, J. [University of Jyvaskyla (Finland); Simpson, G. [Laboratoire de Physique Subatomique et de Cosmologie, 38 - Grenoble (France)

    2009-07-01

    Few neutrons are emitted by the fission products several seconds to several minutes after fission occurs. These delayed neutrons are crucial for the conduct and safety aspects of nuclear reactors. Delayed neutron emission probabilities (P{sub n} values) are often measured with a set of beta detectors coupled with a neutron long-counter detector ({sup 3}He tubes embedded in a polyethylene matrix). The neutron/beta detection efficiency ratio is then determined experimentally and used to calculate other P{sub n} values. But this gives accurate results only if this ratio is kept constant for all measured nuclei. A new neutron long-counter detector has been built at the Institute Laue Langevin in Grenoble (France) in order to carry out P{sub n} measurements on the Lohengrin mass spectrometer. This detector was designed in order to have a constant efficiency for a wide energy range (from 10 keV to nearly 1 MeV). The results of the first experiment are rather satisfactory although some of the data have too large uncertainties to be useful. In order to improve this, the neutron background has to be reduced and additional shielding will be added to the detector

  18. Monolithic Active Pixel Matrix with Binary Counters (MAMBO) ASIC

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Farah F.; Deptuch, Grzegorz; Shenai, Alpana; Yarema, Raymond J.; /Fermilab

    2010-11-01

    Monolithic Active Matrix with Binary Counters (MAMBO) is a counting ASIC designed for detecting and measuring low energy X-rays from 6-12 keV. Each pixel contains analogue functionality implemented with a charge preamplifier, CR-RC{sup 2} shaper and a baseline restorer. It also contains a window comparator which can be trimmed by 4 bit DACs to remove systematic offsets. The hits are registered by a 12 bit ripple counter which is reconfigured as a shift register to serially output the data from the entire ASIC. Each pixel can be tested individually. Two diverse approaches have been used to prevent coupling between the detector and electronics in MAMBO III and MAMBO IV. MAMBO III is a 3D ASIC, the bottom ASIC consists of diodes which are connected to the top ASIC using {mu}-bump bonds. The detector is decoupled from the electronics by physically separating them on two tiers and using several metal layers as a shield. MAMBO IV is a monolithic structure which uses a nested well approach to isolate the detector from the electronics. The ASICs are being fabricated using the SOI 0.2 {micro}m OKI process, MAMBO III is 3D bonded at T-Micro and MAMBO IV nested well structure was developed in collaboration between OKI and Fermilab.

  19. Photovoltachromic device with a micropatterned bifunctional counter electrode.

    Science.gov (United States)

    Cannavale, Alessandro; Manca, Michele; De Marco, Luisa; Grisorio, Roberto; Carallo, Sonia; Suranna, Gian Paolo; Gigli, Giuseppe

    2014-02-26

    A photovoltachromic window can potentially act as a smart glass skin which generates electric energy as a common dye-sensitized solar cell and, at the same time, control the incoming energy flux by reacting to even small modifications in the solar radiation intensity. We report here the successful implementation of a novel architecture of a photovoltachromic cell based on an engineered bifunctional counter electrode consisting of two physically separated platinum and tungsten oxide regions, which are arranged to form complementary comb-like patterns. Solar light is partially harvested by a dye-sensitized photoelectrode made on the front glass of the cell which fully overlaps a bifunctional counter electrode made on the back glass. When the cell is illuminated, the photovoltage drives electrons into the electrochromic stripes through the photoelectrochromic circuit and promotes the Li(+) diffusion towards the WO3 film, which thus turns into its colored state: a photocoloration efficiency of 17 cm(2) min(-1) W(-1) at a wavelength of 650 nm under 1.0 sun was reported along with fast response (coloration time photovoltaic functionality was also retained due to the copresence of the independently switchable micropatterned platinum electrode.

  20. Counter rotating type hydroelectric unit suitable for tidal power station

    Energy Technology Data Exchange (ETDEWEB)

    Kanemoto, T [Faculty of Engineering, Kyushu Institute of Technology, Sensui 1-1, Tobata, Kitakyushu 804-8550 (Japan); Suzuki, T, E-mail: turbo@tobata.isc.kyutech.ac.j [Graduate School of Engineering, Kyushu Institute of Technology, Sensui 1-1, Tobata, Kitakyushu 804-8550 (Japan)

    2010-08-15

    The counter rotating type hydroelectric unit, which is composed of the axial flow type tandem runners and the peculiar generator with double rotational armatures,was proposed to utilize effectively the tidal power. In the unit, the front and the rear runners counter drive the inner and the outer armatures of the generator, respectively. Besides, the flow direction at the rear runner outlet must coincide with the flow direction at the front runner inlet, because the angular momentum through the rear runner must coincides with that through the front runner. That is, the flow runs in the axial direction at the rear runner outlet while the axial inflow at the front runner inlet. Such operations are suitable for working at the seashore with rising and falling tidal flows, and the unit may be able to take place of the traditional bulb type turbines. The tandem runners were operated at the on-cam conditions, in keeping the induced frequency constant. The output and the hydraulic efficiency are affected by the adjustment of the front and the blade setting angles. The both optimum angles giving the maximum output and/or efficiency were presented at the various discharges/heads. To promote more the tidal power generation by this type unit, the runners were also modified so as to be suitable for both rising and falling flows. The hydraulic performances are acceptable while the output is determined mainly by the trailing edge profiles of the runner blades.

  1. Microstructure and properties of vacuum counter-pressure cast aluminum alloy

    OpenAIRE

    YAN Qing-song; Yu, Huan; WEI Bo-kang

    2006-01-01

    The microstructure and properties of vacuum counter-pressure cast aluminum alloy were studied. Results indicated that under the condition of vacuum counter-pressure, liquid melts fill mould cavity under the vacuum and crystallize under high pressure which have very good effect on nucleation and solidification feeding. Compared with gravity casting, the microstructure of vacuum counter-pressure cast aluminum alloy is much finer and more uniformly distributed. Mechanical properties of vacuum co...

  2. Anthocyanin-sensitized solar cells using carbon nanotube films as counter electrodes

    Science.gov (United States)

    Zhu, Hongwei; Zeng, Haifeng; Subramanian, Venkatachalam; Masarapu, Charan; Hung, Kai-Hsuan; Wei, Bingqing

    2008-11-01

    Carbon nanotube (CNT) films have been used as counter electrodes in natural dye-sensitized (anthocyanin-sensitized) solar cells to improve the cell performance. Compared with conventional cells using natural dye electrolytes and platinum as the counter electrodes, cells with a single-walled nanotube (SWNT) film counter electrode show comparable conversion efficiency, which is attributed to the increase in short circuit current density due to the high conductivity of the SWNT film.

  3. Nolan-Pollak type CN counters in the Vienna aerosol workshop

    Science.gov (United States)

    Gras, J. L.; Podzimek, J.; O'Connor, T. C.; Enderle, K.-H.

    Three "standard" Nolan-Pollak (N-P) and a modified N-P design condensation nucleus (CN) counters were included in the Vienna Workshop on Intercomparison of Condensation Nuclei and Aerosol Particle counters. These counters came from diverse backgrounds, namely programs in USA, Europe and Australia. In this work, principles of the operation and previous history of calibration of the N-P expansion counter are briefly reviewed and comparisons between the particular counters used in the workshop are presented and discussed. Counting agreement was found to be very good between the N-P counters, typically better than ±12% for a range of aerosol sizes and compositions from a minimum diameter of 4 nm. The independently calibrated GIV CNC-440 (modified N-P type counter) also agreed well with the N-P counters. The minimum size sensitivity of the N-P counter was examined showing a lower detection limit for insoluble (Ag) particles of around 2.6±0.3 nm diameter.

  4. DESIGN OF MODULO-6-COUNTER USING CARBON NANOTUBE FIELD EFFECT TRANSISTOR

    Directory of Open Access Journals (Sweden)

    V.Saravanan

    2012-11-01

    Full Text Available In many digital applications like digital clock, frequency divider circuit and nano applications etc., designing of low power modulo counters is highly desirable. Designing of such a counters using existing technology i.e., CMOS technology has the limitations in-terms of power consumption, device scaling limitations andfabrications difficulties in nanometre range. This paper proposes the new design technique for modulo counters using the carbon nanotube field effect transistor (CNTFET. Counter performance is analyzed interms of speed and power consumption. This paper also analyses carbon nanotube (CNT types, how the carbon nanotube is formed, and scaling limitations of the CMOS technology in nanometre range.

  5. Dynamics of flexible counter-ions in conducting polyaniline a quasielastic neutron-scattering study

    CERN Document Server

    Bee, M; Djurado, D; Marque, D; Combet, J; Rannou, P; Dufour, B

    2002-01-01

    Conducting polyaniline protonated with sulphonic flexible counter-ions was investigated by quasielastic incoherent neutron scattering. In addition to their role in electrical properties, the flexible counter-ions also increase the elasticity of the samples. As in the case of more rigid counter-ions, polymer chains appear as very stiff objects whose dynamics is completely outside the investigated time scale. Conversely, the counter-ion dynamics was proved to be of major importance in charge transport since a dynamical transition is observed precisely in the temperature range where the electronic properties change from a metallic to a semiconducting regime. (orig.)

  6. Waste Management Practices among Counter Service Restaurants in Batangas City, Philippines

    Directory of Open Access Journals (Sweden)

    Billy T. Festijo

    2013-08-01

    Full Text Available The study looked into the extent of the proper waste management of the counter service restaurants in Batangas City, Philippines. The waste management of counter service restaurant highlighted on reducing the food establishment demand for virgin raw materials through increasing waste prevention and recycling. The problem encountered of the counter service restaurant agrees on the government policy that was implementing in our country. The proposed plan of action will help the counter service restaurant may serve as a guide in minimization of the waste management.

  7. CoS-Graphene Composite Counter Electrode for High Performance Dye-Sensitized Solar Cell.

    Science.gov (United States)

    Wang, Fen; Wu, Congcong; Tan, Yuan; Jin, Tetsuro; Chi, Bo; Pu, Jian; Jian, Li

    2015-02-01

    CoS-graphene composite counter electrode for dye-sensitized solar cell (DSSC) was prepared by coating hydrothermal synthesized CoS with graphene onto the FTO conductive glass. SEM shows that CoS particles are uniformly dispersed in the graphene. The result confirms that the prepared composite counter electrode is of highly electrocatalytic activity towards iodine reduction, which is even better than Pt electrode. And cyclic voltammetry measurement also shows that the composite counter electrode has good stability after 100 scan cycles. DSSC with CoS-graphene as composite counter electrode achieves a maximum power conversion efficiency of 6.31%, which is better than Pt electrode.

  8. Counter-Productive Counter-Terrorism. How is the dysfunctional discourse of Prevent failing to restrain radicalisation?

    Directory of Open Access Journals (Sweden)

    Lauren Powell

    2016-09-01

    Full Text Available This paper explores why the Prevent strand of the UK Government’s counter-terrorism strategy, CONTEST, is failing to achieve success in reducing radicalisation of young Muslims. By refusing to engage with extremists, and denying ‘extreme’ ideas a platform for expression, this paper will explain how the importance of cultural-linguistic epistemologies, and their role in extremism, has been overlooked. Rather than striving to understand how socio-political factors influence one’s reading of religious doctrines or interpretation of ideology, Prevent understands ideology to be the core radicalising agent, used by influential figures who can exploit the grievances of the vulnerable. The problematic repercussions of this will be addressed throughout, highlighting the various, and extensive, criticisms that Prevent has faced from academics, practitioners and commentators – primarily that it is counter-productive. The importance of the post-9/11 neoconservative paradigm in underpinning Prevent will be explained, but a Neo-Weberian approach, as a better lens through which to understand radicalisation, will be proposed, to ultimately trump the simplistic, yet currently dominant, ‘Conveyor Belt’ theory. Based on this, recommendations are made for an improved Prevent, rooted in the notion that radicalisation, extremism, or terrorism cannot be prevented, without knowing the motives, the views, and the assumptions of the radicals, the extremists, and those vulnerable to engaging with them.

  9. An Improved Polar-Coordinate Navigation System with the Establishment of Electronic Counter-counter Measures Capabilities

    Directory of Open Access Journals (Sweden)

    Qiang Zhang

    2013-01-01

    Full Text Available With easy-to-be-disposed architecture and premium navigation performances, polar-coordinate navigationsystem (PCNS is still widely utilized by modern military navigation systems. Unfortunately, PCNS has very poor electronic counter-counter measures (ECCM performances, due to the lack of electronic warfare (EW considerations during its initial system design. To solve this problem, an improved PCNS (Imp-PCNS is proposed in this paper to introduce ECCM capabilities to PCNS. The low probability of intercept (LPI waveforms are utilized instead of regular pulses to reduce the probability of hostile interception. Both the bandwidth and the transmitted power of LPI are designed to generate the signals submerged under the thermal noises at the front ends of enemy receivers. Finally, a kinematic bearing method is proposed to dramatically reduce the possibility of intercept. The principle of kinematic bearing is analyzed in detail. An undistorted observed geometric position (OGP, which is independent ofthe deviation of observing angle, is achieved by controlling the rotation of the antenna array of PCNS beacon.Defence Science Journal, 2013, 63(1, pp.114-118, DOI:http://dx.doi.org/10.14429/dsj.63.2519

  10. An Improved Polar-Coordinate Navigation System with the Establishment of Electronic Counter-counter Measures Capabilities

    Directory of Open Access Journals (Sweden)

    Zhang Qiang

    2013-01-01

    Full Text Available With easy-to-be-disposed architecture and premium navigation performances, polar-coordinate navigation system (PCNS is still widely utilized by modern military navigation systems. Unfortunately, PCNS has very poor electronic counter-counter measures (ECCM performances, due to the lack of electronic warfare (EW considerations during its initial system design. To solve this problem, an improved PCNS (Imp-PCNS is proposed in this paper to introduce ECCM capabilities to PCNS. The low probability of intercept (LPI waveforms are utilized instead of regular pulses to reduce the probability of hostile interception. Both the bandwidth and the transmitted power of LPI are designed to generate the signals submerged under the thermal noises at the front ends of enemy receivers. Finally, a kinematic bearing method is proposed to dramatically reduce the possibility of intercept. The principle of kinematic bearing is analyzed in detail. An undistorted observed geometric position (OGP, which is independent of the deviation of observing angle, is achieved by controlling the rotation of the antenna array of PCNS beacon.

  11. Assessing Counter-Terrorism field training with multiple behavioral measures.

    Science.gov (United States)

    Spiker, V Alan; Johnston, Joan H

    2013-09-01

    Development of behavioral pattern recognition and analysis skills is an essential element of Counter-Terrorism training, particularly in the field. Three classes of behavioral measures were collected in an assessment of skill acquisition during a US Joint Forces Command-sponsored course consisting of Combat Tracking and Combat Profiling segments. Measures included situational judgment tests, structured behavioral observation checklists, and qualitative assessments of the emergence of specific knowledge-skills-attitudes over the course of the training. The paper describes statistical evidence across the three types of measures that indicate that behavioral pattern recognition and analysis skills were successfully acquired by most students (a mix of Army and civilian law enforcement personnel) during the field training exercises. Implications for broader training of these critical skills are also discussed.

  12. Source Lines Counter (SLiC) Version 4.0

    Science.gov (United States)

    Monson, Erik W.; Smith, Kevin A.; Newport, Brian J.; Gostelow, Roli D.; Hihn, Jairus M.; Kandt, Ronald K.

    2011-01-01

    Source Lines Counter (SLiC) is a software utility designed to measure software source code size using logical source statements and other common measures for 22 of the programming languages commonly used at NASA and the aerospace industry. Such metrics can be used in a wide variety of applications, from parametric cost estimation to software defect analysis. SLiC has a variety of unique features such as automatic code search, automatic file detection, hierarchical directory totals, and spreadsheet-compatible output. SLiC was written for extensibility; new programming language support can be added with minimal effort in a short amount of time. SLiC runs on a variety of platforms including UNIX, Windows, and Mac OSX. Its straightforward command-line interface allows for customization and incorporation into the software build process for tracking development metrics. T

  13. Cloud Condensation Nuclei Particle Counter (CCN) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Uin, Janek [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-04-01

    The Cloud Condensation Nuclei Counter—CCN (Figure 1) is a U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility instrument for measuring the concentration of aerosol particles that can act as cloud condensation nuclei [1, 2]. The CCN draws the sample aerosol through a column with thermodynamically unstable supersaturated water vapor that can condense onto aerosol particles. Particles that are activated, i.e., grown larger in this process, are counted (and sized) by an Optical Particle Counter (OPC). Thus, activated ambient aerosol particle number concentration as a function of supersaturation is measured. Models CCN-100 and CCN-200 differ only in the number of humidifier columns and related subsystems: CCN-100 has one column and CCN-200 has two columns along with dual flow systems and electronics.

  14. Control Modules for Scintillation Counters in the SPS Experimental Areas

    CERN Document Server

    Baribaud, Guy; Cojan, A; Ferri, G; Fullerton, J; Manarin, A; Spanggaard, J

    2001-01-01

    The hardware used in the SPS Experimental Areas to control the beam instrumentation electronics and mechanics of the particle detectors is based on CAMAC and NIM modules. The maintenance of this hardware now presents very serious problems. The modules used to operate the Experimental Areas are numerous and older than 20 years so many of them cannot be repaired any more and CAMAC is no longer well supported by industry. The fast evolution of technology and a better understanding of the detectors allow a new equipment-oriented approach, which is more favourable for maintenance purposes and presents fewer data handling problems. VME and IP Modules were selected as standard components to implement the new electronics to control and read out the particle detectors. The first application implemented in this way concerns the instrumentation for the Scintillation Counters (formerly referred to as triggers). The fundamental options and the design features will be presented.

  15. Counter-forensics in machine learning based forgery detection

    Science.gov (United States)

    Marra, Francesco; Poggi, Giovanni; Roli, Fabio; Sansone, Carlo; Verdoliva, Luisa

    2015-03-01

    With the powerful image editing tools available today, it is very easy to create forgeries without leaving visible traces. Boundaries between host image and forgery can be concealed, illumination changed, and so on, in a naive form of counter-forensics. For this reason, most modern techniques for forgery detection rely on the statistical distribution of micro-patterns, enhanced through high-level filtering, and summarized in some image descriptor used for the final classification. In this work we propose a strategy to modify the forged image at the level of micro-patterns to fool a state-of-the-art forgery detector. Then, we investigate on the effectiveness of the proposed strategy as a function of the level of knowledge on the forgery detection algorithm. Experiments show this approach to be quite effective especially if a good prior knowledge on the detector is available.

  16. A lens-coupled scintillation counter in cryogenic environment

    CERN Document Server

    Stoykov, A; Amato, A; Bartkowiak, M; Konter, J A; Rodriguez, J; Sedlak, K

    2011-01-01

    In this work we present an elegant solution for a scintillation counter to be integrated into a cryogenic system. Its distinguishing feature is the absence of a continuous light guide coupling the scintillation and the photodetector parts, operating at cryogenic and room temperatures respectively. The prototype detector consists of a plastic scintillator with glued-in wavelength-shifting fiber located inside a cryostat, a Geiger-mode Avalanche Photodiode (G-APD) outside the cryostat, and a lens system guiding the scintillation light re-emitted by the fiber to the G-APD through optical windows in the cryostat shields. With a 0.8mm diameter multiclad fiber and a 1mm active area G-APD the coupling efficiency of the "lens light guide" is about 50%. A reliable performance of the detector down to 3K is demonstrated.

  17. Management of the Extreme Events: Countering International Terrorism

    Directory of Open Access Journals (Sweden)

    Dr. Cristian Barna

    2011-12-01

    Full Text Available After the terrorism attacks of September 11, 2001, there is recognition by both the public and private sectors that one needs to rethink our strategy for dealing with these low probability but extreme consequence events. September 11, 2001 attacks against the United States raised numerous questions related to counter-terrorism, foreign policy, as well as national security in the United States and abroad. They also raised the fundamental question of who should pay for losses due to terrorism.The question of who should pay for terrorism risk prevention and sustainable coverage within a country is likely to be seen first as a matter of collective responsibility that each country has to consider – a societal choice

  18. Performance of an active well coincidence counter for HEU samples

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, Francesca, E-mail: fra.ferrari@gmail.co [European Commission, Joint Research Centre, Institute for the Protection and the Security of the Citizen (IPSC), 21020 Ispra (Italy); Peerani, Paolo, E-mail: paolo.peerani@jrc.i [European Commission, Joint Research Centre, Institute for the Protection and the Security of the Citizen (IPSC), 21020 Ispra (Italy)

    2010-10-15

    Neutron coincidence counting is the reference NDA technique used in nuclear safeguards to measure the mass of nuclear material in samples. For high-enriched uranium (HEU) samples active neutron interrogation is generally performed and the most common device used by nuclear inspectors is the Active Well Coincidence Counter (AWCC). Within her master thesis at the Polytechnic of Milan, the first author performed an intensive study on the characteristics and performances of the AWCC in order to assess the {sup 235}U mass in HEU oxide samples at the PERLA laboratory of JRC. The work has been summarised in this paper that starts with the optimisation of the use of AWCC for nuclear safeguards, describing the calibration procedure, reporting results of a series of verification measurements, summarising the performances that can be obtained with this instruments during inspections at fuel production plants and concluding with the discussion of uncertainties related to these measurements.

  19. Insect Counter-Adaptations to Plant Cyanogenic Glucosides

    DEFF Research Database (Denmark)

    Pentzold, Stefan

    Cyanogenic glucosides are ancient and widespread defence compounds that are used by plants to fend off non-adapted insect herbivores. After insect herbivory and plant tissue damage, cyanogenic glucosides come into contact with compartmentalised plant β-glucosidases, resulting in the release...... of toxic hydrogen cyanide. Such a binary system of components that are chemically inert when separated is also referred to as two-component plant defence. Since the co-evolution of cyanogenic plants and insect herbivores has continued for several hundred million years, some specialised herbivores have...... adapted and gained the ability to feed on cyanogenic plants. Moreover, a few specialists are even able to sequester cyanogenic glucosides into specialised tissues, often for use in their own defence. However, insect counter-adaptations to overcome plant cyanogenic glucosides are largely unknown...

  20. The cultural counter-discourse on Lisbon’s slums

    Directory of Open Access Journals (Sweden)

    Luana Loria

    2016-09-01

    Full Text Available The urban periphery —slums— of Lisbon will be observed as the space of manifestation of the counter-discourse of contemporaneity with respect to the symbolic and cultural imaginary of Portugal. The music, as a production of the residents of the slums, particularly rap music, and contemporary cinema, as a mean of representation of these places, have contributed to the decentralization of the national imaginary and to the deconstruction of Portugalidade, showing the changes in social and cultural profile of the country in recent decades . To address this issue, we will focus on the critical production of some theorists such as Stuart Hall and Roger Haesbaert which have reflected respectively on the theme of diaspora and the concept of reterritorialization.

  1. Why Counter-terrorism Breeds Yet More Terrorism

    Institute of Scientific and Technical Information of China (English)

    Shen Jiru

    2006-01-01

    @@ The global campaign against terror has achieved considerable success over the past five years since the events of 9/11. The Taliban forces in Afghanistan have been destroyed and Al-Qeda has received a devastating blow. In Russia, Chechen secessionist terrorist forces have also suffered heavy losses. Nevertheless, the major terrorist attacks that took place in the UK, Spain, Russia, Iraq, India and Indonesia clearly demonstrate that terrorism has not yet disappeared.Terrorist attacks are on the increase, the targets are becoming more varied, and the methods more covert and more violent. Terrorist groups and organizations have become better organized in their activities and there is a trend towards the use of high-tech in the attacks.Some world public media refers to these phenomena as "counter-terrorism leading to yet more terrorism". Therefore, two fundamental questions may be posed to all countries throughout the world: What are the roots of terrorism? How can terrorism be eradicated?

  2. Hollow platinum alloy tailored counter electrodes for photovoltaic applications

    Science.gov (United States)

    Li, Pinjiang; Zhang, Yange; Fa, Wenjun; Yang, Xiaogang; Wang, Liang

    2017-08-01

    Without sacrifice of photovoltaic performances, low-platinum alloy counter electrodes (CEs) are promising in bringing down the fabrication cost of dye-sensitized solar cells (DSSCs). We present here the realization of ZnO nanostructure assisted hollow platinum-nickel (PtNi) alloy microstructure CEs with a simple hydrothermal methods and maximization of electrocatalytic behaviors by tuning Zn precursors. The maximal power conversion efficiency is up to 8.74% for the liquid-junction dye-sensitized solar cells with alloyed PtNi0.41 electrode, yielding a 37.6% cell efficiency enhancement in comparison with pristine solar cell from planar Pt electrode. Moreover, the dissolution-resistant and charge-transfer abilities toward I-/I3- redox electrolyte have also been markedly enhanced due to competitive dissolution reactions and alloying effects.

  3. Nuclear counter effect and pi-e misidentification

    CERN Document Server

    Zürcher, D

    2000-01-01

    The e sup+-/pi sup+- discrimination within the CMS(1) ECAL is investigated using GEANT simulations and the 1998 test beam results. If one takes into account the energy left in the ECAL crystals alone (i.e. without read-out effects), the probability that a pi sup+- leaves more than 95% of its initial energy decreases from about 0.01% for 10 GeV to about 0.001% for 50 GeV. The Nuclear Counter Effect within the Avalanche Photo-Diodes (APD) enhances the probability of an electron misidentification. With the expected value of this effect (approx 100 MeV), this probability appears then to be between 0.2% and 0.01% for initial momenta varying, respectively, between 5 and 50 GeV. Important consequences of the pion-electron misidentification could appear in the form of new possible backgrounds for physics channels.

  4. Counter-Terrorism Contributions from the National Labs

    Science.gov (United States)

    Davis, Jay

    2002-04-01

    The DOD and NNSA laboratories have significant technical capabilities that can contribute to counter-terrorism and homeland security. Maximizing those contributions, however, requires that laboratory staff engage the doctrinal and operational issues of these problems as well. The broader interagency community needs support in these components of the problem as much as in the technical components. The speaker's experiences as director of the DoD Defense Threat Reduction Agency, established in 1998 to address DoD's role in defense against weapons of mass destruction in all venues, have given him a somewhat unique perspective on this problem. Examples of issues identified in scenario play at Cabinet level in the last Admistration will be given to illustrate the breadth of this problem, as will the speaker's assessment of the grand challenges in deterring use of WMD against the Homeland.

  5. Detection of single photons with THickGEM-based counters

    Energy Technology Data Exchange (ETDEWEB)

    Alexeev, M. [INFN, Sezione di Torino and University of East Piemonte, Alessandria (Italy); Barbosa, F. [I3N - Physics Department, University of Aveiro (Portugal); Birsa, R. [INFN, Sezione di Trieste, Trieste (Italy); Bradamante, F.; Bressan, A. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Chiosso, M. [INFN, Sezione di Torino and University of Torino, Torino (Italy); Ciliberti, P. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Dalla Torre, S. [INFN, Sezione di Trieste, Trieste (Italy); Denisov, O. [INFN, Sezione di Torino, Torino (Italy); Duic, V. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Ferrero, A. [INFN, Sezione di Torino and University of Torino, Torino (Italy); Finger, M.; Finger, M. [Charles University, Praga (Czech Republic); JINR, Dubna (Russian Federation); Fischer, H. [Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); Giorgi, M. [INFN, Sezione di Trieste and University of Trieste, Trieste (Italy); Gobbo, B.; Gregori, M. [INFN, Sezione di Trieste, Trieste (Italy); Heinsius, F.H.; Herrmann, F.; Koenigsmann, K. [Universitaet Freiburg, Physikalisches Institut, Freiburg (Germany); and others

    2012-12-11

    Cherenkov imaging counters requiring large photosensitive areas, the capability to stand high rates and to operate in magnetic field environments could benefit from the use of photon detectors based on THick Gaseous Electron Multiplier (THGEM) coupled to a solid state CsI photo-cathode. A systematic study of the THGEM detector response as a function of its geometrical parameters and electrodes' applied voltage has been performed. Dedicated electrostatic calculations to optimize the detector design have been accomplished. Data obtained from small photon detector prototypes operating in single photon detection mode are presented and discussed. In particular the key aspect of photo-electron extraction from the photo-cathode surface is investigated via the timing spectrum response of the detector for different electric field conditions at the photo-cathode: a comparison of the measured time distributions and the simulation results is illustrated.

  6. A lens-coupled scintillation counter in cryogenic environment

    Energy Technology Data Exchange (ETDEWEB)

    Stoykov, A; Scheuermann, R; Amato, A; Bartkowiak, M; Konter, J A; Rodriguez, J; Sedlak, K, E-mail: alexey.stoykov@psi.ch [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

    2011-02-01

    In this work we present an elegant solution for a scintillation counter to be integrated into a cryogenic system. Its distinguishing feature is the absence of a continuous light guide coupling the scintillation and the photodetector parts, operating at cryogenic and room temperatures respectively. The prototype detector consists of a plastic scintillator with glued-in wavelength-shifting fiber located inside a cryostat, a Geiger-mode Avalanche Photodiode (G-APD) outside the cryostat, and a lens system guiding the scintillation light re-emitted by the fiber to the G-APD through optical windows in the cryostat shields. With a 0.8 mm diameter multiclad fiber and a 1 mm active area G-APD the coupling efficiency of the 'lens light guide' is about 50%. A reliable performance of the detector down to 3 K is demonstrated.

  7. [Health care consumers about over-the-counter drugs].

    Science.gov (United States)

    Burger, David M

    2014-01-01

    Dutch consumers can now purchase 'over-the-counter drugs' (OTCs) at three distribution channels: (a) the pharmacy; (b) the chemist; (c) other sales outlets such as supermarkets and petrol stations. However, little is known about whether consumers consider themselves and others to have adequate knowledge to purchase OTCs in relative freedom. During a recent study, members of the Healthcare Consumer Panel of the Netherlands Institute for Health Services Research completed a survey on freely available analgesics. These consumers were very confident of their personal skills in handling OTCs responsibly. However, they had less confidence in how others would deal with OTCs. Regarding the wider availability of OTCs, only 1-8% believed it would be preferable to have these drugs available in the supermarket or petrol station, depending on the type and frequency of side effects of the medication. The government would be wise in conducting this type of qualitative study before measures are taken for wider availability of medicines.

  8. Consumer knowledge of over-the-counter phenazopyridine.

    Science.gov (United States)

    Shi, Chih-Wen; Asch, Steven M; Fielder, Eve; Gelberg, Lillian; Nichol, Michael B

    2004-01-01

    Effective use of over-the-counter (OTC) medications depends on purchasers' knowledge of their indications. This study examines consumer knowledge regarding the urinary tract analgesic phenazopyridine, which recently became available without prescription. We conducted a cross-sectional survey of a stratified cluster random sample of purchasers of OTC phenazopyridine (N = 434) in 31 Los Angeles retail pharmacies. The response rate was 58%. Only 42% correctly characterized the likely cause of their symptoms, and only 57% correctly characterized the action of the drug. Worse consumer knowledge was associated with nonwhite race, first-time use, and less contact with health providers. Many consumers possess poor knowledge about phenazopyridine, potentially leading to undertreatment, especially in groups with worse access to care.

  9. Counter unmanned aerial system testing and evaluation methodology

    Science.gov (United States)

    Kouhestani, C.; Woo, B.; Birch, G.

    2017-05-01

    Unmanned aerial systems (UAS) are increasing in flight times, ease of use, and payload sizes. Detection, classification, tracking, and neutralization of UAS is a necessary capability for infrastructure and facility protection. We discuss test and evaluation methodology developed at Sandia National Laboratories to establish a consistent, defendable, and unbiased means for evaluating counter unmanned aerial system (CUAS) technologies. The test approach described identifies test strategies, performance metrics, UAS types tested, key variables, and the necessary data analysis to accurately quantify the capabilities of CUAS technologies. The tests conducted, as defined by this approach, will allow for the determination of quantifiable limitations, strengths, and weaknesses in terms of detection, tracking, classification, and neutralization. Communicating the results of this testing in such a manner informs decisions by government sponsors and stakeholders that can be used to guide future investments and inform procurement, deployment, and advancement of such systems into their specific venues.

  10. Examination of Over-the-Counter Drug Misuse Among Youth

    Directory of Open Access Journals (Sweden)

    Erin J. Farley

    2010-10-01

    Full Text Available This study examined the prevalence of intentional over-the-counter (OTC drug misuse among teens and the relationship between OTC drug misuse and the misuse of other substances including illicit prescription drugs. Ten percent of 8th graders reported past year use of OTC drugs to get high. Misuse was more common among females than males. Among students who reported past year OTC drug misuse, the three most commonly reported past year drug use included pain relievers (56.2%, sedatives (48.3% and stimulants (45.8%. Logistic regression analysis revealed females were 1.5 times more likely than males to report past year OTC drug use. In addition, past year OTC drug misuse was more common among those who had reported using cigarettes, alcohol, albuterol, inhalants, illicit pain relievers, illicit stimulants, and cocaine.

  11. Countering Radicalisation of Muslim Community Opinions on the EU Level

    Directory of Open Access Journals (Sweden)

    Zięba Aleksandra

    2015-12-01

    Full Text Available The paper explores selected factors influencing the process of radicalisation leading to the use of political violence and terror by the Muslim minorities living in the European Union member states. Internal and external catalysts conditioning this process and methods of their analysis have been presented. The second section examines various counter-radicalisation and de-radicalisation efforts of the EU. The authors analysed the multidimensional European Union policy in the area of counteracting radicalisation for empowering the population and member states in preventing the radicalisation and recruitment to terrorism and emphasising the role of social partners and local authorities. Also, the promotion of good practices for combating radicalisation, developed under the auspices of the multidisciplinary Radicalisation Awareness Network (RAN is presented.

  12. Conflict and complexity countering terrorism, insurgency, ethnic and regional violence

    CERN Document Server

    Bar-Yam, Yaneer; Minai, Ali

    2015-01-01

    Complexity science affords a number of novel tools for examining terrorism, particularly network analysis and NK-Boolean fitness landscapes as well as other tools drawn from non-linear dynamical systems modeling. This book follows the methodologies of complex adaptive systems research in their application to addressing the problems of terrorism, specifically terrorist networks, their structure and various methods of mapping and interdicting them as well as exploring the complex landscape of network-centric and irregular warfare. A variety of new models and approaches are presented here, including Dynamic Network Analysis, DIME/PMESII models, percolation models and emergent models of insurgency. In addition, the analysis is informed by practical experience, with analytical and policy guidance from authors who have served within the U.S. Department of Defense, the British Ministry of Defence as well as those who have served in a civilian capacity as advisors on terrorism and counter-terrorism.

  13. Synthesis of energy-efficient counters implemented in PLD circuits

    Science.gov (United States)

    Kulisz, Józef; Nawrot, Radosław; Kania, Dariusz

    2016-12-01

    The paper presents a comparison of four methods of implementing sequential circuits in Programmable Logic Devices in respect of dissipated power. Objective of the research was to investigate influence of different methods of "disabling" the clock signal on the dynamic power consumed by the circuit. The comparison is carried out using simple counter circuits, i. e. circuits the algorithm of which is described by linear graphs. However, the presented considerations are general, and can be applied to any sequential circuit. Results of simulation tests show that the method based on clock gating is the most efficient one, and it leads to significant reduction of the dissipated dynamic power. The authors also propose a simple modification of global clock network structures, to facilitate clock gating.

  14. Defined solid-angle counter with variable geometry

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Torano, E. [Laboratorio de Metrologia de Radiaciones Ionizantes, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain)], E-mail: e.garciatorano@ciemat.es; Duran Ramiro, T. [Laboratorio de Metrologia de Radiaciones Ionizantes, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain); Burgos, C. [Division de Infraestrutura General Tecnica, CIEMAT, Madrid (Spain); Begona Ahedo, M. [Unidad de Ingenieria y Obras, CIEMAT, Madrid (Spain)

    2008-06-15

    We describe a defined solid-angle counter for the standardization of radioactive sources of alpha-particle emitters. It has been built with the aim of combining good counting efficiencies, low uncertainties and flexibility of operation. The distance between source and detector can be changed in a continuous way with a precision guide and a ball screw from 8 to 19 cm, which correspond to counting efficiencies between 0.023 and 0.004 for small size sources. A linear encoder allows the accurate determination of the source position. Alpha spectra of the sources are measured with an implanted silicon detector with an active area of 2000 mm{sup 2}. Uncertainties, excluding counting statistics, are below 0.1%.

  15. Construction of a BioFluorescence Optical Particle Counter

    Science.gov (United States)

    Greaney, R.

    2009-04-01

    A bioaerosol fluorescence detection system is being constructed using an ellipsoid reflector based optical particle counter. The flux measuring device is to size submicron marine spray aerosol particles smaller than 100 nm in diameter. It will simultaneously non-destructively excite and detect fluorescence from organic matter contained in the aerosol. Chlorophyll-a is the primary fluorophor target, used as a marker for detecting phytoplankton (or derivatives thereof) in the particles. Particles have been sized to 167 nm in diameter and fluorescence detection testing is underway. The device will aid the quantification and identification of this organic material contained in marine spray aerosols, providing improved inputs into climate models and air quality assessments.

  16. Compact multiwire proportional counters for the detection of fission fragments.

    Science.gov (United States)

    Jhingan, Akhil; Sugathan, P; Golda, K S; Singh, R P; Varughese, T; Singh, Hardev; Behera, B R; Mandal, S K

    2009-12-01

    Two large area multistep position sensitive (two dimensional) multiwire proportional counters have been developed for experiments involving study of fission dynamics using general purpose scattering chamber facility at IUAC. Both detectors have an active area of 20x10 cm(2) and provide position signals in horizontal (X) and vertical (Y) planes, timing signal for time of flight measurements and energy signal giving the differential energy loss in the active volume. The design features are optimized for the detection of low energy heavy ions at very low gas pressures. Special care was taken in setting up the readout electronics, constant fraction discriminators for position signals in particular, to get optimum position and timing resolutions along with high count rate handling capability of low energy heavy ions. A custom made charge sensitive preamplifier, having lower gain and shorter decay time, has been developed for extracting the differential energy loss signal. The position and time resolutions of the detectors were determined to be 1.1 mm full width at half maximum (FWHM) and 1.7 ns FWHM, respectively. The detector could handle heavy ion count rates exceeding 20 kHz without any breakdown. Time of flight signal in combination with differential energy loss signal gives a clean separation of fission fragments from projectile and target like particles. The timing and position signals of the detectors are used for fission coincidence measurements and subsequent extraction of their mass, angular, and total kinetic energy distributions. This article describes systematic study of these fission counters in terms of efficiency, time resolution, count rate handling capability, position resolution, and the readout electronics. The detector has been operated with both five electrode geometry and four electrode geometry, and a comparison has been made in their performances.

  17. Dynamic Monitoring of Cleanroom Fallout Using an Air Particle Counter

    Science.gov (United States)

    Perry, Radford

    2011-01-01

    The particle fallout limitations and periodic allocations for the James Webb Space Telescope are very stringent. Standard prediction methods are complicated by non-linearity and monitoring methods that are insufficiently responsive. A method for dynamically predicting the particle fallout in a cleanroom using air particle counter data was determined by numerical correlation. This method provides a simple linear correlation to both time and air quality, which can be monitored in real time. The summation of effects provides the program better understanding of the cleanliness and assists in the planning of future activities. Definition of fallout rates within a cleanroom during assembly and integration of contamination-sensitive hardware, such as the James Webb Space Telescope, is essential for budgeting purposes. Balancing the activity levels for assembly and test with the particle accumulation rate is paramount. The current approach to predicting particle fallout in a cleanroom assumes a constant air quality based on the rated class of a cleanroom, with adjustments for projected work or exposure times. Actual cleanroom class can also depend on the number of personnel present and the type of activities. A linear correlation of air quality and normalized particle fallout was determined numerically. An air particle counter (standard cleanroom equipment) can be used to monitor the air quality on a real-time basis and determine the "class" of the cleanroom (per FED-STD-209 or ISO-14644). The correlation function provides an area coverage coefficient per class-hour of exposure. The prediction of particle accumulations provides scheduling inputs for activity levels and cleanroom class requirements.

  18. Underground muon counters as a tool for composition analyses

    Science.gov (United States)

    Supanitsky, A. D.; Etchegoyen, A.; Medina-Tanco, G.; Allekotte, I.; Gómez Berisso, M.; Medina, M. C.

    2008-07-01

    The transition energy from galactic to extragalactic cosmic ray sources is still uncertain, but it should be associated either with the region of the spectrum known as the second knee or with the ankle. The baseline design of the Pierre Auger Observatory was optimized for the highest energies. The surface array is fully efficient above 3 × 10 18 eV and, even if the hybrid mode can extend this range below 10 18 eV, the second knee and a considerable portion of the wide ankle structure are left outside its operating range. Therefore, in order to encompass these spectral features and gain further insight into the cosmic ray composition variation along the transition region, enhancements to the surface and fluorescence components of the baseline design are being implemented that will lower the full efficiency regime of the Observatory down to ˜10 17 eV. The surface enhancements consist of a graded infilled area of standard Auger water Cherenkov detectors deployed in two triangular grids of 433 m and 750 m of spacing. Each surface station inside this area will have an associated muon counter detector. The fluorescence enhancement, on the other hand, consists of three additional fluorescence telescopes with higher elevation angle (30°-58°) than the ones in operation at present. The aim of this paper is threefold. We study the effect of the segmentation of the muon counters and find an analytical expression to correct for the under counting due to muon pile-up. We also present a detailed method to reconstruct the muon lateral distribution function for the 750 m spacing array. Finally, we study the mass discrimination potential of a new parameter, the number of muons at 600 m from the shower axis, obtained by fitting the muon data with the above mentioned reconstruction method.

  19. Development of High Pressure Xe Scintillation Proportional Counter for Experiments in "Low-Background" Physics

    OpenAIRE

    Akimov, D.Yu.; Burenkov, A. A; Churakov, D. L.; Kuzichev, V. F.; Morgunov, V. L.; Smirnov, G. N.; Solovov, V.N.

    1997-01-01

    Characteristics of a scintillation proportional counter with WLS fiber optics readout is described. The possibility of detection of the proportional scintillation signal produced by the single electron of primary ionization is shown. The counter can be applied for the experiments in "low--background" physics which require a low energy threshold.

  20. Counter narratives inplace and city branding and their influence on brand mangement

    DEFF Research Database (Denmark)

    Jørgensen, Ole Have

    2016-01-01

    The study is aimed at describing the types of counter narratives evolving in a city brand process, how they are understood and dealt with and how they may influence brand mangement.......The study is aimed at describing the types of counter narratives evolving in a city brand process, how they are understood and dealt with and how they may influence brand mangement....

  1. Analysis of Thermal Stability of Different Counter on 28nm FPGA

    DEFF Research Database (Denmark)

    Gupta, Daizy; Yadav, Amit; Hussain, Dil muhammed Akbar

    2016-01-01

    In this paper we are presenting the power analysis for thermal awareness of different counters. The technique we are using to do the analysis is based on 28 nm FPGA tech-nique. In this work during implementation on FPGA, we are going to analyze thermal stability of different counters in temperature...

  2. A BRIEF HISTORY OF COUNTER AND SUSHI: the evolution of interdependent standards

    National Research Council Canada - National Science Library

    Oliver Pesch

    2015-01-01

    ... and the supporting Standardized Usage Statistics Harvesting (SUSHI) standard. 2000 - 2003: COUNTER formed The timeline shows 2002 as the year the COUNTER initiative was launched, but the work that led up to this had begun in earnest a few years before. Under the auspices of the Publishers and Libraries Solutions (PALS1) group, librarians and publishers had been ...

  3. Gramscian ‘Counter hegemony’ in Narendra Modi’s New India Perspective

    Directory of Open Access Journals (Sweden)

    Venkat Rao Pulla

    2017-03-01

    Full Text Available The counter hegemony   that Gramsci, (1987:344 talks about is about leaders and their understanding and how well they conceptualise the psychology of the masses. Counter hegemonies have transformative power and Modi continues to prove that. In this special editorial, the author reviews the leadership of Mr Modi in India.

  4. Challenging Colorblindness in Arizona: Latina/o Students' Counter-Narratives of Race and Racism

    Science.gov (United States)

    Cammarota, Julio

    2014-01-01

    This essay reviews Latina/o students' counter-narratives challenging colorblindness. The author highlights the experiences of students from Tucson Unified School District's Mexican American Studies program. By examining student counter-narratives, the author also identifies race-related terms that are more suitable for dialogue among and with…

  5. Crisis and perspectives on policy change: Swedish counter-terrorism policymaking

    NARCIS (Netherlands)

    Hansén, D.H.

    2007-01-01

    Crisis experience are often said to be catalysts for policy change. A look back at the policy change initiatives in counter-terrorism policy post 9/11, 3/11 and 7/7, suggests a clear pattern. Crises generate policy change. However, prior to these attacks Swedish counter-terrorism policy change follo

  6. Fuzzy Reasoning Methods by Choosing Different Fuzzy Counters and Analysis of Effect

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Different fuzzy reasoning methods were gave by choosing different fuzzy counters. This article generally introduced the basic structure of fuzzy controller,and compared and analysised the reasoning effect of fuzzy reasoning methods and the effect of computer simulating control basicly on different fuzzy counters.

  7. A voltammetry study on the diffusion of counter ions in polypyrrole films

    DEFF Research Database (Denmark)

    Careem, M.A.; Velmurugu, Yogambigai; Skaarup, Steen;

    2006-01-01

    Polypyrrole (PPy) films doped with large immobile dodecyl benzene sulfonate (DBS) anions have been cycled in electrolytes of different concentration in an investigation of the diffusion of counter ions in this polymer complex. The diffusion of counter ions determines the speed of response of the ...

  8. Performance of microstrip proportional counters for x-ray astronomy on spectrum-roentgen-gamma

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Carl; BAHNSEN, A; Christensen, Finn Erland

    1991-01-01

    DSRI will provide a set of four imaging proportional counters for the Danish-Soviet X-ray telescopes XSPECT/SODART. The sensor principle is based on the novel micro-strip proportional counter (MSPC), where the strip electrodes are deposited by photolithography onto a rigid substrate. The MSPC off...

  9. Determination of dose rates in beta radiation fields using extrapolation chamber and GM counter

    DEFF Research Database (Denmark)

    Borg, J.; Christensen, P.

    1995-01-01

    of depth-dose profiles from different beta radiation fields with E(max) values down to 156 keV. Results are also presented from studies of GM counters for use as survey instruments for monitoring beta dose rates at the workplace. Advantages of GM counters are a simple measurement technique and high...

  10. Counter-Stereotypes and Images: An Exploratory Research and Some Questions

    Science.gov (United States)

    Morin-Messabel, Christine; Ferrière, Séverine; Martinez, Frederic; Devif, Julie; Reeb, Laurence

    2017-01-01

    The dynamics of the construction and perpetuation of gender stereotypes are classic research subjects in social psychology and in the field of educational guidelines in France. The most recent government decree aims to counter stereotypes in schools, by exposing pupils to counter-stereotypes. This study examines the effects of activating…

  11. Teacher Counter Stories to a Citizenship Education Mega Policy Narrative. Preparing for Citizenship in Chile

    Science.gov (United States)

    Cavieres-Fernández, Eduardo

    2017-01-01

    The present article focuses on the counter stories of two Chilean social studies high school teachers. Counter stories describe how teachers use their professional experience to confront those mega narratives composed of dominant educational policies that impinge upon their pedagogical practices. The mega narrative described in this study as a…

  12. Crisis and perspectives on policy change: Swedish counter-terrorism policymaking

    NARCIS (Netherlands)

    Hansén, D.H.

    2007-01-01

    Crisis experience are often said to be catalysts for policy change. A look back at the policy change initiatives in counter-terrorism policy post 9/11, 3/11 and 7/7, suggests a clear pattern. Crises generate policy change. However, prior to these attacks Swedish counter-terrorism policy change

  13. Multicultural Young Adult Literature as a Form of Counter-Storytelling

    Science.gov (United States)

    Hughes-Hassell, Sandra

    2013-01-01

    Counter-storytelling is defined by critical race theory scholars as a method of telling the stories of those people whose experiences are not often told, including people of color, the poor, and members of the LGBTQ community. This article discusses multicultural young adult literature as a form of counter-storytelling, with an emphasis on how…

  14. Analysis of Thermal Stability of Different Counter on 28nm FPGA

    DEFF Research Database (Denmark)

    Gupta, Daizy; Yadav, Amit; Hussain, Dil muhammed Akbar

    2016-01-01

    In this paper we are presenting the power analysis for thermal awareness of different counters. The technique we are using to do the analysis is based on 28 nm FPGA tech-nique. In this work during implementation on FPGA, we are going to analyze thermal stability of different counters in temperature...

  15. Is counter-terrorism policy evidence-based? What works, what harms, and what is unknown.

    Science.gov (United States)

    Lum, Cynthia; Kennedy, Leslie W; Sherley, Alison

    2008-02-01

    Is counter-terrorism policy evidence-based? What works, what harms, and what is unknown. One of the central concerns surrounding counter-terrorism interventions today, given the attention and money spent on them, is whether such interventions are effective. To explore this issue, we conducted a general review of terrorism literature as well as a Campbell systematic review on counter-terrorism strategies. In this article, we summarize some of our findings from these works. Overall, we found an almost complete absence of evaluation research on counter-terrorism strategies and conclude that counter-terrorism policy is not evidence-based. The findings of this review emphasise the need for government leaders, policy makers, researchers, and funding agencies to include and insist on evaluations of the effectiveness of these programs in their agendas.

  16. Alcohol counter-advertising and the media. A review of recent research.

    Science.gov (United States)

    Agostinelli, Gina; Grube, Joel W

    2002-01-01

    Counter-advertising commonly is used to balance the effects that alcohol advertising may have on alcohol consumption and alcohol-related problems. Such measures can take the form of print or broadcast advertisements (e.g., public service announcements [PSAs]) as well as product warning labels. The effectiveness of both types of counter-advertising is reviewed using the Elaboration Likelihood Model as a theoretical framework. For print and broadcast counter-advertisements, such factors as their emotional appeal and the credibility of the source, as well as audience factors, can influence their effectiveness. Further, brewer-sponsored counter-advertisements are evaluated and received differently than are the more conventional PSA counter-advertisements. For warning labels, both the content and design of the label influence their effectiveness, as do audience factors. The effectiveness of those labels is evaluated in terms of the extent to which they impact cognitive and affective processes as well as drinking behavior.

  17. Counter-Rotatable Fan Gas Turbine Engine with Axial Flow Positive Displacement Worm Gas Generator

    Science.gov (United States)

    Giffin, Rollin George (Inventor); Murrow, Kurt David (Inventor); Fakunle, Oladapo (Inventor)

    2014-01-01

    A counter-rotatable fan turbine engine includes a counter-rotatable fan section, a worm gas generator, and a low pressure turbine to power the counter-rotatable fan section. The low pressure turbine maybe counter-rotatable or have a single direction of rotation in which case it powers the counter-rotatable fan section through a gearbox. The gas generator has inner and outer bodies having offset inner and outer axes extending through first, second, and third sections of a core assembly. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes and extending radially outwardly and inwardly respectively. The helical blades have first, second, and third twist slopes in the first, second, and third sections respectively. A combustor section extends through at least a portion of the second section.

  18. The alignment and measurement of the magnetic field for muon counter at BESIII

    CERN Document Server

    Gao, Qing; Li, Chunhua

    2016-01-01

    Based on cosmic ray events taken without magnet filed during summer shutdown, we compare the coordinates of hits in muon counter with the expected interaction point of extrapolated tracks from the inner tracking system. By minimizing the difference, we align the muon counter with the inner tracking system. The muon counter is operating in magnetic return yoke and the magnetic field has never been measured before. The strength of the magnetic field of the muon counter is measured for the first time with $\\mu^+$ and $\\mu^-$ separately. After the alignment and magnetic field measurement, the offsets of hit-position for $\\mu^+$ and $\\mu^-$ are diminished. The alignment and magnetic field measurement are adopted in the latest BESIII offline software system. This makes physics analysis involving muon counter information more reliable.

  19. Shielding concepts for low-background proportional counter arrays in surface laboratories

    CERN Document Server

    Aalseth, Craig E; Mace, Emily K; Orrell, John L; Seifert, Allen; Williams, Richard M

    2015-01-01

    Development of ultra low background gas proportional counters has made the contribution from naturally occurring radioactive isotopes -- primarily $\\alpha$ and $\\beta$ activity in the uranium and thorium decay chains -- inconsequential to instrumental sensitivity levels when measurements are performed in above ground surface laboratories. Simple lead shielding is enough to mitigate against gamma rays as gas proportional counters are already relatively insensitive to naturally occurring gamma radiation. The dominant background in these surface laboratory measurements using ultra low background gas proportional counters is due to cosmic ray generated muons, neutrons, and protons. Studies of measurements with ultra low background gas proportional counters in surface and underground laboratories as well as radiation transport Monte Carlo simulations suggest a preferred conceptual design to achieve the highest possible sensitivity from an array of low background gas proportional counters when operated in a surface...

  20. Investigation of structure of superconducting power transmission cables with LN2 counter-flow cooling

    Science.gov (United States)

    Furuse, Mitsuho; Fuchino, Shuichiro; Higuchi, Noboru

    2003-04-01

    Establishment of long-distance cooling techniques and design of a compact cross section are required for development of HTC superconducting underground power cables. To save space of return coolant, a counter-flow cooling system appears promising. However, it is difficult to cool down long cables because of heat exchange between counter-flows due to high thermal conductivity of dielectric materials which separate both flows in range of liquid nitrogen temperature. We estimated temperature distributions analytically along model HTS power cables with counter-flow. Results of calculation showed that when liquid-nitrogen-impregnated polypropylene laminated paper was chosen for a dielectric material, great thickness was required to reduce heat exchange between counter-flows. We investigated various cable structures to optimize the counter-flow cooling system and cable size.

  1. The Performance and Long Term Stability of the D0 Run II Forward Muon Scintillation Counters

    Energy Technology Data Exchange (ETDEWEB)

    Bezzubov, V. [Serpukhov, IHEP; Denisov, D. [Fermilab; Evdokimov, V. [Serpukhov, IHEP; Lipaev, V. [Serpukhov, IHEP; Shchukin, A. [Serpukhov, IHEP; Vasilyev, I. [Serpukhov, IHEP

    2014-07-21

    The performance of the D0 experiment forward muon scintillation counters system during Run II of the Tevatron from 2001 to 2011 is described. The system consists of 4214 scintillation counters in six layers. The long term stability of the counters amplitude response determined using LED calibration system and muons produced in proton-antiproton collisions is presented. The average signal amplitude for counters of all layers has gradually decreased over ten years by 11%. The reference timing, determined using LED calibration, was stable within 0.26 ns. Average value of muon timing peak position was used for periodic D0 clock signal adjustments to compensate seasonal drift caused by temperature variations. Counters occupancy for different triggers in physics data collection runs and for minimum bias triggers are presented. The single muon yields versus time and the luminosity dependence of yields were stable for the forward muon system within 1% over 10 years.

  2. Interacting galaxies: corotating and counter-rotating systems with tidal tails

    Science.gov (United States)

    Mesa, Valeria; Duplancic, Fernanda; Alonso, Sol; Coldwell, Georgina; Lambas, Diego G.

    2014-02-01

    We analyse interacting galaxy pairs with evidence of tidal features in the Sloan Digital Sky Survey Data Release 7. The pairs were selected within z visual inspection pairs of spirals into corotating and counter-rotating systems. For a subsample of non-active galactic nucleus (non-AGN) galaxies, counter-rotating pairs have larger star formation rates and a higher fraction of young, star-forming galaxies. These effects are enhanced by restricting to rp Composite and Ambiguous AGN are similar. Also, counter-rotating hosts have more powerful AGN as revealed by enhanced Lum[O III] values. The number of corotating systems is approximately twice the number of counter-rotating pairs which could be owed to a more rapid evolution of counter-rotating systems, besides possible different initial conditions of these interacting pairs.

  3. Proportional counter for X-ray analysis of lunar and planetary surfaces. [a position sensitive scintillating imaging proportional counter

    Science.gov (United States)

    1979-01-01

    A position sensitive proportional scintillation detector was developed and evaluated for use in applications involving X-ray imaging as well as spectroscopy. Topics covered include limitations of the proportional scintillation counter for use in space; purification of the xenon gas in the detector, and the operation of the detector system. Results show that the light signal in a proportional scintillation detector remains well localized. With modest electric fields in xenon, the primary electrons from a photoelectric absorption of an X-ray can be brought a distance of a few millimeters to a higher field region without spreading more than a millimeter or so. Therefore, it is possible to make a proportional scintillation detector with good position sensitivity that could be used to calibrate out the difference in light collection over its sensitive volume.

  4. Rich Counter-Examples for Temporal-Epistemic Logic Model Checking

    Directory of Open Access Journals (Sweden)

    Simon Busard

    2012-02-01

    Full Text Available Model checking verifies that a model of a system satisfies a given property, and otherwise produces a counter-example explaining the violation. The verified properties are formally expressed in temporal logics. Some temporal logics, such as CTL, are branching: they allow to express facts about the whole computation tree of the model, rather than on each single linear computation. This branching aspect is even more critical when dealing with multi-modal logics, i.e. logics expressing facts about systems with several transition relations. A prominent example is CTLK, a logic that reasons about temporal and epistemic properties of multi-agent systems. In general, model checkers produce linear counter-examples for failed properties, composed of a single computation path of the model. But some branching properties are only poorly and partially explained by a linear counter-example. This paper proposes richer counter-example structures called tree-like annotated counter-examples (TLACEs, for properties in Action-Restricted CTL (ARCTL, an extension of CTL quantifying paths restricted in terms of actions labeling transitions of the model. These counter-examples have a branching structure that supports more complete description of property violations. Elements of these counter-examples are annotated with parts of the property to give a better understanding of their structure. Visualization and browsing of these richer counter-examples become a critical issue, as the number of branches and states can grow exponentially for deeply-nested properties. This paper formally defines the structure of TLACEs, characterizes adequate counter-examples w.r.t. models and failed properties, and gives a generation algorithm for ARCTL properties. It also illustrates the approach with examples in CTLK, using a reduction of CTLK to ARCTL. The proposed approach has been implemented, first by extending the NuSMV model checker to generate and export branching counter

  5. Training Post-9/11 Police Officers with a Counter-Terrorism Reality-Based Training Model: A Case Study

    Science.gov (United States)

    Biddle, Christopher J.

    2013-01-01

    The purpose of this qualitative holistic multiple-case study was to identify the optimal theoretical approach for a Counter-Terrorism Reality-Based Training (CTRBT) model to train post-9/11 police officers to perform effectively in their counter-terrorism assignments. Post-9/11 police officers assigned to counter-terrorism duties are not trained…

  6. Training Post-9/11 Police Officers with a Counter-Terrorism Reality-Based Training Model: A Case Study

    Science.gov (United States)

    Biddle, Christopher J.

    2013-01-01

    The purpose of this qualitative holistic multiple-case study was to identify the optimal theoretical approach for a Counter-Terrorism Reality-Based Training (CTRBT) model to train post-9/11 police officers to perform effectively in their counter-terrorism assignments. Post-9/11 police officers assigned to counter-terrorism duties are not trained…

  7. Transparent platinum counter electrode for efficient semi-transparent dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Iefanova, Anastasiia; Nepal, Jeevan; Poudel, Prashant; Davoux, Daren; Gautam, Umesh [Electrical Engineering and Computer Science Department, South Dakota State University, Brookings, SD 57006 (United States); Mallam, Venkataiah [Chemistry and Biochemistry Department, South Dakota State University, Brookings, SD 57006 (United States); Qiao, Qiquan [Electrical Engineering and Computer Science Department, South Dakota State University, Brookings, SD 57006 (United States); Logue, Brian [Chemistry and Biochemistry Department, South Dakota State University, Brookings, SD 57006 (United States); Baroughi, Mahdi Farrokh, E-mail: m.farrokhbaroughi@sdstate.edu [Electrical Engineering and Computer Science Department, South Dakota State University, Brookings, SD 57006 (United States)

    2014-07-01

    A method for fabrication of highly transparent platinum counter electrodes (CEs) has been developed based on spray coating of Pt nanoparticles (NPs) on hot substrates. This method leads to 86% reduction in Pt consumption reducing the Pt cost per peak watt of counter electrode from $0.79/Wp down to $0.11/Wp compared to the conventional Pt counter electrodes made by sputter deposition. The simplicity and low cost of this method provide a basis for an up-scalable fabrication process. The Pt NP layer is over 88% transparent, leading to overall transparency of 80% when incorporated with indium tin oxide/glass substrates for functional counter electrodes. This counter electrode exhibits a large surface area and high catalytic activity, comparable to that of the conventional opaque CEs. Semi-transparent dye-sensitized solar cells fabricated based on this counter electrode showed 6.17% power conversion efficiency. - Highlights: • Counter electrode (CE) prepared by spraying nanoparticle (NP) Pt on hot substrate. • Low cost and scalable fabrication process of CE. • The spray deposited CE uses 10 times less Pt compared to the sputtering method. • The CE is 80% transparent and exhibits a large surface and high catalytic activity. • A semitransparent dye-sensitized solar cell with Pt NP CE was 6.17% efficient.

  8. THE COUNTER-JET FORMATION IN AN AIR BUBBLE INDUCED BY THE IMPACT OF SHOCK WAVES

    Institute of Scientific and Technical Information of China (English)

    BAI Li-xin; XU Wei-lin; LI Chao; GAO Yan-dong

    2011-01-01

    The interaction of an air bubble (isolated in water or attached to a boundary) with shock waves induced by electric sparks is investigated by high-speed photography.The interaction is closely related to the counter-jet induced by the impact of shock waves.The formation of a counter-jet in an air bubble is related to the liquid jet formed in the same air bubble,but the mechanism is different with that of the counter-jet formation in a collapsing cavitation bubble.The formation of a counter-jet in an air bubble is related to discharge energy,air bubble size and radius of shock wave.With a given energy of the spark discharge,the formation of a counter-jet in an air bubble is related to δ/ε (the ratio of the dimensionless bubble-bubble distance to the dimensionless air bubble radius).The counter-jet will only be produced when δ/ε is in the range of 1.2-2.2.The counter-jet in an air bubble is of an important nuclei-generating mechanism.

  9. Design of a hybrid gas proportional counter with CdTe guard counters for sup 1 sup 4 C dating system

    CERN Document Server

    Zhang, L; Hinamoto, N; Nakazawa, M; Yoshida, K

    2002-01-01

    Nowadays uniform, low-cost and large-size compound semiconductor detectors are available up to several square centimeters. We are trying to combine this technology with conventional gas detectors to upgrade an anticoincidence type proportional counter, Oeschger-type thin wall counter of 2.2 l, used for a sup 1 sup 4 C dating facility at the University of Tokyo. In order to increase the ratio of the signal to the background for smaller quantity of samples less than 1 g, an effective approach is to minimize the detector volume at higher gas pressure. However, the anticoincidence function suffers from such a small volume. Therefore we designed a new active wall gas counter of 0.13 l counting volume using CdTe compound semiconductor detectors as the wall of the gas proportional counter to perform anticoincidence. Simulation study showed that at noise thresholds less than 70 keV, the wall counters can reject above 99.8% of events arising from outer gamma rays. Measured noise levels of CdTe detectors were smaller t...

  10. MCNP modelling of a combined neutron/gamma counter

    CERN Document Server

    Bourva, L C A; Ottmar, H; Weaver, D R

    1999-01-01

    A series of Monte Carlo neutron calculations for a combined gamma/passive neutron coincidence counter has been performed. This type of device, part of a suite of non-destructive assay instruments utilised for the enforcement of the Euratom nuclear safeguards within the European Union, is to be used for high accuracy measurements of the plutonium content of small samples of nuclear materials. The multi-purpose Monte Carlo N-particle (MCNP) code version 4B has been used to model in detail the neutron coincidence detector and to investigate the leakage self-multiplication of PuO sub 2 and mixed U-Pu oxide (MOX) reference samples used to calibrate the instrument. The MCNP calculations have been used together with a neutron coincidence counting interpretative model to determine characteristic parameters of the detector. A comparative study to both experimental and previous numerical results has been performed. Sensitivity curves of the variation of the detector's efficiency, epsilon, to, alpha, the ratio of (alpha...

  11. Computer Crimes and Counter Measures in the Nigerian Banking Sector

    Directory of Open Access Journals (Sweden)

    Olasanmi, Omoneye Olufunke

    2010-04-01

    Full Text Available The increase in the use of the information and communication technology (ICT facilities such as computers and the Internet in the perpetration of criminal activities like spamming, credit card frauds, ATM fra uds, phishing, identity theft, denial - of - service, and a host of others has lend credence to the view that ICT is contributing to crime in the banking sector. A greater understanding of such computer crimes may complement existing security practices by poss ibly highlighting new areas of counter measures. This paper thus assesses whether these crimes can be totally eradicated or not and whether the new generation banks experience more computer crimes than the old generation banks in Nigeria. Based on the find ings of this study, the paper concludes that total eradication of computer crimes is not possible but can be highly reduced if internal control measures are adequately put in place within a bank’s organizational structure and that new generation banks seem to experience more crimes than their old generation counterparts due to the fact that majority of their services, which are automated, are subjected to technological changes at a rapid rate

  12. LiF/ZnS neutron multiplicity counter

    Energy Technology Data Exchange (ETDEWEB)

    Stave, Sean, E-mail: sean.stave@pnnl.gov; Bliss, Mary; Kouzes, Richard; Lintereur, Azaree; Robinson, Sean; Siciliano, Edward; Wood, Lynn

    2015-06-01

    The availability of {sup 3}He in recent years is becoming restricted with an order of magnitude price increase for this material. Alternatives to the use of {sup 3}He for the detection of thermal neutrons are under investigation. One of the most challenging applications for {sup 3}He alternatives is in neutron multiplicity counters that provide rapid assay of samples which contain an unknown amount of plutonium in a potentially unknown configuration. With appropriate detector design that has minimal gamma-ray sensitivity and a high detection efficiency even for triple coincidence events, the neutron single, double, and triple coincidence events can be used to extract three unknown parameters such as the {sup 240}Pu-effective mass, the sample self-multiplication, and the (α,n) rate. This project is aimed at determining if commercially available {sup 3}He alternatives can satisfy this challenging application. Using MCNP modeling the best alternative identified used LiF/ZnS neutron-scintillator sheets and wavelength shifting plastic for light pipes. A four-panel demonstrator module has been constructed, tested, and compared with detailed modeling results. However, to attain that desired high-level of performance two primary design challenges must be addressed. They include building a fast electronics system and robust neutron/gamma-ray discrimination based on pulse shape analysis at high rates. A review of the current effort and the most recent findings will be presented.

  13. Particle Identification Using a Ring Imaging Cherenkov Counter

    Science.gov (United States)

    Goodwill, Justin; Benmokthar, Fatiha

    2016-09-01

    The installation of a Ring Imaging Cherenkov counter (RICH) on the CLAS12 spectrometer in Hall B of Jefferson Lab will aid in particle identification, specifically with regard to the separation between protons, pions, kaons. The RICH functions by detecting a ring of radiation that is given off by particles moving faster than the speed of light in a medium through the use of multi-anode photomultiplier tubes (MAPMTs). Because the size of the ring is dependent on the velocity of the particles, one can separate the incoming charged particles. With 391 MAPMTs being used in the specific design at Jefferson Lab, sophisticated electronic systems are needed to achieve complete data acquisition and ensure the safe operation of RICH. To monitor these electronic systems, the slow control system uses a compilation of graphical user interfaces (GUIs) that communicates and, if necessary, changes certain process variables such as the high voltage going to the MAPMTs and the temperature of the system. My actual project focuses on the development of an efficient and reliable slow control system for this detector as well as a java based analyzer for offline data analysis.

  14. Counter-streaming radiative shock experiments on the Orion laser

    Science.gov (United States)

    Suzuki-Vidal, F.; Clayson, T.; Swadling, G. F.; Patankar, S.; Burdiak, G. C.; Lebedev, S. V.; Smith, R. A.; Stehle, C.; Chaulagain, U.; Singh, R. L.; Larour, J.; Kozlova, M.; Spindloe, C.; Foster, J.; Skidmore, J.; Gumbrell, E.; Graham, P.; Danson, C.

    2016-10-01

    The formation of radiative shocks, shocks in which the structure of density and temperature is affected by radiation from the shock-heated matter, is ubiquitous in many astrophysical scenarios. Experiments were performed at the Orion laser using a new target configuration that allows studying the formation of single and counter-streaming radiative shocks in gas-filled targets (Ne, Ar, Kr, Xe), with initial pressures 0.1-1 bar and a driver intensity of 6x1014 W/cm2 . The shocks propagate at velocities >60 km/s and were diagnosed with optical interferometry (streaked and time-resolved) and point-projection X-ray backlighting allowing to probe simultaneously the pre-shock radiative precursor and the shock front itself. Besides varying the extent of the radiative precursor the results show that different gases seem to have an effect on the shock front as evidenced by a number of spatial features. The results are compared with radiative hydrodynamics simulations in 1-D (HELIOS) and 2-D (NYM/PETRA). Supported by Orion Academic Access, the Royal Society, EPSRC, Labex PLAS@PAR. Currently at (2) LLNL, USA, (3) ELI, CZ, (4) First Light Fusion, UK.

  15. Ring Counter Based ATPG for Low Transition Test Pattern Generation.

    Science.gov (United States)

    Begam, V M Thoulath; Baulkani, S

    2015-01-01

    In test mode test patterns are applied in random fashion to the circuit under circuit. This increases switching transition between the consecutive test patterns and thereby increases dynamic power dissipation. The proposed ring counter based ATPG reduces vertical switching transitions by inserting test vectors only between the less correlative test patterns. This paper presents the RC-ATPG with an external circuit. The external circuit consists of XOR gates, full adders, and multiplexers. First the total number of transitions between the consecutive test patterns is determined. If it is more, then the external circuit generates and inserts test vectors in between the two test patterns. Test vector insertion increases the correlation between the test patterns and reduces dynamic power dissipation. The results prove that the test patterns generated by the proposed ATPG have fewer transitions than the conventional ATPG. Experimental results based on ISCAS'85 and ISCAS'89 benchmark circuits show 38.5% reduction in the average power and 50% reduction in the peak power attained during testing with a small size decoding logic.

  16. Countering Climate Confusion in the Classroom: New Methods and Initiatives

    Science.gov (United States)

    McCaffrey, M.; Berbeco, M.; Reid, A. H.

    2014-12-01

    Politicians and ideologues blocking climate education through legislative manipulation. Free marketeers promoting the teaching of doubt and controversy to head off regulation. Education standards and curricula that skim over, omit, or misrepresent the causes, effects, risks and possible responses to climate change. Teachers who unknowingly foster confusion by presenting "both sides" of a phony scientific controversy. All of these contribute to dramatic differences in the quality and quantity of climate education received by U.S. students. Most U.S. adults and teens fail basic quizzes on energy and climate basics, in large part, because climate science has never been fully accepted as a vital component of a 21st-century science education. Often skipped or skimmed over, human contributions to climate change are sometimes taught as controversy or through debate, perpetuating a climate of confusion in many classrooms. This paper will review recent history of opposition to climate science education, and explore initial findings from a new survey of science teachers on whether, where and how climate change is being taught. It will highlight emerging effective pedagogical practices identified in McCaffrey's Climate Smart & Energy Wise, including the role of new initiatives such as the Next Generation Science Standards and Green Schools, and detail efforts of the Science League of America in countering denial and doubt so that educators can teach consistently and confidently about climate change.

  17. Encapsulation of liquids using a counter rotating twin screw extruder.

    Science.gov (United States)

    Tackenberg, Markus W; Krauss, Ralph; Marmann, Andreas; Thommes, Markus; Schuchmann, Heike P; Kleinebudde, Peter

    2015-01-01

    Until now extrusion is not applied for pharmaceutical encapsulation processes, whereas extrusion is widely used for encapsulation of flavours within food applications. Based on previous mixing studies, a hot melt counter-rotating extrusion process for encapsulation of liquid active pharmaceutical ingredients (APIs) was investigated. The mixing ratio of maltodextrin to sucrose as matrix material was adapted in first extrusion trials. Then the number of die holes was investigated to decrease expansion and agglutination of extrudates to a minimum. At a screw speed of 180 min(-1) the product temperature was decreased below 142 °C, resulting in extrudates of cylindrical shape with a crystalline content of 9-16%. Volatile orange terpenes and the nonvolatile α-tocopherol were chosen as model APIs. Design of experiments were performed to investigate the influences of barrel temperature, powder feed rate, and API content on the API retentions. A maximum of 9.2% α-tocopherol was encapsulated, while the orange terpene encapsulation rate decreased to 6.0% due to evaporation after leaving the die. During 12 weeks of storage re-crystallization of sucrose occurred; however, the encapsulated orange terpene amount remained unchanged.

  18. Applying Stylometric Analysis Techniques to Counter Anonymity in Cyberspace

    Directory of Open Access Journals (Sweden)

    Jianwen Sun

    2012-02-01

    Full Text Available Due to the ubiquitous nature and anonymity abuses in cyberspace, it’s difficult to make criminal identity tracing in cybercrime investigation. Writeprint identification offers a valuable tool to counter anonymity by applying stylometric analysis technique to help identify individuals based on textual traces. In this study, a framework for online writeprint identification is proposed. Variable length character n-gram is used to represent the author’s writing style. The technique of IG seeded GA based feature selection for Ensemble (IGAE is also developed to build an identification model based on individual author level features. Several specific components for dealing with the individual feature set are integrated to improve the performance. The proposed feature and technique are evaluated on a real world data set encompassing reviews posted by 50 Amazon customers. The experimental results show the effectiveness of the proposed framework, with accuracy over 94% for 20 authors and over 80% for 50 ones. Compared with the baseline technique (Support Vector Machine, a higher performance is achieved by using IGAE, resulting in a 2% and 8% improvement over SVM for 20 and 50 authors respectively. Moreover, it has been shown that IGAE is more scalable in terms of the number of authors, than author group level based methods.

  19. Enhanced eyelashes: prescription and over-the-counter options.

    Science.gov (United States)

    Jones, Derek

    2011-02-01

    Women have long strived to possess long, thick, and dark eyelashes. Prominent eyes and eyelashes are often considered a sign of beauty and can be associated with increased levels of attractiveness, confidence, and well-being. Numerous options may improve the appearance of eyelashes. Mascara aims to temporarily darken, lengthen, and thicken eyelashes using a combination of waxes, pigments, and resins. Artificial eyelashes can be adhered either to the dermal margin or to individual eyelashes. Individuals may even use eyelash transplantations to improve the appearance of their eyelashes. The unique properties of eyelashes (e.g., relatively long telogen and short anagen phases compared with scalp hairs, slow rate of growth, and a lack of influence by androgens) may allow for specific aesthetic interventions to improve the appearance of natural eyelashes. Some over-the-counter (OTC) products may contain prostaglandin analogs that can affect eyelash growth, but neither the safety nor efficacy of these OTC cosmetics has been fully studied. Originally indicated for the reduction of intraocular pressure, the synthetic prostaglandin analog bimatoprost was recently approved for the treatment of hypotrichosis of the eyelashes. In a double-blinded, randomized, vehicle-controlled trial, bimatoprost safely and effectively grew natural eyelashes, making them longer, thicker, and darker. Bimatoprost was generally safe and well tolerated and appears to provide an additional option for individuals looking to improve the appearance of their eyelashes.

  20. The Role of Hackers in Countering Surveillance and Promoting Democracy

    Directory of Open Access Journals (Sweden)

    Sebastian Kubitschko

    2015-09-01

    Full Text Available Practices related to media technologies and infrastructures (MTI are an increasingly important part of democratic constellations in general and of surveillance tactics in particular. This article does not seek to discuss surveillance per se, but instead to open a new line of inquiry by presenting qualitative research on the Chaos Computer Club (CCC—one of the world’s largest and Europe’s oldest hacker organizations. Despite the longstanding conception of hacking as infused with political significance, the scope and style of hackers’ engagement with emerging issues related to surveillance remains poorly understood. The rationale of this paper is to examine the CCC as a civil society organization that counter-acts contemporary assemblages of surveillance in two ways: first, by de-constructing existing technology and by supporting, building, maintaining and using alternative media technologies and infrastructures that enable more secure and anonymous communication; and second, by articulating their expertise related to contemporary MTI to a wide range of audiences, publics and actors. Highlighting the significance of “privacy” for the health of democracy, I argue that the hacker organization is co-determining “interstitial spaces within information processing practices” (Cohen, 2012, p. 1931, and by doing so is acting on indispensable structural features of contemporary democratic constellations.

  1. [Factors related to purchasing over-the-counter medications online].

    Science.gov (United States)

    Kishimoto, Keiko; Yoshida, Takeshi; Fukushima, Noriko

    2009-09-01

    We conducted a Web-based survey of approximately 40,000 Internet users on the purchase of over-the-counter (OTC) medications online in March 2009. The valid response rate was 97.8% and the number of responses was 39,208. The number of people who had purchased OTC medications online was 4,653 (11.9%), prescription medicines 792 (2.0%), and medical contact lenses 1,993 (5.1%). As a result of the multiple logistic regression analysis, independent variables with odds ratios (ORs) >1.5 were experience of purchasing prescription-only medicine online (OR=4.997, 95%CI=4.288-5.824), regular supplement use (OR=2.384, 95%CI=2.233-2.548), experience of purchasing colored contact lenses online (OR=2.206, 95%CI=1.632-2.983), no time to visit drugstores (OR=2.092, 95%CI=1.928-2.270), usage of Web sites of uncertain reliability (OR=1.992, 95%CI=1.857-2.137), and experience of purchasing therapeutic contact lenses online (OR=1.796, 95%CI=1.597-2.020). As some people have purchased prescription-only medicine or medical devices and had problems with drug information sources, the development of awareness of medical and pharmaceutical supplies and health and medical information literacy are key priorities to ensure safe OTC medication sales systems.

  2. Large-area proportional counter for in situ transuranic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Miller, K.M.

    1994-12-31

    Improved methods for site characterization are desired for environmental restoration at nuclear facilities. Measurements of transuranics, in particular several isotopes of plutonium, are especially difficult due to the low penetrating nature of the radiations involved, namely, alpha particles and X rays. The effects of attenuation by soil and vegetation generally render direct alpha survey methods useless. For this reason, thin scintillators, such as the FIDLER (field instrument for detection of low-energy radiation) or its more sophisticated successor, the VIOLINIST, that rely on the detection of the L shell X rays (13 to 21 keV) are used for survey work. Semiconductor detectors (germanium and silicon), used singly or in arrays, can be effective, especially for situations where {sup 241}Am (60 keV) is present in the isotropic mix. In principle, in situ spectrometric techniques that have been successfully applied at higher photon energies for the measurement of gamma-emitting radionuclides in the environment can be extended to the X-ray region as well. For situations where {sup 241}Am is not present or its ratio to plutonium is unknown, an alternative detector that we have explored for in situ X-ray spectrometry is a large-area proportional counter (LAPC). These instruments were developed for X-ray astronomical measurements in space and offer the combination of large window area and medium energy resolution. Smaller versions have also been used for lung counting.

  3. The Role of Hackers in Countering Surveillance and Promoting Democracy

    Directory of Open Access Journals (Sweden)

    Sebastian Kubitschko

    2015-09-01

    Full Text Available Practices related to media technologies and infrastructures (MTI are an increasingly important part of democratic constellations in general and of surveillance tactics in particular. This article does not seek to discuss surveillance per se, but instead to open a new line of inquiry by presenting qualitative research on the Chaos Computer Club (CCC—one of the world’s largest and Europe’s oldest hacker organizations. Despite the longstanding conception of hacking as infused with political significance, the scope and style of hackers’ engagement with emerging issues related to surveillance remains poorly understood. The rationale of this paper is to examine the CCC as a civil society organization that counter-acts contemporary assemblages of surveillance in two ways: first, by de-constructing existing technology and by supporting, building, maintaining and using alternative media technologies and infrastructures that enable more secure and anonymous communication; and second, by articulating their expertise related to contemporary MTI to a wide range of audiences, publics and actors. Highlighting the significance of “privacy” for the health of democracy, I argue that the hacker organization is co-determining “interstitial spaces within information processing practices” (Cohen, 2012, p. 1931, and by doing so is acting on indispensable structural features of contemporary democratic constellations.

  4. Light interference detection on-chip by integrated SNSPD counters

    Directory of Open Access Journals (Sweden)

    Paul Cavalier

    2011-12-01

    Full Text Available A SWIFTS device (Stationary Wave Integrated Fourier Transform Spectrometer has been realized with an array of 24 Superconducting Nanowire Single Photon Detectors (SNSPD, on-chip integrated under a Si3N4 monomode rib-waveguide interferometer. Colored light around 1.55μm wavelength is introduced through end-fire coupling, producing a counter-propagative stationary interferogram over the 40nm wide, 120nm spaced, 4nm thick epi-NbN nanowire array. Modulations in the source bandwidth have been detected using individual waveguide coupled SNSPDs operating in single photon counting mode, which is a step towards light spectrum reconstruction by inverse Fourier transform of the stationary wave intensity. We report the design, fabrication process and in-situ measurement at 4.2K of light power modulation in the interferometer, obtained with variable laser wavelength. Such micro-SWIFTS configuration with 160nm sampling period over 3.84μm distance allows a spectral bandwidth of 2μm and a wavelength resolution of 170nm. The light interferences direct sampling ability is unique and raises wide interest with several potential applications like fringe-tracking, metrology, cryptography or optical tomography.

  5. Technological Innovations to Counter CBRNE Threat Vectors and Ecotage

    Science.gov (United States)

    Vaseashta, Ashok

    The ubiquitous presence of sensors for enhanced situational awareness necessitates an innovative, articulate, and focused review of their design, architecture, functionality, and interoperability. A comprehensive overview of the latest and state-of-the art technological innovations in point and stand-off sensing/detection platforms with the objective of countering threats arising from chemical-biological-nuclear-high yield explosives (CBRNE) is the focus of this investigation. Ongoing research efforts and future research directions based on advanced approaches, including nanomaterials to develop materials, devices, and systems for potential use in sensing and detection of such threat vectors are articulated. The concept of advanced sciences convergences is introduced to examine the feasibility of potentially new and innovative research directions for persistent surveillance of CBRNE agents and infectious diseases. The intentional release of such agents in the environment constitutes ecological sabotage. Advanced sensing/detection platforms for CBRNE are used to detect threats to the environment. Issues associated with the use of nanomaterials regarding societal implications and dual-use concerns are addressed by studying fate and transport and the development of guidelines for a risk-assessment model. A roadmap of the future of nanomaterials, in terms of complexity, a nexus of disciplines, and its emerging potential to provide advanced, futuristic, and a paradigm-shifting platform is presented.

  6. Modelling counter-current chromatography: a chemical engineering perspective.

    Science.gov (United States)

    Kostanian, A E

    2002-10-11

    In conventional chromatography, a solute is usually viewed to be longitudinally transported only in the mobile phase, remaining longitudinally motionless in the stationary phase. In counter-current chromatography, both phases undergo intense mixing in the variable force field of a coil planet centrifuge and longitudinal dispersion of matter in the stationary phase is not to be excluded. To take into account longitudinal mixing in both phases, a cell model of chromatographic process is proposed in which the number of perfectly mixed cells n is determined by the rates of mixing in stationary (Ds) and mobile (Dm) phases by the equation n = LF/(2ADc)/(1 + Sf(lambda - 1)) with A = K(D)D(S)/Dm (F, L, Ac and KD are the mobile phase flow-rate, column length, column cross-section and distribution ratio, respectively). This equation has been derived by comparing the discontinuous cell model with continuous diffusion assuming equilibrium conditions. Parameter determination and their relationships are discussed.

  7. Low energy recoil detection with a spherical proportional counter

    CERN Document Server

    Savvidis, I; Eleftheriadis, C; Giomataris, I; Papaevangellou, T

    2016-01-01

    We present low energy recoil detection results in the keV energy region, from measurements performed with the Spherical Proportional Counter (SPC). An ${}^{241}Am-{}^{9}{Be}$ fast neutron source is used in order to obtain neutron-nucleus elastic scattering events inside the gaseous volume of the detector. The detector performance in the $keV$ energy region was resolved by observing the $5.9\\ keV$ line of a ${}^{55}Fe$ X-ray source, with energy resolution of $9\\%$ ($\\sigma$). The toolkit GEANT4 was used to simulate the irradiation of the detector by an ${}^{241}Am-{}^{9}{Be}$ source, while SRIM was used to calculate the Ionization Quenching Factor (IQF). The GEANT4 simulated energy deposition spectrum in addition with the SRIM calculated quenching factor provide valuable insight to the experimental results. The performance of the SPC in low energy recoil detection makes the detector a good candidate for a wide range of applications, including Supernova or reactor neutrino detection and Dark Matter (WIMP) searc...

  8. Robotic Billiards: Understanding Humans in Order to Counter Them.

    Science.gov (United States)

    Nierhoff, Thomas; Leibrandt, Konrad; Lorenz, Tamara; Hirche, Sandra

    2016-08-01

    Ongoing technological advances in the areas of computation, sensing, and mechatronics enable robotic-based systems to interact with humans in the real world. To succeed against a human in a competitive scenario, a robot must anticipate the human behavior and include it in its own planning framework. Then it can predict the next human move and counter it accordingly, thus not only achieving overall better performance but also systematically exploiting the opponent's weak spots. Pool is used as a representative scenario to derive a model-based planning and control framework where not only the physics of the environment but also a model of the opponent is considered. By representing the game of pool as a Markov decision process and incorporating a model of the human decision-making based on studies, an optimized policy is derived. This enables the robot to include the opponent's typical game style into its tactical considerations when planning a stroke. The results are validated in simulations and real-life experiments with an anthropomorphic robot playing pool against a human.

  9. Neutron spectroscopy with the Spherical Proportional Counter based on nitrogen gas

    Science.gov (United States)

    Bougamont, E.; Dastgheibi, A.; Derre, J.; Galan, J.; Gerbier, G.; Giomataris, I.; Gros, M.; Katsioulas, I.; Jourde, D.; Magnier, P.; Navick, X. F.; Papaevangelou, T.; Savvidis, I.; Tsiledakis, G.

    2017-03-01

    A novel large volume spherical proportional counter, recently developed, is used for neutron measurements. The pure N2 gas is studied for thermal and fast neutron detection, providing a new way for neutron spectroscopy. The neutrons are detected via the 14N (n , p)C14 and 14N (n , α)B11 reactions. The detector is tested for thermal and fast neutrons detection with 252Cf and 241Am -9Be neutron sources. The atmospheric neutrons are successfully measured from thermal up to several MeV, well separated from the cosmic ray background. A comparison of the spherical proportional counter with the current available neutron counters is also presented.

  10. Studies of timing properties for a TOF counter at an external target facility

    Institute of Scientific and Technical Information of China (English)

    YU Yu-Hong; XU Hua-Gen; XU Hu-Shan; ZHAN Wen-Long; SUN Zhi-Yu; GUO Zhong-Yan; HU Zheng-Guo; CHEN Jun-Ling; TANG Shu-Wen

    2009-01-01

    Timing and amplitude properties of a prototype scintillator TOF counter at an external target facility are studied with a cosmic rays test. The dependence of signal pulse height and time resolution on the coordinate along the scintillator TOF counter is investigated with two different discriminators. A time resolution of 165 ps can be achieved at the center of the counter with a constant fraction discriminator. Time resolution better than 150 ps is obtained at the center with a leading edge discriminator after time walk correction is applied for off-line analysis.

  11. Transient processes in the parametric interaction of counter-propagating waves

    Energy Technology Data Exchange (ETDEWEB)

    Slabko, V V; Rasskazova, E V; Tkachenko, V A; Moskalev, A K [Siberian Federal University, Krasnoyarsk (Russian Federation); Popov, A K [Purdue University, 1205 W State St, West Lafayette, IN 47907 (United States); Myslivets, S A [L.V.Kirensky Institute of Physics, Siberian Branch of the Russian Academy of Sciences, Academgorodok, Krasnoyarsk (Russian Federation)

    2015-12-31

    We present a comparative analysis of transient processes in media with a negative refractive index for the parametric interaction of co- and counter-propagating waves. The transient time for the interaction of counter-propagating waves is shown to considerably exceed that for the interaction of co-propagating waves. In the case of counter-propagating waves, we present fitting results for the generated wave amplitude as a function of time and for the transient time vs. the amplitude of the pump wave and the length of the medium. (optical metamaterials)

  12. Simulation of fuzzy control systems for nonferrous alloy vacuum counter-pressure casting

    Institute of Scientific and Technical Information of China (English)

    YAN Qing-song; CAI Qi-zhou; WEI Bo-kang; YU Huan; YU Zi-rong

    2005-01-01

    Through simulation analyses of vacuum counter-pressure casting fuzzy control systems based on MATLAB, fuzzy control systems designed by simulation can track technical route established well. When transmission functions of vacuum counter-pressure casting controlled objects are changed in operation, fuzzy control systems can carry on self-regulation and stabilize quickly, and embody the advantages of fleet response velocity and little adjusting quantity. The design of vacuum counter-pressure casting fuzzy control systems is accelerated and improved greatly by simulation based on MATLAB. Meanwhile, their design is accurate and reliable. Moreover, microstructure and properties of thin-wall aluminum alloy castings are improved effectively by using fuzzy control systems.

  13. Calibration constant of a silver activation counter used with plasma focus devices

    Directory of Open Access Journals (Sweden)

    GR Etaati

    2010-03-01

    Full Text Available The silver activation counters are commonly used for pulsed-neutron yield measurements especially in plasma focus devices. The counter normally consists of a Geiger-Muller tube along with silver foils and polyethylene (as a moderator, which is calibrated against an Am-Be radioisotope neutron source. The neutrons, after being slowed-down in the polyethylene, activate the silver foils. By measuring the foil activity with a Geiger-Muller counter, the neutron yield is determined. In the present paper, the activation counter’s calibration constant calculation using the MCNP4C code is explained. The calculated calibration constant is in good agreement with the experimental results.

  14. Counter-Democratic Surveillance: The Watchful Eye of a Local Institution

    DEFF Research Database (Denmark)

    Hjelholt, Morten

    2014-01-01

    ). The watchful eyes of counter-democratic organizations are particularly made powerful by the rise of the Internet with its spontaneous adaption of watchful functions. However increased awareness and mistrust have led not to broader participation in traditional liberal institutions but to a greater social...... attention and demand for transparency of information. This paper takes a closer look at dynamics of counter-democratic surveillance from the perspective of a local political institution. The paper reports on a 3-year research project on counter-democratic functions of institutional oversight and organised...

  15. Thomson scattering measurement of a shock in laser-produced counter-streaming plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Morita, T.; Kuramitsu, Y.; Moritaka, T. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Sakawa, Y.; Takabe, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Graduate School of Science, Osaka University, 1-1 Machikane-yama, Toyonaka, Osaka 560-0043 (Japan); Tomita, K.; Nakayama, K.; Inoue, K.; Uchino, K. [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1, Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Ide, T.; Tsubouchi, K. [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Nishio, K.; Ide, H.; Kuwada, M. [Graduate School of Science, Osaka University, 1-1 Machikane-yama, Toyonaka, Osaka 560-0043 (Japan)

    2013-09-15

    We report the first direct measurement of temporally and spatially resolved plasma temperatures at a shock as well as its spatial structure and propagation in laser-produced counter-streaming plasmas. Two shocks are formed in counter-streaming collisionless plasmas early in time, and they propagate opposite directions. This indicates the existence of counter-streaming collisionless flows to keep exciting the shocks, even though the collisional effects increase later in time. The shock images are observed with optical diagnostics, and the upstream and downstream plasma parameters of one of the shocks are measured using Thomson scattering technique.

  16. Hardware enabled performance counters with support for operating system context switching

    Science.gov (United States)

    Salapura, Valentina; Wisniewski, Robert W.

    2015-06-30

    A device for supporting hardware enabled performance counters with support for context switching include a plurality of performance counters operable to collect information associated with one or more computer system related activities, a first register operable to store a memory address, a second register operable to store a mode indication, and a state machine operable to read the second register and cause the plurality of performance counters to copy the information to memory area indicated by the memory address based on the mode indication.

  17. TOF-counter calibration for spectroscopy experiment of pionic atoms at RIBF

    Science.gov (United States)

    Imai, Muneaki

    2014-09-01

    We used the 122Sn(d,3He) reaction at T d = 500 MeV to measure the binding energy of 121Sn and pion at RIKEN RIBF. To identify 3He and determine its momentum, we installed TOF-counters and MWDCs at the focal planes of BigRIPS. The TOF-counters worked as particle identifier and triggered the MWDCs, and the MWDCs enabled us to detect the incident position of 3He. The TOF-counters consisted of two groups set in upper (F5-counter) and lower (F7) streams. The F5-counter, which worked under severe rate environment, was segmented into two pieces of plastic scintillators (240*45*3.2 mm) with two PMTs on left and right edges. We conducted F5-counter calibration by using a 90Sr source to get the ideal gain by setting a proper impressed voltage to the PMTs, so that we could successfully distinguish 3He from intense backgrounds of proton and deuteron by determining an appropriate discriminator threshold. We used the 122Sn(d,3He) reaction at T d = 500 MeV to measure the binding energy of 121Sn and pion at RIKEN RIBF. To identify 3He and determine its momentum, we installed TOF-counters and MWDCs at the focal planes of BigRIPS. The TOF-counters worked as particle identifier and triggered the MWDCs, and the MWDCs enabled us to detect the incident position of 3He. The TOF-counters consisted of two groups set in upper (F5-counter) and lower (F7) streams. The F5-counter, which worked under severe rate environment, was segmented into two pieces of plastic scintillators (240*45*3.2 mm) with two PMTs on left and right edges. We conducted F5-counter calibration by using a 90Sr source to get the ideal gain by setting a proper impressed voltage to the PMTs, so that we could successfully distinguish 3He from intense backgrounds of proton and deuteron by determining an appropriate discriminator threshold. Student poster.

  18. A new type counter electrode for dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    JI WeiWei; CAI Ning; ZHAO Ying; ZHANG XiaoDan; SUN Jian; WEI ChangChun; YUAN CunDa; LI Yuan; SU Yan; XIONG ShaoZhen

    2009-01-01

    A new type counter electrode for dye-sensitized solar cells (DSCs) was proposed which consists of aubstrate, aluminum film and platinum film. The new type counter electrode can obviously improve the photoelectric conversion efficiency of DSCs from 3.46% to 7.07% under the standard AM1.5 irradiation condition. Advantages and shortcomings of this new type counter electrode in terms of electrical properties, optical properties and anti-corrosive properties were analyzed. As a result, some improvements were proposed.

  19. A new optical ice particle counter at LACIS

    Science.gov (United States)

    Bieligk, Henner; Voelker, Georg Sebastian; Clauss, Tina; Grundmann, Marius; Stratmann, Frank

    2014-05-01

    Clouds play an important role within the climate system, especially for the radiative energy budget of the earth. The radiative properties of a cloud depend strongly on the fractions of ice crystals and water droplets, their size distributions, and the ice crystal shapes within the particular cloud. One option to gain this kind of information is using optical particle counters. A new optical particle counter is developed for laboratory work and is based on the concept of the Thermostabilized Optical Particle Spectrometer for the Detection of Ice Particles (TOPS-Ice, Clauss et al., 2013). TOPS-Ice uses linearly polarized green laser light and the depolarization of the scattered light at a scattering angle of 42.5° to discriminate between liquid water droplets and ice crystals in the lower μm range. However, the measurements are usually limited to ice fractions in the order of 1%. To improve the determination of the ice fraction, several modifications of the original setup are implemented including an additional detection system at another scattering angle. The new scattering angle is optimized for least interference between the droplet and ice signals. This is achieved by finding the angle with the maximum difference in scattered intensity of water droplets compared to ice crystals with the same volume equivalent diameter. The suitable scattering angle of 100° for linearly polarized light was chosen based on calculations using T-Matrix method, Lorenz-Mie theory, Müller matrices and distribution theory. The new optical setup is designed to run in combination with a laminar flow tube, the so-called Leipzig Aerosol Cloud Interaction Simulator (LACIS, Stratmann et al., 2004; Hartmann et al., 2011). Using LACIS and its precisely controlled thermodynamic conditions, we are able to form small water droplets and ice crystals which will then be detected, classified and sized by our new optical device. This setup is planned to be tested in ice measurements including

  20. Syndromic Surveillance of Norovirus Using over the Counter Sales of Medications related to Gastrointestinal Illness

    Directory of Open Access Journals (Sweden)

    Victoria L Edge

    2006-01-01

    Full Text Available OBJECTIVE: To assess whether over-the-counter (OTC sales of gastrointestinal illness (GI-related medications are associated with temporal trends of reportable community viral, bacterial and parasitic infections.

  1. Modeling and Simulation of a Counter-Rotating Turbine System for Underwater Vehicles

    Institute of Scientific and Technical Information of China (English)

    Xinping Wang; Jianjun Dang

    2016-01-01

    The structure of a counter-rotating turbine of an underwater vehicle is designed by adding the counter-rotating second-stage turbine disk to the conventional single-stage turbine. The available kinetic energy and the absorption power of the auxiliary system are calculated at different working conditions, and the results show that the power of the main engine and auxiliary system at the counter-rotating turbine system matches well with each other. The technology scheme of the counter-rotating turbine system is proposed, then the experimental simulation of the lubricating oil loop, fuel loop, and seawater loop is completed. The simulation results indicate that the hydraulic transmission system can satisfy the requirements for an underwater vehicle running at a steady sailing or variable working conditions.

  2. Calibration methodology for proportional counters applied to yield measurements of a neutron burst

    Energy Technology Data Exchange (ETDEWEB)

    Tarifeño-Saldivia, Ariel, E-mail: atarifeno@cchen.cl, E-mail: atarisal@gmail.com; Pavez, Cristian; Soto, Leopoldo [Comisión Chilena de Energía Nuclear, Casilla 188-D, Santiago (Chile); Center for Research and Applications in Plasma Physics and Pulsed Power, P4, Santiago (Chile); Departamento de Ciencias Fisicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Republica 220, Santiago (Chile); Mayer, Roberto E. [Instituto Balseiro and Centro Atómico Bariloche, Comisión Nacional de Energía Atómica and Universidad Nacional de Cuyo, San Carlos de Bariloche R8402AGP (Argentina)

    2014-01-15

    This paper introduces a methodology for the yield measurement of a neutron burst using neutron proportional counters. This methodology is to be applied when single neutron events cannot be resolved in time by nuclear standard electronics, or when a continuous current cannot be measured at the output of the counter. The methodology is based on the calibration of the counter in pulse mode, and the use of a statistical model to estimate the number of detected events from the accumulated charge resulting from the detection of the burst of neutrons. The model is developed and presented in full detail. For the measurement of fast neutron yields generated from plasma focus experiments using a moderated proportional counter, the implementation of the methodology is herein discussed. An experimental verification of the accuracy of the methodology is presented. An improvement of more than one order of magnitude in the accuracy of the detection system is obtained by using this methodology with respect to previous calibration methods.

  3. Lossless Compression Performance of a Simple Counter-Based Entropy Coder

    Directory of Open Access Journals (Sweden)

    Armein Z.R. Langi

    2013-09-01

    Full Text Available This paper describes the performance of a simple counter based entropy coder XE "entropy coder" , as compared to other entropy coders, especially Huffman coder. Lossless data compression, such as Huffman coder and arithmetic coder, are designed to perform well over a wide range of data entropy. As a result, the coders require significant computational resources that could be the bottleneck of a compression implementation performance. In contrast, counter-based coders are designed to be optimal on a limited entropy range only. This paper shows the encoding and decoding process of counter-based coder XE "counter-based coder"  can be simple and fast, very suitable for hardware and software implementations. It also reports that the performance of the designed coder is comparable to that of a much more complex Huffman coder.

  4. INVESTIGATION OF TURBULENCE STRUCTURES AND TURBULENT COUNTER-GRADIENT TRANSPORT PROPERTIES IN STRATIFIED FLOWS

    Institute of Scientific and Technical Information of China (English)

    QIU Xiang

    2006-01-01

    Turbulence structures and turbulent Counter-Gradient Transport(CGT) properties in the stratified flows with a sharp temperature interface are investigated by experimental measurements using LIF and PIV, by LES and by correlation analysis.

  5. Modeling and simulation of a counter-rotating turbine system for underwater vehicles

    Science.gov (United States)

    Wang, Xinping; Dang, Jianjun

    2016-12-01

    The structure of a counter-rotating turbine of an underwater vehicle is designed by adding the counter-rotating second-stage turbine disk after the conventional single-stage turbine. The available kinetic energy and the absorption power of the auxiliary system are calculated at different working conditions, and the results show that the power of the main engine and auxiliary system at the counter-rotating turbine system matches well with each other. The experimental simulation of the lubricating oil loop, fuel loop, and seawater loop are completed right before the technology scheme of the counter-rotating turbine system is proposed. The simulation results indicate that the hydraulic transmission system can satisfy the requirements for an underwater vehicle running at a steady sailing or variable working conditions.

  6. Validation of an automated mite counter for Dermanyssus gallinae in experimental laying hen cages.

    Science.gov (United States)

    Mul, Monique F; van Riel, Johan W; Meerburg, Bastiaan G; Dicke, Marcel; George, David R; Groot Koerkamp, Peter W G

    2015-08-01

    For integrated pest management (IPM) programs to be maximally effective, monitoring of the growth and decline of the pest populations is essential. Here, we present the validation results of a new automated monitoring device for the poultry red mite (Dermanyssus gallinae), a serious pest in laying hen facilities world-wide. This monitoring device (called an "automated mite counter") was validated in experimental laying hen cages with live birds and a growing population of D. gallinae. This validation study resulted in 17 data points of 'number of mites counted' by the automated mite counter and the 'number of mites present' in the experimental laying hen cages. The study demonstrated that the automated mite counter was able to track the D. gallinae population effectively. A wider evaluation showed that this automated mite counter can become a useful tool in IPM of D. gallinae in laying hen facilities.

  7. Calibration methodology for proportional counters applied to yield measurements of a neutron burst.

    Science.gov (United States)

    Tarifeño-Saldivia, Ariel; Mayer, Roberto E; Pavez, Cristian; Soto, Leopoldo

    2014-01-01

    This paper introduces a methodology for the yield measurement of a neutron burst using neutron proportional counters. This methodology is to be applied when single neutron events cannot be resolved in time by nuclear standard electronics, or when a continuous current cannot be measured at the output of the counter. The methodology is based on the calibration of the counter in pulse mode, and the use of a statistical model to estimate the number of detected events from the accumulated charge resulting from the detection of the burst of neutrons. The model is developed and presented in full detail. For the measurement of fast neutron yields generated from plasma focus experiments using a moderated proportional counter, the implementation of the methodology is herein discussed. An experimental verification of the accuracy of the methodology is presented. An improvement of more than one order of magnitude in the accuracy of the detection system is obtained by using this methodology with respect to previous calibration methods.

  8. Effects of diluents on cell culture viability measured by automated cell counter

    National Research Council Canada - National Science Library

    Aaron Chen; Matthew Leith; Roger Tu; Gurpreet Tahim; Anish Sudra; Swapnil Bhargava

    2017-01-01

      Commercially available automated cell counters based on trypan blue dye-exclusion are widely used in industrial cell culture process development and manufacturing to increase throughput and eliminate...

  9. Anti-money laundering and countering the financing of terrorism--the Reserve Bank's supervisory approach

    National Research Council Canada - National Science Library

    Armstrong, Hamish

    2012-01-01

    In September 2010, a Bulletin article set out the Reserve Bank of New Zealand's role and responsibilities with regard to the Anti-Money Laundering and Countering Financing of Terrorism Act 2009 ("the Act...

  10. A 3He counter version of the Thermo Fisher Scientific NRD neutron rem meter.

    Science.gov (United States)

    Olsher, Richard H; Seagraves, David T

    2008-01-01

    Thermo Fisher Scientific's NRD rem meter has been in production for almost 40 y and is the primary rem meter in use at many U.S. Department of Energy facilities. An upgrade project was initiated at the Los Alamos National Laboratory with the primary goal of increasing the NRD's neutron sensitivity through the substitution of pressurized 3He gas (4 atmospheres) for the stock counter tube's BF3 fill gas. Historically, BF3 counters were far less expensive relative to 3He and were usually chosen on the basis of cost. That is no longer the case, with pricing for both types of counters being similar. Test results have shown that the 3He counter version of the NRD exhibits stable operation at a reasonable bias voltage and good gamma rejection. Sensitivity has been increased by about a factor of four with no penalty in cost.

  11. On the Performance of Counter-Based Broadcast Scheme for Mobile ...

    African Journals Online (AJOL)

    acer

    determining an optimal counter threshold-value using a network setting with very low traffic load. In this paper, we ... communications between participating mobile devices with ... network. It is a fundamental operation which is extensively used.

  12. The cognitive costs of the counter-stereotypic: gender, emotion, and social presence.

    Science.gov (United States)

    McCarty, Megan K; Kelly, Janice R; Williams, Kipling D

    2014-01-01

    We explored the concurrent and subsequent cognitive consequences of the experience of gender counter-stereotypic emotions. Participants experiencing gender counter-stereotypic emotions were expected to display less emotional expression and demonstrate poorer cognitive performance when in the public condition than when in the private condition. Seventy-one women and 66 men completed an anger- or sadness-inducing task privately or publicly. Participants completed two cognitive tasks: one during and one after the emotion-induction task. Participants exhibited poorer performance during and following gender counter-stereotypic emotions only in the public condition. Direct evidence for greater suppression of gender counter-stereotypic emotions in the public conditions was not obtained. These results suggest that the same public emotional events may be differentially cognitively depleting depending on one's gender, potentially contributing to the perpetuation of stereotypes.

  13. New Zealand parent's perceptions of the use and safety of over the counter liquid analgesics

    National Research Council Canada - National Science Library

    Sarah K Bushby; Rachel J Anderson; Rhiannon Braund

    2010-01-01

    Objective: The objective of this study was to investigate the knowledge of parents and caregivers with respect to the purchase, use and storage of liquid analgesics purchased over the counter (OTC) from pharmacies...

  14. The Heritability of Antinociception II: Pharmacogenetic Mediation of Three Over-the-Counter Analgesics in Mice

    National Research Council Canada - National Science Library

    Sonya G. Wilson; Camron D. Bryant; William R. Lariviere; Michael S. Olsen; Belinda E. Giles; Elissa J. Chesler; Jeffrey S. Mogil

    2003-01-01

    Chromosomal loci containing genes affecting antinociceptive sensitivity to morphine have been identified, but virtually nothing is known about the genetic mediation of sensitivity to over-the-counter analgesics...

  15. FIRST ARTICLE ENVIRONMENTAL TESTING OF PORTABLE ALPHA SCINTILLATION COUNTER EQUIPMENT SET. SUPPLEMENT 1.

    Science.gov (United States)

    Three revised Portable Alpha Scintillation Counter Equipment Sets were subjected to tests in accordance with project documentation. Failures incurred by the test items prohibited completion of the test series. (Author)

  16. Carbon Nanotubes Counter Electrode for Dye-Sensitized Solar Cells Application

    Directory of Open Access Journals (Sweden)

    Drygała A.

    2016-06-01

    Full Text Available The influence of the carbon nanotubes counter electrode deposited on the FTO glass substrates on the structure and optoelectrical properties of dye-sensitized solar cells counter electrode (CE was analysed. Carbon materials have been applied in DSSC s in order to produce low-cost solar cells with reasonable efficiency. Platinum is a preferred material for the counter electrode because of its high conductivity and catalytic activity. However, the costs of manufacturing of the platinum counter electrode limit its use to large-scale applications in solar cells. This paper presents the results of examining the structure and properties of the studied layers, defining optical properties of conductive layers and electrical properties of dye-sensitized solar cells manufactured with the use of carbon nanotubes.

  17. Gold nanoparticle decorated multi-walled carbon nanotubes as counter electrode for dye sensitized solar cells.

    Science.gov (United States)

    Kaniyoor, Adarsh; Ramaprabhu, Sundara

    2012-11-01

    A novel counter electrode material for dye sensitized solar cells (DSSCs) composed of nanostructured Au particles decorated on functionalized multi-walled carbon nanotubes (f-MWNTs) is demonstrated for the first time. MWNTs synthesized by catalytic chemical vapor deposition technique are purified and functionalized by treating with concentrated acids. Au nanoparticles are decorated on f-MWNTs by a rapid and facile microwave assisted polyol reduction method. The materials are characterized by X-ray diffractometry, Fourier transform infra red spectroscopy and electron microscopy. The DSSC fabricated with Au/f-MWNTs based counter electrode shows enhanced power conversion efficiency (eta) of 4.9% under AM 1.5G simulated solar radiation. In comparison, the reference DSSCs fabricated with f-MWNTs and Pt counter electrodes show eta of 2.1% and 4.5%. This high performance of Au/f-MWNTs counter electrode is investigated using electrochemical impedance spectroscopy and cyclic voltammetry studies.

  18. The effects of gender stereotypic and counter-stereotypic textbook images on science performance.

    Science.gov (United States)

    Good, Jessica J; Woodzicka, Julie A; Wingfield, Lylan C

    2010-01-01

    We investigated the effect of gender stereotypic and counter-stereotypic images on male and female high school students' science comprehension and anxiety. We predicted stereotypic images to induce stereotype threat in females and impair science performance. Counter-stereotypic images were predicted to alleviate threat and enhance female performance. Students read one of three chemistry lessons, each containing the same text, with photograph content varied according to stereotype condition. Participants then completed a comprehension test and anxiety measure. Results indicate that female students had higher comprehension after viewing counter-stereotypic images (female scientists) than after viewing stereotypic images (male scientists). Male students had higher comprehension after viewing stereotypic images than after viewing counter-stereotypic images. Implications for alleviating the gender gap in science achievement are discussed.

  19. 508.58 MHz synchronous universal counter for beam control system of SPring-8

    CERN Document Server

    Suzuki, H; Hara, M; Hori, T; Kawashima, Y; Ohashi, Y; Ohshima, T; Tani, N; Yonehara, H

    1999-01-01

    A synchronous universal counter was developed for beam handling and monitoring in SPring-8. It works at 508.58 MHz radio frequency and has a 30-bit width. Its two main features are a dividing function with an arbitrary positive integer and a digital delay function with a time interval over 2 s. The counter numbers all of the RF buckets of the SPring-8 storage ring from 0 to 2435. Successful installation of the counter and a signal transmission system with a low time jitters provided precise beam injection into a targeted RF bucket and furthermore into the RF buckets previously filled for addition. As an application, it can be used as a programmable digital delay module to give a reference timing for synchrotron light experiments. It can be adopted in most accelerators operated throughout the world to achieve easy beam injection. The design, performance and applications of the counter and a precise signal transmission system are described. (author)

  20. Calibration and background measurements with a tissue equivalent proportional counter.

    Science.gov (United States)

    Autischer, M; Beck, P; Kindl, P; Latocha, M; Rollet, S

    2007-01-01

    A tissue-equivalent-proportional counter (TEPC) instrument has been used as the reference instrument for cosmic radiation measurement at flight altitudes by several institutes. For purposes of characterisation the response of the instrument has been investigated under different standard radiation conditions, in terms of radiation particle, energy and angle of incidence. Photon sources and photon beams of energies up to 6.6 MeV and neutron beams up to 200 MeV were used. To have a better understanding of the shielding influence of the instrument assembly, the angle dependence of response was analysed for several radiation conditions. Specific measurement conditions were simulated with the Monte Carlo transport code, FLUKA. The measured instrument response was compared with simulation results. It was demonstrated, that simulations were very helpful to understand the instrument's response. The TEPC instrument used by the Austrian Research Centre Seibersdorf (ARCS) research simulates the energy deposition in a unit density tissue volume of 2 microm diameter, of similar size to a cell nucleus. Pure propane at low pressure is used as measurement gas. To characterise the instrument at low dose rates background measurements were done 800 m below ground and at the ultra low level laboratory in Gran Sasso, 1380 m below ground. These results were compared with measurements on the Earth's surface at different altitudes on mountains up to 3480 m above sea level. The significant increase of the expected dose rate is well reproduced by the experiments at mountain altitudes. As a result of this study a full characterisation and a thorough understanding of the performance and reliability of the detector was achieved.