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Sample records for antimycin a

  1. Streptomyces strains producing mitochondriotoxic antimycin A found in cereal grains.

    Science.gov (United States)

    Rasimus-Sahari, Stiina; Mikkola, Raimo; Andersson, Maria A; Jestoi, Marika; Salkinoja-Salonen, Mirja

    2016-02-01

    Reasons for mammalian cell toxicity observed in barley and spring wheat grains were sought. Streptomyces sp. isolates from wheat and barley produced heat-stable methanol-soluble substances which inhibited the motility of exposed porcine spermatozoa used as a toxicity indicator. Several barley isolates produced antimycin A (2 to 5 ng/mg wet wt of biomass), a macrolide antibiotic known to block oxygen utilization in mitochondria. The antimycin-producing isolates were members of the Streptomyces albidoflavus group. In in vitro assays with porcine kidney tubular epithelial cells, the specific toxicity of antimycin A towards mitochondria was higher than that of the mycotoxin enniatin B but lower than that of the mitochondriotoxins cereulide and paenilide, produced by food-related Bacillus cereus and Paenibacillus tundrae, respectively. The toxic wheat isolates, related to Streptomyces sedi, did not produce antimycin A and or any other known toxin. Our results suggest that the presence of toxin-producing streptomycetes in stored cereal grains may pose a thus far unrecognized threat for food and feed safety. PMID:26619316

  2. Two Antimycin A Analogues from Marine-Derived Actinomycete Streptomyces lusitanus

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    Peiyuan Qian

    2012-03-01

    Full Text Available Two new antimycin A analogues, antimycin B1 and B2 (1–2, were isolated from a spent broth of a marine-derived bacterium, Streptomyces lusitanus. The structures of 1 and 2 were established on the basis of spectroscopic analyses and chemical methods. The isolated compounds were tested for their anti-bacterial potency. Compound 1 was found to be inactive against the bacteria Bacillus subtilis, Staphyloccocus aureus, and Loktanella hongkongensis. Compound 2 showed antibacterial activities against S. aureus and L. hongkongensis with MIC values of 32.0 and 8.0 μg/mL, respectively.

  3. Deoxyactein Isolated from Cimicifuga racemosa protects osteoblastic MC3T3-E1 cells against antimycin A-induced cytotoxicity.

    Science.gov (United States)

    Choi, Eun Mi

    2013-06-01

    Deoxyactein is one of the major constituents isolated from Cimicifuga racemosa. In the present study, we investigated the protective effects of deoxyactein on antimycin A (mitochondrial electron transport inhibitor)-induced toxicity in osteoblastic MC3T3-E1 cells. Exposure of MC3T3-E1 cells to antimycin A caused significant cell viability loss, as well as mitochondrial membrane potential dissipation, complex IV inactivation, ATP loss, intracellular calcium ([Ca(2+) ]i ) elevation and oxidative stress. Pretreatment with deoxyactein prior to antimycin A exposure significantly reduced antimycin A-induced cell damage by preventing mitochondrial membrane potential dissipation, complex IV inactivation, ATP loss, [Ca(2+) ]i elevation and oxidative stress. Moreover, deoxyactein increased the activation of PI3K (phosphoinositide 3-kinase), Akt (protein kinase B) and CREB (cAMP-response element-binding protein) inhibited by antimycin A. All these data indicate that deoxyactein may reduce or prevent osteoblasts degeneration in osteoporosis or other degenerative disorders. PMID:22180388

  4. Analysis of antimycin A by reversed-phase liquid chromatography/nuclear magnetic-resonance spectrometry

    Science.gov (United States)

    Ha, Steven T.K.; Wilkins, Charles L.; Abidi, Sharon L.

    1989-01-01

    A mixture of closely related streptomyces fermentation products, antimycin A, Is separated, and the components are identified by using reversed-phase high-performance liquid chromatography with directly linked 400-MHz proton nuclear magnetic resonance detection. Analyses of mixtures of three amino acids, alanine, glycine, and valine, are used to determine optimal measurement conditions. Sensitivity increases of as much as a factor of 3 are achieved, at the expense of some loss in chromatographic resolution, by use of an 80-μL NMR cell, Instead of a smaller 14-μL cell. Analysis of the antimycin A mixture, using the optimal analytical high performance liquid chromatography/nuclear magnetic resonance conditions, reveals it to consist of at least 10 closely related components.

  5. Celastrol Protects against Antimycin A-Induced Insulin Resistance in Human Skeletal Muscle Cells

    OpenAIRE

    Mohamad Hafizi Abu Bakar; Kian-Kai Cheng; Mohamad Roji Sarmidi; Harisun Yaakob; Hasniza Zaman Huri

    2015-01-01

    Mitochondrial dysfunction and inflammation are widely accepted as key hallmarks of obesity-induced skeletal muscle insulin resistance. The aim of the present study was to evaluate the functional roles of an anti-inflammatory compound, celastrol, in mitochondrial dysfunction and insulin resistance induced by antimycin A (AMA) in human skeletal muscle cells. We found that celastrol treatment improved insulin-stimulated glucose uptake activity of AMA-treated cells, apparently via PI3K/Akt pathwa...

  6. Antimycin A treatment decreases respiratory internal rotenone-insensitive NADH oxidation capacity in potato leaves

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    Svensson Å Staffan

    2004-05-01

    Full Text Available Abstract Background The plant respiratory chain contains several energy-dissipating enzymes, these being type II NAD(PH dehydrogenases and the alternative oxidase, not present in mammals. The physiological functions of type II NAD(PH dehydrogenases are largely unclear and little is known about their responses to stress. In this investigation, potato plants (Solanum tuberosum L., cv. Desiree were sprayed with antimycin A, an inhibitor of the cytochrome pathway. Enzyme capacities of NAD(PH dehydrogenases (EC 1.6.5.3 and the alternative oxidase were then analysed in isolated leaf mitochondria. Results We report a specific decrease in internal rotenone-insensitive NADH dehydrogenase capacity in mitochondria from antimycin A-treated leaves. External NADPH dehydrogenase and alternative oxidase capacities remained unaffected by the treatment. Western blotting revealed no change in protein abundance for two characterised NAD(PH dehydrogenase homologues, NDA1 and NDB1, nor for two subunits of complex I. The alternative oxidase was at most only slightly increased. Transcript levels of nda1, as well as an expressed sequence tag derived from a previously uninvestigated closely related potato homologue, remained unchanged by the treatment. As compared to the daily rhythm-regulated nda1, the novel homologue displayed steady transcript levels over the time investigated. Conclusions The internal rotenone-insensitive NADH oxidation decreases after antimycin A treatment of potato leaves. However, the decrease is not due to changes in expression of known nda genes. One consequence of the lower NADH dehydrogenase capacity may be a stabilisation of the respiratory chain reduction level, should the overall capacity of the cytochrome and the alternative pathway be restricted.

  7. The regulation and biosynthesis of antimycins

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    Ryan F. Seipke

    2013-11-01

    Full Text Available Antimycins (>40 members were discovered nearly 65 years ago but the discovery of the gene cluster encoding antimycin biosynthesis in 2011 has facilitated rapid progress in understanding the unusual biosynthetic pathway. Antimycin A is widely used as a piscicide in the catfish farming industry and also has potent killing activity against insects, nematodes and fungi. The mode of action of antimycins is to inhibit cytochrome c reductase in the electron transport chain and halt respiration. However, more recently, antimycin A has attracted attention as a potent and selective inhibitor of the mitochondrial anti-apoptotic proteins Bcl-2 and Bcl-xL. Remarkably, this inhibition is independent of the main mode of action of antimycins such that an artificial derivative named 2-methoxyantimycin A inhibits Bcl-xL but does not inhibit respiration. The Bcl-2/Bcl-xL family of proteins are over-produced in cancer cells that are resistant to apoptosis-inducing chemotherapy agents, so antimycins have great potential as anticancer drugs used in combination with existing chemotherapeutics. Here we review what is known about antimycins, the regulation of the ant gene cluster and the unusual biosynthetic pathway.

  8. A Preclinical Evaluation of Antimycin A as a Potential Antilung Cancer Stem Cell Agent

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    Chi-Tai Yeh

    2013-01-01

    Full Text Available Drug resistance and tumor recurrence are major obstacles in treating lung cancer patients. Accumulating evidence considers lung cancer stem cells (CSCs as the major contributor to these clinical challenges. Agents that can target lung CSCs could potentially provide a more effective treatment than traditional chemotherapy. Here, we utilized the side-population (SP method to isolate lung CSCs from A549 and PC-9 cell lines. Subsequently, a high throughput platform, connectivity maps (CMAPs, was used to identify potential anti-CSC agents. An antibiotic, antimycin A (AMA, was identified as a top candidate. SP A549 cells exhibited an elevated stemness profile, including Nanog, β-catenin, Sox2, and CD133, and increased self-renewal ability. AMA treatment was found to suppress β-catenin signaling components and tumor sphere formation. Furthermore, AMA treatment decreased the proliferation of gefitinib-resistant PC-9/GR cells and percentage of SP population. AMA demonstrated synergistic suppression of PC-9/GR cell viability when combined with gefitinib. Finally, AMA treatment suppressed tumorigenesis in mice inoculated with A549 SP cells. Collectively, we have identified AMA using CMAP as a novel antilung CSC agent, which acts to downregulate β-catenin signaling. The combination of AMA and targeted therapeutic agents could be considered for overcoming drug resistance and relapse in lung cancer patients.

  9. Celastrol Protects against Antimycin A-Induced Insulin Resistance in Human Skeletal Muscle Cells

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    Mohamad Hafizi Abu Bakar

    2015-05-01

    Full Text Available Mitochondrial dysfunction and inflammation are widely accepted as key hallmarks of obesity-induced skeletal muscle insulin resistance. The aim of the present study was to evaluate the functional roles of an anti-inflammatory compound, celastrol, in mitochondrial dysfunction and insulin resistance induced by antimycin A (AMA in human skeletal muscle cells. We found that celastrol treatment improved insulin-stimulated glucose uptake activity of AMA-treated cells, apparently via PI3K/Akt pathways, with significant enhancement of mitochondrial activities. Furthermore, celastrol prevented increased levels of cellular oxidative damage where the production of several pro-inflammatory cytokines in cultures cells was greatly reduced. Celastrol significantly increased protein phosphorylation of insulin signaling cascades with amplified expression of AMPK protein and attenuated NF-κB and PKC θ activation in human skeletal muscle treated with AMA. The improvement of insulin signaling pathways by celastrol was also accompanied by augmented GLUT4 protein expression. Taken together, these results suggest that celastrol may be advocated for use as a potential therapeutic molecule to protect against mitochondrial dysfunction-induced insulin resistance in human skeletal muscle cells.

  10. Antimycin-insensitive mutants of Candida utilis II. The effects of antimycin on Cytochrome b

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, C J; Marres, C A; Slater, Conor

    1975-01-01

    . 5. The difference between the effect of antimycin on electron transport and cytochromes b reduction is also found in intact cells of the mutant. 6. A model is suggested for the wild-type respiratory chain in which (i) the cytochromes b lie, in an uncoupled system, out of the main electron......-transfer chain, (ii) antimycin induces a conformation change in QH-2-cytochrome c reductase resulting in effects on cytochrome b and inhibition of electron transport, (iii) a second antimycin-binding site with low affinity to the antibiotic is present, capable of inhibiting electron transport....... reoxidation is observed in the wild type in the present of low concentrations of antimycin. 2. In contrast to the wild type, inhibition of electron transport in the mutant has a much higher antimycin titre than effects on cytochromes b (viz., aerobic steady-state reduction; reduction in the presence of...

  11. Binding of the Respiratory Chain Inhibitor Antimycin to theMitochondrial bc1 Complex: A New Crystal Structure Reveals an AlteredIntramolecular Hydrogen-Bonding Pattern

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Li-shar; Cobessi, David; Tung, Eric Y.; Berry, Edward A.

    2005-05-10

    Antimycin A (antimycin), one of the first known and most potent inhibitors of the mitochondrial respiratory chain, binds to the quinone reduction site of the cytochrome bc1 complex.Structure-activity-relationship studies have shown that the N-formylamino-salicyl-amide group is responsible for most of the binding specificity, and suggested that a low pKa for the phenolic OH group and an intramolecular H-bond between that OH and the carbonyl O of the salicylamide linkage are important. Two previous X-ray structures of antimycin bound to vertebrate bc1 complex gave conflicting results. A new structure reported here of the bovine mitochondrial bc1 complex at 2.28Angstrom resolution with antimycin bound, allows us for the first time to reliably describe the binding of antimycin and shows that the intramolecular hydrogen bond described in solution and in the small-molecule structure is replaced by one involving the NH rather than carbonyl O of the amide linkage, with rotation of the amide group relative to the aromatic ring. The phenolic OH and formylamino N form H-bonds with conserved Asp228 of cyt b, and the formylamino O H-bonds via a water molecule to Lys227. A strong density the right size and shape for a diatomic molecule is found between the other side of the dilactone ring and the alpha-A helix.

  12. Redox regulation of the antimycin A sensitive pathway of cyclic electron flow around photosystem I in higher plant thylakoids.

    Science.gov (United States)

    Strand, Deserah D; Fisher, Nicholas; Davis, Geoffry A; Kramer, David M

    2016-01-01

    The chloroplast must regulate supply of reducing equivalents and ATP to meet rapid changes in downstream metabolic demands. Cyclic electron flow around photosystem I (CEF) is proposed to balance the ATP/NADPH budget by using reducing equivalents to drive plastoquinone reduction, leading to the generation of proton motive force and subsequent ATP synthesis. While high rates of CEF have been observed in vivo, isolated thylakoids show only very slow rates, suggesting that the activity of a key complex is lost or down-regulated upon isolation. We show that isolation of thylakoids while in the continuous presence of reduced thiol reductant dithiothreitol (DTT), but not oxidized DTT, maintains high CEF activity through an antimycin A sensitive ferredoxin:quinone reductase (FQR). Maintaining low concentrations (~2 mM) of reduced DTT while modulating the concentration of oxidized DTT leads to reversible activation/inactivation of CEF with an apparent midpoint potential of -306 mV (±10 mV) and n=2, consistent with redox modulation of a thiol/disulfide couple and thioredoxin-mediated regulation of the plastoquinone reductase involved in the antimycin A-sensitive pathway, possibly at the level of the PGRL1 protein. Based on proposed differences in regulatory modes, we propose that the FQR and NADPH:plastoquinone oxidoreductase (NDH) pathways for CEF are activated under different conditions and fulfill different roles in chloroplast energy balance. PMID:26235611

  13. BINDING OF THE RESPIRATORY CHAIN INHIBITOR ANTIMYCIN TO THE MITOCHONDRIAL bc1 COMPLEX: A NEW CRYSTAL STRUCTURE REVEALS AN ALTERED INTRAMOLECULAR HYDROGEN-BONDING PATTERN.

    OpenAIRE

    Huang, Li-shar; Cobessi, David; Tung, Eric Y.; Berry, Edward A.

    2005-01-01

    Antimycin A (antimycin), one of the first known and most potent inhibitors of the mitochondrial respiratory chain, binds to the quinone reduction site of the cytochrome bc1 complex. Structure-activity-relationship studies have shown that the N-formylamino-salicyl-amide group is responsible for most of the binding specificity, and suggested that a low pKa for the phenolic OH group and an intramolecular H-bond between that OH and the carbonyl O of the salicylamide linkage are important. Tw...

  14. Bypasses of the antimycin a block of mitochondrial electron transport in relation to ubisemiquinone function.

    Science.gov (United States)

    Alexandre, A; Lehninger, A L

    1984-10-26

    Two different bypasses around the antimycin block of electron transport from succinate to cytochrome c via the ubiquinol-cytochrome c oxidoreductase of intact rat liver mitochondria were analyzed, one promoted by N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) and the other by 2,6-dichlorophenolindophenol (DCIP). Both bypasses are inhibited by myxothiazol, which blocks electron flow from ubiquinol to the Rieske iron-sulfur center, and by 2-hydroxy-3-undecyl-1,4-naphthoquinone, which inhibits electron flow from the iron-sulfur center to cytochrome c1. In the bypass promoted by TMPD its oxidized form (Wurster's blue) acts as an electron acceptor from some reduced component prior to the antimycin block, which by exclusion of other possibilities is ubisemiquinone. In the DCIP bypass its reduced form acts as an electron donor, by reducing ubisemiquinone to ubiquinol; reduced DCIP is regenerated again at the expense of either succinate or ascorbate. The observations described are consistent with and support current models of the Q cycle. Bypasses promoted by artificial electron carriers provide an independent approach to analysis of electron flow through ubiquinol-cytochrome c oxidoreductase. PMID:6091750

  15. Determination of Antimycin-A in water by liquid chromatographic/mass spectrometry: single-laboratory validation

    Science.gov (United States)

    Bernardy, Jeffry A.; Hubert, Terrance D.; Ogorek, Jacob M.; Schmidt, Larry J.

    2013-01-01

    An LC/MS method was developed and validated for the quantitative determination and confirmation of antimycin-A (ANT-A) in water from lakes or streams. Three different water sample volumes (25, 50, and 250 mL) were evaluated. ANT-A was stabilized in the field by immediately extracting it from water into anhydrous acetone using SPE. The stabilized concentrated samples were then transported to a laboratory and analyzed by LC/MS using negative electrospray ionization. The method was determined to have adequate accuracy (78 to 113% recovery), precision (0.77 to 7.5% RSD with samples ≥500 ng/L and 4.8 to 17% RSD with samples ≤100 ng/L), linearity, and robustness over an LOQ range from 8 to 51 600 ng/L.

  16. U.S.D.A. Forest Service environmental analysis report on the use of antimycin to rehabilitate lakes and streams

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Report identifies characteristics of use of antimycin to destroy stickleback, chub, suckers and other competitors to salmon and dolly varden.

  17. Studies on intracellular transport of secretory proteins in the rat exocrine pancreas. III. Effect of cobalt, lanthanum and antimycin A.

    Science.gov (United States)

    Bieger, W; Seybold, J; Kern, H F

    1975-11-28

    The effects of cobalt and lanthanum on the secretory process of the rat exocrine pancreas was studied in vitro using isolated pancreatic lobules. Cobalt in concentrations between 10(-3) to 10(-5) M has no effect on the rate of protein synthesis, intracellular transport, or discharge of zymogen granules, if the total population of stored granules is considered. It has, however, a marked effect on the release of newly packed zymogen granules which are formed during incubation in 10(-3) M CoC1(2). Determination of specific radioactivity in amylase released under the stimulation of 5X10(-6) M carbamylcholine and of total proteins retained in the zymogen granule fraction during stimulation indicate that granules formed during incubation in CoC1(2) are excluded from discharge. Lanthanum, on the other hand, has a differential effect on protein synthesis, intracellular transport, and discharge. Incorporation of tritiated leucine into TCA-precipitable proteins is inhibited by 50% at 10(-3) M LaC1(3). Intracellular transport as studied by cell fractionation is not changed during the first 35 min post pulse but is delayed from then on. This late effect is more pronounced if pancreatic lobules are preincubated for 60 min in 10(-3) M LaC1(3). Discharge of amylase and newly synthesized proteins is inhibited dose-dependently up to 80% by 10(-3) M LaC1(3). The effects of both cobalt and lanthanum are not due to an inhibition of cellular respiration. Comparison of these results with the inhibitory action of antimycin A between 10(-4) to 10(-8) M concentrations reveals a dose-dependent diminution of the rate of protein synthesis and intracellular transport, while discharge of granules is less energy dependent. The fine structural appearance of pancreatic lobules after 3 hrs incubation in 10(-3) M CoC1(2) is not altered, while in 5X10(-3) and 10(-3) M lanthanum acinar lumina are enlarged and the apical cytoplasm contains large vacuoles. At the highest concentration of lanthanum a

  18. All-Atom Molecular Dynamics Simulations Reveal Significant Differences in Interaction between Antimycin and Conserved Amino Acid Residues in Bovine and Bacterial bc1 Complexes

    OpenAIRE

    Kokhan, Oleksandr; Shinkarev, Vladimir P.

    2011-01-01

    Antimycin A is the most frequently used specific and powerful inhibitor of the mitochondrial respiratory chain. We used all-atom molecular dynamics (MD) simulations to study the dynamic aspects of the interaction of antimycin A with the Qi site of the bacterial and bovine bc1 complexes embedded in a membrane. The MD simulations revealed considerable conformational flexibility of antimycin and significant mobility of antimycin, as a whole, inside the Qi pocket. We conclude that many of the dif...

  19. Effects of thyroid hormones on the bypasses of the antimycin A block in the bc1 complex of rat liver mitochondria.

    Science.gov (United States)

    Horrum, M A; Tobin, R B; Ecklund, R E

    1991-07-15

    The effect of thyroid hormones on the electron flow through the bc1 complex of rat liver mitochondria was studied using two dye bypasses of the Antimycin A block of the bc1 complex by the method of Alexandre and Lehninger (Biochim. Biophys. Acta 767:120; 1984). Bypass respiration rates with both DCIP (2,6-dichlorophenolindophenol) and TMPD (N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride) were elevated in the hyperthyroid rats and depressed in the hypothyroid groups compared to the euthyroid controls. T3 treatment of hypothyroid rats returned the bypass rates to control levels in 24 hours with the TMPD dye but not for the DCIP. This further demonstrates that different portions of the bc1 complex respond individually to the thyroid state. PMID:1648915

  20. 31P NMR saturation-transfer measurements in Saccharomyces cerevisiae: characterization of phosphate exchange reactions by iodoacetate and antimycin A inhibition

    International Nuclear Information System (INIS)

    31P nuclear magnetic resonance (NMR) saturation-transfer (ST) techniques have been used to measure steady-state flows through phosphate-adenosine 5'-triphosphate (ATP) exchange reactions in glucose-grown derepressed yeast. The results have revealed that the reactions catalyzed by glyceraldehyde-3-phosphate dehydrogenase/phosphoglycerate kinase (GAPDH/PGK) and by the mitochondrial ATPase contribute to the observed ST. Contributions from these reactions were evaluated by performing ST studies under various metabolic conditions in the presence and absence of either iodoacetate, a specific inhibitor of GAPDH, or the respiratory chain inhibitor antimycin A. Intracellular phosphate (P/sub i/) longitudinal relaxation times were determined by performing inversion recovery experiments during steady-state ATP/sub λ/ saturation and were used in combination with ST data to determine P/sub i/ consumption rates. 13C NMR and O2 electrode measurements were also conducted to monitor changes in rates of glucose consumption and O2 consumption, respectively, under the various metabolic conditions examined. The results suggest that GAPDH/PGK-catalyzed P/sub i/-ATP exchange is responsible for antimycin-resistant saturation transfer observed in anaerobic and aerobic glucose-fed yeast. Kinetics through GAPDH/PGK were found to depend on metabolic conditions. The coupled system appears to operate in a unidirectional manner during anaerobic glucose metabolism and bidirectionally when the cells are respiring on exogenously supplied ethanol. Additionally, mitochondrial ATPase activity appears to be responsible for the transfer observed in iodoacetate-treated aerobic cells supplied with either glucose or ethanol, with synthesis of ATP occurring unidirectionally

  1. Physiological Concentration of Exogenous Lactate Reduces Antimycin A Triggered Oxidative Stress in Intestinal Epithelial Cell Line IPEC-1 and IPEC-J2 In Vitro

    Science.gov (United States)

    Kahlert, Stefan; Junnikkala, Sami; Renner, Lydia; Hynönen, Ulla; Hartig, Roland; Nossol, Constanze; Barta-Böszörményi, Anikó; Dänicke, Sven; Souffrant, Wolfgang-Bernhard; Palva, Airi; Rothkötter, Hermann-Josef; Kluess, Jeannette

    2016-01-01

    Weaning triggers an adaptation of the gut function including luminal lactate generation by lactobacilli, depending on gastrointestinal site. We hypothesized that both lactobacilli and lactate influence porcine intestinal epithelial cells. In vivo experiments showed that concentration of lactate was significantly higher in gastric, duodenal and jejunal chyme of suckling piglets compared to their weaned counterparts. In an in vitro study we investigated the impact of physiological lactate concentration as derived from the in vivo study on the porcine intestinal epithelial cells IPEC-1 and IPEC-J2. We detected direct adherence of lactobacilli on the apical epithelial surface and a modulated F-actin structure. Application of lactobacilli culture supernatant alone or lactate (25 mM) at low pH (pH 4) changed the F-actin structure in a similar manner. Treatment of IPEC cultures with lactate at near neutral pH resulted in a significantly reduced superoxide-generation in Antimycin A-challenged cells. This protective effect was nearly completely reversed by inhibition of cellular lactate uptake via monocarboxylate transporter. Lactate treatment enhanced NADH autofluorescence ratio (Fcytosol/Fnucleus) in non-challenged cells, indicating an increased availability of reduced nucleotides, but did not change the overall ATP content of the cells. Lactobacilli-derived physiological lactate concentration in intestine is relevant for alleviation of redox stress in intestinal epithelial cells. PMID:27054581

  2. Increased sensitivity of photosynthesis to antimycin A induced by inactivation of the chloroplast ndhB gene. Evidence for a participation of the NADH-dehydrogenase complex to cyclic electron flow around photosystem I.

    Science.gov (United States)

    Joët, T; Cournac, L; Horvath, E M; Medgyesy, P; Peltier, G

    2001-04-01

    Tobacco (Nicotiana tabacum var Petit Havana) ndhB-inactivated mutants (ndhB-) obtained by plastid transformation (E.M. Horvath, S.O. Peter, T. Joët, D. Rumeau, L. Cournac, G.V. Horvath, T.A. Kavanagh, C. Schäfer, G. Peltier, P. MedgyesyHorvath [2000] Plant Physiol 123: 1337-1350) were used to study the role of the NADH-dehydrogenase complex (NDH) during photosynthesis and particularly the involvement of this complex in cyclic electron flow around photosystem I (PSI). Photosynthetic activity was determined on leaf discs by measuring CO2 exchange and chlorophyll fluorescence quenchings during a dark-to-light transition. In the absence of treatment, both non-photochemical and photochemical fluorescence quenchings were similar in ndhB- and wild type (WT). When leaf discs were treated with 5 microM antimycin A, an inhibitor of cyclic electron flow around PSI, both quenchings were strongly affected. At steady state, maximum photosynthetic electron transport activity was inhibited by 20% in WT and by 50% in ndhB-. Under non-photorespiratory conditions (2% O2, 2,500 microL x L(-1) CO2), antimycin A had no effect on photosynthetic activity of WT, whereas a 30% inhibition was observed both on quantum yield of photosynthesis assayed by chlorophyll fluorescence and on CO2 assimilation in ndhB-. The effect of antimycin A on ndhB- could not be mimicked by myxothiazol, an inhibitor of the mitochondrial cytochrome bc1 complex, therefore showing that it is not related to an inhibition of the mitochondrial electron transport chain but rather to an inhibition of cyclic electron flow around PSI. We conclude to the existence of two different pathways of cyclic electron flow operating around PSI in higher plant chloroplasts. One of these pathways, sensitive to antimycin A, probably involves ferredoxin plastoquinone reductase, whereas the other involves the NDH complex. The absence of visible phenotype in ndhB- plants under normal conditions is explained by the complement of these two

  3. Chemosensitization of aflatoxigenic fungi to antimycin A and strobilurin using salicylaldehyde, a volatile natural compound targeting cellular antioxidation system

    Science.gov (United States)

    Salicylaldehyde (SA), a volatile natural compound, exhibited potent antifungal and antiaflatoxigenic activities to Aspergillus flavus and A. parasiticus. Exposure to volatilized SA, inhibited growth of A. parasiticus from 10% - 75% at 9.5 - 16.0 mM, with complete inhibition at 19.0 mM. Similar trend...

  4. Ferredoxin-dependent and antimycin A-sensitive reduction of cytochrome b-559 by far-red light in maize [Zea mays] thylakoids; participation of a meladiol-reducible cytochrome b-559 in cyclic electron flow

    International Nuclear Information System (INIS)

    Thylakoids from mesophyll cells of maize showed a high rate of the ferredoxin (Fd)-dependent and antimycin A (AntiA)-sensitive cyclic electron flow as determined by the quenching of 9-aminoacridine fluorescence which indicates the formation of ΔpH across the membranes. Spectrophotometric survey of the thylakoids showed the reduction of a Cyt having an α-peak at 559 nm [Cyt b-559(Fd)] by far-red light, which depended on Fd and was sensitive to AntiA. Dose dependencies of Fd and AntiA on the photoreduction of Cyt b-559(Fd) were the same as those of the formation of ΔpH. Cyt b-559(Fd) occurred in an oxidized form even in the presence of ascorbate and was reduced by far-red light. In darkness, it was reduced only by menadiol (Em,7 = –10mV). Thus, Cyt b-559(Fd) was distinguished from Cyt b-559 in the PSII complex by its low redox potential. The present results indicate that Cyt b-559(Fd) mediates electron transfer from Fd to plastoquinone during Fd-dependent cyclic electron flow around PSI. (author)

  5. Nitric oxide interacts with mitochondrial complex III producing antimycin-like effects.

    Science.gov (United States)

    Iglesias, Darío E; Bombicino, Silvina S; Valdez, Laura B; Boveris, Alberto

    2015-12-01

    The effect of NO between cytochromes b and c of the mitochondrial respiratory chain were studied using submitochondrial particles (SMP) from bovine heart and GSNO and SPER-NO as NO sources. Succinate-cytochrome c reductase (complex II-III) activity (222 ± 4 nmol/min. mg protein) was inhibited by 51% in the presence of 500 μM GSNO and by 48% in the presence of 30 μM SPER-NO, in both cases at ~1.25 μM NO. Neither GSNO nor SPER-NO were able to inhibit succinate-Q reductase activity (complex II; 220 ± 9 nmol/min. mg protein), showing that NO affects complex III. Complex II-III activity was decreased (36%) when SMP were incubated with l-arginine and mtNOS cofactors, indicating that this effect is also produced by endogenous NO. GSNO (500 μM) reduced cytochrome b562 by 71%, in an [O2] independent manner. Hyperbolic increases in O2(•-) (up to 1.3 ± 0.1 nmol/min. mg protein) and H2O2 (up to 0.64 ± 0.05 nmol/min. mg protein) productions were observed with a maximal effect at 500 μM GSNO. The O2(•-)/H2O2 ratio was 1.98 in accordance with the stoichiometry of the O2(•-) disproportionation. Moreover, H2O2 production was increased by 72-74% when heart coupled mitochondria were exposed to 500 μM GSNO or 30 μM SPER-NO. SMP incubated in the presence of succinate showed an EPR signal (g=1.99) compatible with a stable semiquinone. This EPR signal was increased not only by antimycin but also by GSNO and SPER-NO. These signals were not modified under N2 atmosphere, indicating that they are not a consequence to the effect of NOx species on complex III area. These results show that NO interacts with ubiquinone-cytochrome b area producing antimycin-like effects. This behaviour comprises the inhibition of electron transfer, the interruption of the oxidation of cytochromes b, and the enhancement of [UQH(•)]ss which, in turn, leads to an increase in O2(•-) and H2O2 mitochondrial production rates. PMID:26456055

  6. Differential efficacy of inhibition of mitochondrial and bacterial cytochrome bc1 complexes by center N inhibitors antimycin, ilicicolin H and funiculosin

    OpenAIRE

    Rotsaert, Frederik A. J.; Ding, Martina G.; Trumpower, Bernard L.

    2007-01-01

    We have compared the efficacy of inhibition of the cytochrome bc1 complexes from yeast and bovine heart mitochondria and Paracoccus denitrificans by antimycin, ilicicolin H, and funiculosin, three inhibitors that act at the quinone reduction site at center N of the enzyme. Although the three inhibitors have some structural features in common, they differ significantly in their patterns of inhibition. Also, while the overall folding pattern of cytochrome b around center N is similar in the enz...

  7. Genome Sequence of Streptomyces wadayamensis Strain A23, an Endophytic Actinobacterium from Citrus reticulata

    OpenAIRE

    de Oliveira, Luciana G; Tormet Gonzalez, Gabriela D.; Samborsky, Markyian; Marcon, Joelma; Araujo, Welington L.; de Azevedo, João Lucio

    2014-01-01

    The actinobacterium Streptomyces wadayamensis A23 is an endophyte of Citrus reticulata that produces the antimycin and mannopeptimycin antibiotics, among others. The strain has the capability to inhibit Xylella fastidiosa growth. The draft genome of S. wadayamensis A23 has ~7.0 Mb and 6,006 protein-coding sequences, with a 73.5% G+C content.

  8. Metabolomic Profiling and Genomic Study of a Marine Sponge-Associated Streptomyces sp.

    Directory of Open Access Journals (Sweden)

    Christina Viegelmann

    2014-06-01

    Full Text Available Metabolomics and genomics are two complementary platforms for analyzing an organism as they provide information on the phenotype and genotype, respectively. These two techniques were applied in the dereplication and identification of bioactive compounds from a Streptomyces sp. (SM8 isolated from the sponge Haliclona simulans from Irish waters. Streptomyces strain SM8 extracts showed antibacterial and antifungal activity. NMR analysis of the active fractions proved that hydroxylated saturated fatty acids were the major components present in the antibacterial fractions. Antimycin compounds were initially putatively identified in the antifungal fractions using LC-Orbitrap. Their presence was later confirmed by comparison to a standard. Genomic analysis of Streptomyces sp. SM8 revealed the presence of multiple secondary metabolism gene clusters, including a gene cluster for the biosynthesis of the antifungal antimycin family of compounds. The antimycin gene cluster of Streptomyces sp. SM8 was inactivated by disruption of the antimycin biosynthesis gene antC. Extracts from this mutant strain showed loss of antimycin production and significantly less antifungal activity than the wild-type strain. Three butenolides, 4,10-dihydroxy-10-methyl-dodec-2-en-1,4-olide (1, 4,11-dihydroxy-10-methyl-dodec-2-en-1,4-olide (2, and 4-hydroxy-10-methyl-11-oxo-dodec-2-en-1,4-olide (3 that had previously been reported from marine Streptomyces species were also isolated from SM8. Comparison of the extracts of Streptomyces strain SM8 and its host sponge, H. simulans, using LC-Orbitrap revealed the presence of metabolites common to both extracts, providing direct evidence linking sponge metabolites to a specific microbial symbiont.

  9. Genome Sequence of Streptomyces wadayamensis Strain A23, an Endophytic Actinobacterium from Citrus reticulata.

    Science.gov (United States)

    de Oliveira, Luciana G; Tormet Gonzalez, Gabriela D; Samborsky, Markyian; Marcon, Joelma; Araujo, Welington L; de Azevedo, João Lucio

    2014-01-01

    The actinobacterium Streptomyces wadayamensis A23 is an endophyte of Citrus reticulata that produces the antimycin and mannopeptimycin antibiotics, among others. The strain has the capability to inhibit Xylella fastidiosa growth. The draft genome of S. wadayamensis A23 has ~7.0 Mb and 6,006 protein-coding sequences, with a 73.5% G+C content. PMID:24994795

  10. ATP synthesis during exogenous NADH oxidation. A reappraisal.

    Science.gov (United States)

    Bernardi, P; Azzone, G F

    1982-01-20

    This paper reports a reinvestigation on the pathway for mitochondrial oxidation of exogenous NADH and on the related ATP synthesis, first reported 30 years ago (Lehninger, A.L. (1951) J. Biol. Chem. 190, 345-359). NADH oxidation, both in intact and in water-treated mitochondria, is 90% inhibited by mersalyl, an inhibitor of the outer membrane NADH-cytochrome b5 reductase, and 10% inhibited by rotenone. The mersalyl-sensitive, but not the rotenone-sensitive, portion of NADH oxidation is stimulated by exogenous cytochrome c. Part of ATP synthesis is independent of exogenous NADH and cytochrome c, and is inhibited by rotenone and antimycin A, and is therefore due to oxidation of endogenous substrates. Another part of ATP synthesis is dependent on exogenous NADH and cytochrome c, is insensitive to rotenone and antimycin A, and is due to operation of cytochrome oxidase. It is concluded that (i) oxidation of exogenous NADH in the presence of cytochrome c proceeds mostly through NADH-cytochrome b5 reductase and cytochrome b5 on the outer membrane and then through cytochrome oxidase via the cytochrome c shuttle, and (ii) ATP synthesis during oxidation of exogenous NADH is partly due to oxidation of endogenous substrates and partly to operation of cytochrome oxidase receiving electrons from the outer membrane via cytochrome c. PMID:6275889

  11. Ascorbic acid is a key participant during the interactions between chloroplasts and mitochondria to optimize photosynthesis and protect against photoinhibition

    Indian Academy of Sciences (India)

    Saikrishna Talla; Khateef Riazunnisa; Lolla Padmavathi; Pidakala Rajsheel; Agepati S Raghavendra

    2011-03-01

    The possible role of L-ascorbate (AsA) as a biochemical signal during the interactions between photosynthesis and respiration was examined in leaf discs of Arabidopsis thaliana. AsA content was either decreased as in AsA-deficient vtc1 mutants or increased by treatment with L-galactono-1, 4-lactone (L-GalL, a precursor of AsA; EC 1.3.2.3). In mutants, photosynthesis was extremely sensitive to both antimycin A (inhibitor of the cytochrome oxidase pathway [COX pathway]) and salicylhydroxamic acid (SHAM, inhibitor of the alternative pathway [AOX pathway]), particularly at high light conditions. Mitochondrial inhibitors lowered the ratio of reduced AsA to total AsA, at high light, indicating oxidative stress in leaf discs. Elevation of AsA by L-GalL decreased the sensitivity of photosynthesis at high light to antimycin A or SHAM, sustained photosynthesis at supraoptimal light and relieved the extent of photoinhibition. High ratios of reduced AsA to total AsA in L-GalL-treated leaf discs suggests that L-GalL lowers oxidative stress. The protection by L-GalL of photosynthesis against the mitochondrial inhibitors and photoinhibition was quite pronounced in vtc1 mutants. Our results suggest that the levels and redox state of AsA modify the pattern of modulation of photosynthesis by mitochondrial metabolism. The extent of the AOX pathway as a percentage of the total respiration in Arabidopsis mesophyll protoplasts was much higher in vtc1 than in wild type. We suggest that the role of AsA becomes pronounced at high light and/or when the AOX pathway is inhibited. While acknowledging the importance of the COX pathway, we hypothesize that AsA and the AOX pathway may complement each other to protect photosynthesis against photoinhibition.

  12. Mass spectrometric determination of O2 gas exchange during a dark-to-light transition in higher-plant cells : Evidence for two individual O2-uptake components.

    Science.gov (United States)

    Avelange, M H; Rébeillé, F

    1991-01-01

    The exchange of O2 and CO2 by photoautotrophic cells of Euphorbia characias L. was measured using a mass-spectrometry technique. During a dark-tolight transition the O2 uptake rate was little affected whereas CO2 efflux was decreased by 40%. In order to differentiate eventual superimposed O2-uptake processes, the kinetics of O2 exchange resulting from brief illuminations were measured with a highly sensitive device. When the cells were exposed to a saturating light for short periods, the rate of O2 uptake passed through a series of transients: there was first a stimulation occurring 2-3 s after the appearance of O2 from water-splitting, followed 30 s later by an inhibition. These two transients were reduced 80% by 3-(3',4'-dichlorophenyl)1, 1-dimethylurea (DCMU), indicating that they relied on the linear transport of electrons in the chloroplasts. The first transient (stimulation of an O2 uptake) was little affected by mitochondrial inhibitors such as antimycin A and oligomycin or the uncoupler carbonylcyanide m-chlorophenylhydrazone (CCCP) but was increased in presence of KCN. When spaced flashes (2 us duration; 100-ms intervals) were used instead of continuous light, this transient was almost suppressed indicating that it was dependent on the saturation of some component of the chloroplastic chain. The second transient (inhibition of O2 uptake) was present when spaced flashes were used instead of continuous light. It was markedly decreased by addition of CCCP and mitochondrial inhibitors (antimycin A, oligomycin, KCN) which strongly indicates that it relied on mitochondrial respiration. It is concluded from these experiments that illumination of the cells resulted in an inhibition of mitochondrial respiration, but the resulting inhibition of O2 uptake was hidden by the appearance of an O2-uptake process of extramitochondrial origin, presumably located in the chloroplast. PMID:24193615

  13. A broad distribution of the alternative oxidase in microsporidian parasites.

    Directory of Open Access Journals (Sweden)

    Bryony A P Williams

    2010-02-01

    Full Text Available Microsporidia are a group of obligate intracellular parasitic eukaryotes that were considered to be amitochondriate until the recent discovery of highly reduced mitochondrial organelles called mitosomes. Analysis of the complete genome of Encephalitozoon cuniculi revealed a highly reduced set of proteins in the organelle, mostly related to the assembly of iron-sulphur clusters. Oxidative phosphorylation and the Krebs cycle proteins were absent, in keeping with the notion that the microsporidia and their mitosomes are anaerobic, as is the case for other mitosome bearing eukaryotes, such as Giardia. Here we provide evidence opening the possibility that mitosomes in a number of microsporidian lineages are not completely anaerobic. Specifically, we have identified and characterized a gene encoding the alternative oxidase (AOX, a typically mitochondrial terminal oxidase in eukaryotes, in the genomes of several distantly related microsporidian species, even though this gene is absent from the complete genome of E. cuniculi. In order to confirm that these genes encode functional proteins, AOX genes from both A. locustae and T. hominis were over-expressed in E. coli and AOX activity measured spectrophotometrically using ubiquinol-1 (UQ-1 as substrate. Both A. locustae and T. hominis AOX proteins reduced UQ-1 in a cyanide and antimycin-resistant manner that was sensitive to ascofuranone, a potent inhibitor of the trypanosomal AOX. The physiological role of AOX microsporidia may be to reoxidise reducing equivalents produced by glycolysis, in a manner comparable to that observed in trypanosomes.

  14. The energy-conserving nitric-oxide-reductase system in Paracoccus denitrificans. Distinction from the nitrite reductase that catalyses synthesis of nitric oxide and evidence from trapping experiments for nitric oxide as a free intermediate during denitrification.

    Science.gov (United States)

    Carr, G J; Page, M D; Ferguson, S J

    1989-02-15

    1. A Clark-type electrode that responds to nitric oxide has been used to show that cytoplasmic membrane vesicles of Paracoccus denitrificans have a nitric-oxide reductase activity. Nitrous oxide is the reaction product. NADH, succinate or isoascorbate plus 2,3,5,6-tetramethyl-1,4-phenylene diamine can act as reductants. The NADH-dependent activity is resistant to freezing of the vesicles and thus the NADH:nitric-oxide oxidoreductase activity of stored frozen vesicles provides a method for calibrating the electrode by titration of dissolved nitric oxide with NADH. The periplasmic nitrite reductase and nitrous-oxide reductase enzymes are absent from the vesicles which indicates that nitric-oxide reductase is a discrete enzyme associated with the denitrification process. This conclusion was supported by the finding that nitric-oxide reductase activity was absent from both membranes prepared from aerobically grown P. denitrificans and bovine heart submitochondrial particles. 2. The NADH: nitric-oxide oxidoreductase activity was inhibited by concentrations of antimycin or myxothiazol that were just sufficient to inhibit the cytochrome bc1 complex of the ubiquinol--cytochrome-c oxidoreductase. The activity was deduced to be proton translocating by the observations of: (a) up to 3.5-fold stimulation upon addition of an uncoupler; and (b) ATP synthesis with a P:2e ratio of 0.75. 3. Nitrite reductase of cytochrome cd1 type was highly purified from P. denitrificans in a new, high-yield, rapid two- or three-step procedure. This enzyme catalysed stoichiometric synthesis of nitric oxide. This observation, taken together with the finding that the maximum rate of NADH:nitric-oxide oxidoreductase activity catalysed by the vesicles was comparable with that of NADH:nitrate-oxidoreductase, is consistent with a role for nitric-oxide reductase in the physiological conversion of nitrate or nitrite to dinitrogen gas. 4. Intact cells of P. denitrificans also reduced nitric oxide in an

  15. Storage of biogenic amines in intact blood platelets of man. Dependence on a proton gradient

    International Nuclear Information System (INIS)

    The actions of ionophores with different ion specificities and of thrombin on the release of 14C-labeled 5-hydroxytryptamine, [3H]noradrenaline, and endogenous ATP were measured in human platelets suspended in media with various K+ and Na+ concentrations. Besides thrombin, those ionophores [monensin, nigericin, and the combination of carbonylcyanide-p-trifluoromethoxyphenyl hydrazone (FCCP) with nonactin and/or valinomycin] which cause a rapid collapse of H+ gradients induced a fast and virtually total release of 14C-labeled 5-hydroxytryptamine and [3H]noradrenaline into the various media. FCCP alone, which causes an inversion of the membrane potential to inside negative values, induced a considerably slower amine release. Changes in the K+ and Na+ gradients did not lead to amine release, nor did interference with energy transduction by antimycin A with or without glycolysis inhibitors. Monensin and FCCP did not release ATP, whereas thrombin, added before or after incubation of platelets with FCCP and monensin, caused a marked liberation of the nucleotide. It is concluded that in intact human platelets (a) the intragranular storage of 5-hydroxytryptamine and noradrenaline mainly depends on the proton gradient across the granular membrane, and (b) ionophores causing a collapse of H+ gradients induce non-exocytotic release of 5-hydroxytryptamine and noradrenaline from intracellular storage granules

  16. Existence of aa3-type ubiquinol oxidase as a terminal oxidase in sulfite oxidation of Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Sugio, Tsuyoshi; Hisazumi, Tomohiro; Kanao, Tadayoshi; Kamimura, Kazuo; Takeuchi, Fumiaki; Negishi, Atsunori

    2006-07-01

    It was found that Acidithiobacillus thiooxidans has sulfite:ubiquinone oxidoreductase and ubiquinol oxidase activities in the cells. Ubiquinol oxidase was purified from plasma membranes of strain NB1-3 in a nearly homogeneous state. A purified enzyme showed absorption peaks at 419 and 595 nm in the oxidized form and at 442 and 605 nm in the reduced form. Pyridine ferrohaemochrome prepared from the enzyme showed an alpha-peak characteristic of haem a at 587 nm, indicating that the enzyme contains haem a as a component. The CO difference spectrum of ubiquinol oxidase showed two peaks at 428 nm and 595 nm, and a trough at 446 nm, suggesting the existence of an aa(3)-type cytochrome in the enzyme. Ubiquinol oxidase was composed of three subunits with apparent molecular masses of 57 kDa, 34 kDa, and 23 kDa. The optimum pH and temperature for ubiquinol oxidation were pH 6.0 and 30 degrees C. The activity was completely inhibited by sodium cyanide at 1.0 mM. In contrast, the activity was inhibited weakly by antimycin A(1) and myxothiazol, which are inhibitors of mitochondrial bc(1) complex. Quinone analog 2-heptyl-4-hydoroxyquinoline N-oxide (HOQNO) strongly inhibited ubiquinol oxidase activity. Nickel and tungstate (0.1 mM), which are used as a bacteriostatic agent for A. thiooxidans-dependent concrete corrosion, inhibited ubiquinol oxidase activity 100 and 70% respectively. PMID:16861791

  17. Lacidipine Attenuates Apoptosis via a Caspase-3 Dependent Pathway in Human Kidney Cells

    Directory of Open Access Journals (Sweden)

    Aiqi Zhang

    2013-10-01

    Full Text Available Background: Acute kidney injury (AKI is common in hospitalised patients and has a poor prognosis. Therefore, new therapeutic strategies are anticipated. Lacidipine, a novel third-generation dihydropyridine calcium channel blocker, has been demonstrated effective for hypertension. However, its potential effect on renal injury remains unknown. In the present study, an in vitro model of renal ischemia reperfusion (I/R injury was used to investigate the protective effect and underlying mechanisms of lacidipine on human kidney cell (HKC apoptosis. Methods: HKCs were subjected to adenosine triphosphate (ATP depletion and recovery (0.01 µM AA, depletion for 2 h and recovery for 30 min, with or without lacidipine (1 µM and 10 µM, 24 h, then cell viability and apoptosis were determined using the cell counting kit-8 (CCK-8 assay and Annexin V flow cytometry. The expression of Bcl-2, Bax, and cytochrome c (cyt c was examined by western blot. Results: Antimycin A (AA was found to induce apoptosis of HKCs. The proportion of early apoptosis and activity of caspase-3 peaked at 30 min after ATP depletion and recovery and were attenuated by lacidipine. The expression of cyt c and Bax was decreased, while that of Bcl-2 was increased significantly in lacidipine treated group. Conclusion: We conclude that lacidipine protects HKCs against apoptosis induced by ATP depletion and recovery by regulating the caspase-3 pathway.

  18. In situ quantification of mitochondrial respiration in permeabilized fibers of a marine invertebrate with low aerobic capacity.

    Science.gov (United States)

    Pichaud, Nicolas; Rioux, Pierre; Blier, Pierre U

    2012-04-01

    The aim of this study was to design a protocol to allow the assessment of normal and alternative pathways for electron transport in mitochondria using an in situ approach (on permeabilized fibers) in high-resolution respirometry. We measured the oxygen consumption of permeabilized fibers from Nereis (Neanthes) virens with different substrates and the presence of ADP. To estimate the alternative oxidase (AOX) activity, antimycin A was introduced in order to inhibit complex III. Moreover, the apparent complex IV (COX) excess capacity was evaluated using different substrates to assess the implication of this complex in the partitioning of electrons during its progressive inhibition. Our in situ method enabled to quantify the activity of the normal COX pathway as well as the AOX pathway when different substrates were oxidized by either complex I, complex II or both. Using this approach, we confirmed that according to the substrates used, each pathway has a different role and consequently is otherwise involved in the partitioning of electrons through the electron transport system, and suggested that the AOX activity is triggered not only by the redox state of the cell but also by the type of substrates provided to mitochondria. PMID:22244894

  19. Energy metabolism in rat mast cells in relation to histamine secretion

    DEFF Research Database (Denmark)

    Johansen, T

    1987-01-01

    of histamine was induced by the antigen-antibody reaction, the polymeric amine compound 48/80, and the divalent ionophore A23187. 2. In presence of low concentrations of metabolic inhibitors (oligomycin or antimycin A) a linear relation between the secretion of histamine induced by all three liberators...

  20. Ethacrynic acid inhibition of histamine release from rat mast cells: effect on cellular ATP levels and thiol groups

    DEFF Research Database (Denmark)

    Johansen, Torben

    1983-01-01

    The experiments concerned the effect of ethacrynic acid (0.5 mM) on the adenosine triphosphate (ATP) content of rat mast cells and the effect on histamine release induced by the ionophore A23187 (10 microM). Ethacrynic acid decreased the ATP level of the cells in presence of antimycin A and glucose...

  1. A novel high-throughput assay for islet respiration reveals uncoupling of rodent and human islets.

    Directory of Open Access Journals (Sweden)

    Jakob D Wikstrom

    Full Text Available BACKGROUND: The pancreatic beta cell is unique in its response to nutrient by increased fuel oxidation. Recent studies have demonstrated that oxygen consumption rate (OCR may be a valuable predictor of islet quality and long term nutrient responsiveness. To date, high-throughput and user-friendly assays for islet respiration are lacking. The aim of this study was to develop such an assay and to examine bioenergetic efficiency of rodent and human islets. METHODOLOGY/PRINCIPAL FINDINGS: The XF24 respirometer platform was adapted to islets by the development of a 24-well plate specifically designed to confine islets. The islet plate generated data with low inter-well variability and enabled stable measurement of oxygen consumption for hours. The F1F0 ATP synthase blocker oligomycin was used to assess uncoupling while rotenone together with myxothiazol/antimycin was used to measure the level of non-mitochondrial respiration. The use of oligomycin in islets was validated by reversing its effect in the presence of the uncoupler FCCP. Respiratory leak averaged to 59% and 49% of basal OCR in islets from C57Bl6/J and FVB/N mice, respectively. In comparison, respiratory leak of INS-1 cells and C2C12 myotubes was measured to 38% and 23% respectively. Islets from a cohort of human donors showed a respiratory leak of 38%, significantly lower than mouse islets. CONCLUSIONS/SIGNIFICANCE: The assay for islet respiration presented here provides a novel tool that can be used to study islet mitochondrial function in a relatively high-throughput manner. The data obtained in this study shows that rodent islets are less bioenergetically efficient than human islets as well as INS1 cells.

  2. Dependence of anaphylactic histamine release from rat mast cells on cellular energy metabolism

    DEFF Research Database (Denmark)

    Johansen, Torben

    1981-01-01

    The relation between anaphylactic histamine release and the adenosine triphosphate (ATP) content of the mast cells was studied. The cells were incubated with glycolytic (2-deoxyglucose) and respiratory inhibitors (antimycin A and oligomycin) in order to decrease the ATP content of the cells prior...

  3. Increased Na+/K(+)-pump activity and adenosine triphosphate utilization after compound 48/80-induced histamine secretion from rat mast cells

    DEFF Research Database (Denmark)

    Johansen, Torben; Praetorius, Birger Hans

    1994-01-01

    -production were measured by the bioluminescence technique (firefly lantern) and by measurement of the lactate production under anaerobic conditions (antimycin A, oligomycin), respectively. There was an increased requirement for ATP after the secretory response associated with an increased activity of the Na...

  4. Estimation of the rate of energy production of rat mast cells in vitro

    DEFF Research Database (Denmark)

    Johansen, Torben

    1983-01-01

    Rat mast cells were treated with glycolytic and respiratory inhibitors. The rate of adenosine triphosphate depletion of cells incubated with both types of inhibitors and the rate of lactate produced in presence of antimycin A and glucose were used to estimate the rate of oxidative and glycolytic...

  5. A functional BH3 domain in an aquaporin from Leishmania infantum.

    Science.gov (United States)

    Genes, C M; de Lucio, H; González, V M; Sánchez-Murcia, P A; Rico, E; Gago, F; Fasel, N; Jiménez-Ruiz, A

    2016-01-01

    Despite the absence of sequences showing significant similarity to any of the members of the Bcl-2 family of proteins in protozoa, experiments carried out in yeast or trypanosomatids have demonstrated that ectopic expression of some of these members alters their response to different death stimuli. Because the BH3 domain is the smallest common signature in all the proteins of this family of apoptosis regulators and also because they are essential for molecular interactions between antagonistic members, we looked for sequences with significant similarity to the BH3 motif in the Leishmania infantum genome. Among the top scoring ones, we found the MYLALQNLGDEV amino-acid stretch at the C terminus of a previously described aquaporin, now renamed as Li-BH3AQP. This motif is highly conserved in homologous proteins from other species of the Leishmania genus. The association of Li-BH3AQP with human Bcl-XL was demonstrated by both co-immunoprecipitation and yeast two-hybrid experiments. Ectopic expression of Li-BH3AQP reduced viability of HeLa cells and this deleterious effect was abrogated by the simultaneous overexpression of Bcl-XL. Although we were not able to demonstrate a reduction in parasite viability when the protein was overexpressed in Leishmania promastigotes, a prodeath effect could be observed when the parasites overexpressing Li-BH3AQP were treated with staurosporine or antimycin A. Surprisingly, these parasites were more resistant, compared with wild-type parasites, to hypotonic stress or nutrient deprivation. The prodeath activity was abolished upon replacement of two highly conserved amino acids in this BH3 domain. Taken together, these results point to Li-BH3AQP as the first non-enzymatic protein ever described in trypanosomatids that is involved in cell death. PMID:27551533

  6. Mitochondrial function is involved in regulation of cholesterol efflux to apolipoprotein (apoA-I from murine RAW 264.7 macrophages

    Directory of Open Access Journals (Sweden)

    Allen Anne Marie

    2012-12-01

    Full Text Available Abstract Background Mitochondrial DNA damage, increased production of reactive oxygen species and progressive respiratory chain dysfunction, together with increased deposition of cholesterol and cholesteryl esters, are hallmarks of atherosclerosis. This study investigated the role of mitochondrial function in regulation of macrophage cholesterol efflux to apolipoprotein A-I, by the addition of established pharmacological modulators of mitochondrial function. Methods Murine RAW 264.7 macrophages were treated with a range of concentrations of resveratrol, antimycin, dinitrophenol, nigericin and oligomycin, and changes in viability, cytotoxicity, membrane potential and ATP, compared with efflux of [3H]cholesterol to apolipoprotein (apo A-I. The effect of oligomycin treatment on expression of genes implicated in macrophage cholesterol homeostasis were determined by quantitative polymerase chain reaction, and immunoblotting, relative to the housekeeping enzyme, Gapdh, and combined with studies of this molecule on cholesterol esterification, de novo lipid biosynthesis, and induction of apoptosis. Significant differences were determined using analysis of variance, and Dunnett’s or Bonferroni post t-tests, as appropriate. Results The positive control, resveratrol (24 h, significantly enhanced cholesterol efflux to apoA-I at concentrations ≥30 μM. By contrast, cholesterol efflux to apoA-I was significantly inhibited by nigericin (45%; ppAbca1 mRNA. Oligomycin treatment did not affect cholesterol biosynthesis, but significantly inhibited cholesterol esterification following exposure to acetylated LDL, and induced apoptosis at ≥30 μM. Finally, oligomycin induced the expression of genes implicated in both cholesterol efflux (Abca1, Abcg4, Stard1 and cholesterol biosynthesis (Hmgr, Mvk, Scap, Srebf2, indicating profound dysregulation of cholesterol homeostasis. Conclusions Acute loss of mitochondrial function, and in particular Δψm, reduces

  7. Characterization of the respiratory chain of Helicobacter pylori

    DEFF Research Database (Denmark)

    Chen, M; Andersen, L P; Zhai, L; Kharazmi, A

    1999-01-01

    The respiratory chain of Helicobacter pylori has been investigated. The total insensitivity of activities of NADH dehydrogenase to rotenone and of NADH-cytochrome c reductase to antimycin is indicative of the absence of the classical complex I of the electron transfer chain in this bacterium. NADPH......-dependent respiration was significantly stronger than NADH-dependent respiration, indicating that this is a major respiratory electron donor in H. pylori. Fumarate and malonate exhibited a concentration-dependent inhibitory effect on the activity of succinate dehydrogenase. The activity of succinate-cytochrome c...... reductase was inhibited by antimycin, implying the presence of a classical pathway from complex II to complex III in this bacterium. The presence of NADH-fumarate reductase (FRD) was demonstrated in H. pylori and fumarate could reduce H2O2 production from NADH, indicating fumarate to be an endogenous...

  8. Adhesion of Colletotrichum lindemuthianum Spores to Phaseolus vulgaris Hypocotyls and to Polystyrene

    OpenAIRE

    Young, David H.; Kauss, Heinrich

    1984-01-01

    Adhesion of Colletotrichum lindemuthianum spores to Phaseolus vulgaris hypocotyls and to polystyrene was inhibited by the respiratory inhibitors sodium azide and antimycin A, indicating a requirement for metabolic activity in adhesion. Various commercial proteins and Tween 80 also reduced adhesion to both surfaces. Binding was enhanced by the presence of salts: sodium, potassium, calcium, and magnesium chlorides were equally effective. The removal of surface wax from hypocotyls by chloroform ...

  9. Alpha7 nicotinic receptor activation protects against oxidative stress via heme-oxygenase I induction.

    Science.gov (United States)

    Navarro, Elisa; Buendia, Izaskun; Parada, Esther; León, Rafael; Jansen-Duerr, Pidder; Pircher, Haymo; Egea, Javier; Lopez, Manuela G

    2015-10-15

    Subchronic oxidative stress and inflammation are being increasingly implicated in the pathogenesis of numerous diseases, such as Alzheimer's or Parkinson's disease. This study was designed to evaluate the potential protective role of α7 nicotinic receptor activation in an in vitro model of neurodegeneration based on subchronic oxidative stress. Rat organotypic hippocampal cultures (OHCs) were exposed for 4 days to low concentration of lipopolysaccharide (LPS) and the complex III mitochondrial blocker, antimycin-A. Antimycin-A (0.1μM) and lipopolysaccharide (1ng/ml) caused low neurotoxicity on their own, measured as propidium iodide fluorescence in CA1 and CA3 regions. However, their combination (LPS/AA) caused a greater detrimental effect, in addition to mitochondrial depolarization, overproduction of reactive oxygen species (ROS) and Nox4 overexpression. Antimycin-A per se increased ROS and mitochondrial depolarization, although these effects were significantly higher when combined with LPS. More interesting was the finding that exposure of OHCs to the combination of LPS/AA triggered aberrant protein aggregation, measured as thioflavin S immunofluorescence. The α7 nicotinic receptor agonist, PNU282987, prevented the neurotoxicity and the pathological hallmarks observed in the LPS/AA subchronic toxicity model (oxidative stress and protein aggregates); these effects were blocked by α-bungarotoxin and tin protoporphyrin, indicating the participation of α7 nAChRs and heme-oxygenase I induction. In conclusion, subchronic exposure of OHCs to low concentration of antimycin-A plus LPS reproduced pathological features of neurodegenerative disorders. α7 nAChR activation ameliorated these alterations by a mechanism involving heme-oxygenase I induction. PMID:26212551

  10. Pharmacological Modulation of the Mitochondrial Electron Transport Chain in Paclitaxel-Induced Painful Peripheral Neuropathy

    OpenAIRE

    Griffiths, Lisa A.; Flatters, Sarah J. L.

    2015-01-01

    Paclitaxel is an effective first-line chemotherapeutic with the major dose-limiting side effect of painful neuropathy. Mitochondrial dysfunction and oxidative stress have been implicated in paclitaxel-induced painful neuropathy. Here we show the effects of pharmacological modulation of mitochondrial sites that produce reactive oxygen species using systemic rotenone (complex I inhibitor) or antimycin A (complex III inhibitor) on the maintenance and development of paclitaxel-induced mechanical ...

  11. The Neuroprotective Effects of Carnosine in Early Stage of Focal Ischemia Rodent Model

    OpenAIRE

    Park, Hui-Seung; Han, Kyung-Hoon; Shin, Jeoung-A; Park, Joo-Hyun; Song, Kwan-Young; Kim, Doh-Hee

    2014-01-01

    Objective This study was conducted to elucidate neuroprotective effect of carnosine in early stage of stroke. Methods Early stage of rodent stroke model and neuroblastoma chemical hypoxia model was established by middle cerebral artery occlusion and antimycin A. Neuroprotective effect of carnosine was investigated with 100, 250, and 500 mg of carnosine treatment. And antioxidant expression was analyzed by enzyme linked immunosorbent assay (ELISA) and western blot in brain and blood. Results I...

  12. Differential labeling of the subunits of respiratory complex III with [3H]succinic anhydride, [14C]succinic anhydride, and p-diazobenzene-[35S]sulfonate

    International Nuclear Information System (INIS)

    Exposure of antimycin-treated Complex III (ubiquinol-cytochrome c reductase) purified from bovine heart mitochondria to [3H]succinic anhydride plus [35S]p-diazobenzenesulfonate (DABS) resulted in somewhat uniform relative labeling of the eight measured subunits of the complex by [3H]succinic anhydride. In contrast, relative labeling by [35S]DABS was similar to [3H]succinic anhydride for the subunits of high molecular mass, i.e., core proteins, cytochromes, and the iron-sulfur protein, but greatly reduced for the polypeptides of molecular mass below 15 kDa. With Complex II depleted in the iron-sulfur protein the relative labeling of core protein I by exposure of the complex to [3H]succinic anhydride was significantly enhanced, whereas labeling of the polypeptides represented by SDS-PAGE bands 7 and 8 was significantly inhibited. Dual labeling of the subunits of Complex III by 14C- and 3H-labeled succinic anhydride before and after dissociation of the complex by sodium dodecyl sulfate, respectively, was measured with the complex in its oxidized, reduced, and antimycin-inhibited states. Subunits observed to be most accessible or reactive to succinic anhydride were core protein II, the iron-sulfur protein, and polypeptides of SDS-PAGE bands 7,8, and 9. Two additional polypeptides of molecular masses 23 and 12kDa, not normally resolved by gel-electrophoresis, were detected. Reduction of the complex resulted in a significant change of 14C/3H labeling ratio of core protein only, whereas treatment of the complex with antimycin resulted in decreases in 14C/3H labeling ratios of core proteins I and II, cytochrome c1, and a polypeptide of molecular mass 13kDa identified as an antimycin-binding protein

  13. Ubisemiquinone is the electron donor for superoxide formation by complex III of heart mitochondria.

    Science.gov (United States)

    Turrens, J F; Alexandre, A; Lehninger, A L

    1985-03-01

    Much evidence indicates that superoxide is generated from O2 in a cyanide-sensitive reaction involving a reduced component of complex III of the mitochondrial respiratory chain, particularly when antimycin A is present. Although it is generally believed that ubisemiquinone is the electron donor to O2, little experimental evidence supporting this view has been reported. Experiments with succinate as electron donor in the presence of antimycin A in intact rat heart mitochondria, which contain much superoxide dismutase but little catalase, showed that myxothiazol, which inhibits reduction of the Rieske iron-sulfur center, prevented formation of hydrogen peroxide, determined spectrophotometrically as the H2O2-peroxidase complex. Similarly, depletion of the mitochondria of their cytochrome c also inhibited formation of H2O2, which was restored by addition of cytochrome c. These observations indicate that factors preventing the formation of ubisemiquinone also prevent H2O2 formation. They also exclude ubiquinol, which remains reduced under these conditions, as the reductant of O2. Since cytochrome b also remains fully reduced when myxothiazol is added to succinate- and antimycin A-supplemented mitochondria, reduced cytochrome b may also be excluded as the reductant of O2. These observations, which are consistent with the Q-cycle reactions, by exclusion of other possibilities leave ubisemiquinone as the only reduced electron carrier in complex III capable of reducing O2 to O2-. PMID:2983613

  14. Oxygen, pHi and arrest of biosynthesis in brine shrimp embryos.

    Science.gov (United States)

    Hand, S C

    1997-12-01

    Embryos of the brine shrimp Artemia franciscana are able to withstand bouts of environmental anoxia for several years by entering a quiescent state, during which time metabolism is greatly depressed. Within minutes of oxygen removal, intracellular pH (pHi) drops at least 1.0 unit. This acidification has been strongly implicated in the arrest of both catabolic and anabolic processes in the cytoplasm. A global arrest of cytoplasmic translation accompanies the transition into anoxia or into aerobic acidosis (artificial quiescence imposed by intracellular acidification with CO2 in the presence of oxygen). Similarly, protein synthesis in isolated mitochondria from these embryos is also reduced markedly in response to acidic pH (80% reduction) or anoxia (79% reduction). The constancy of mRNA levels during quiescence indicates that protein synthesis is likely to be controlled at the translational level. Mitochondrial matrix pH is 8.2 during protein synthesis assays performed at the extramitochondrial pH optimum of 7.5. When this proton gradient is abolished with the K+/H+ ionophore nigericin, the extramitochondrial pH optimum for protein synthesis displays an alkaline shift of approximately 0.7 pH unit. These data suggest the presence of proton-sensitive translational components within the mitochondrion. The oxygen dependency of mitochondrial protein synthesis is not explained simply by blockage of the electron transport chain or by the increased redox state. Whereas oxygen deprivation substantially depresses protein synthesis by 77% after 1 h, normoxic incubations with saturating concentrations of cyanide or antimycin A have only a modest effect (36% reduction, cyanide; 20%, antimycin A). This cyanide- and antimycin-insensitive, but hypoxia-sensitive, inhibitory signature for the arrest of protein synthesis suggests the presence of a molecular oxygen sensor within the mitochondrion. PMID:9429663

  15. Roles for Nox4 in the contractile response of bovine pulmonary arteries to hypoxia

    OpenAIRE

    Ahmad, Mansoor; Kelly, Melissa R.; Zhao, Xiangmin; Kandhi, Sharath; Wolin, Michael S.

    2010-01-01

    Hypoxia appears to promote contraction [hypoxic pulmonary vasoconstriction (HPV)] of bovine pulmonary arteries (BPA) through removal of a peroxide-mediated relaxation. This study examines the roles of BPA Nox oxidases and mitochondria in the HPV response. Inhibitors of Nox2 (0.1 mM apocynin and 50 μM gp91-dstat) and mitochondrial electron transport (10 μM antimycin and rotenone) decreased superoxide generation in BPA without affecting contraction to 25 mM KCl or the HPV response. Transfection...

  16. Electron transport chain inhibitors induce microglia activation through enhancing mitochondrial reactive oxygen species production.

    Science.gov (United States)

    Ye, Junli; Jiang, Zhongxin; Chen, Xuehong; Liu, Mengyang; Li, Jing; Liu, Na

    2016-01-15

    Reactive oxygen species (ROS) are believed to be mediators of excessive microglial activation, yet the resources and mechanism are not fully understood. Here we stimulated murine microglial BV-2 cells and primary microglial cells with different inhibitors of electron transport chain (ETC), rotenone, thenoyltrifluoroacetone (TTFA), antimycin A, and NaN3 to induce mitochondrial ROS production and we observed the role of mitochondrial ROS in microglial activation. Our results showed that ETC inhibitors resulted in significant changes in cell viability, microglial morphology, cell cycle arrest and mitochondrial ROS production in a dose-dependent manner in both primary cultural microglia and BV-2 cell lines. Moreover, ETC inhibitors, especially rotenone and antimycin A stimulated secretion of interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 12 (IL-12) and tumor necrosis factor α (TNF-α) by microglia with marked activation of mitogen-activated proteinkinases (MAPKs) and nuclear factor κB (NF-κB), which could be blocked by specific inhibitors of MAPK and NF-κB and mitochondrial antioxidants, Mito-TEMPO. Taken together, our results demonstrated that inhibition of mitochondrial respiratory chain in microglia led to production of mitochondrial ROS and therefore may activate MAPK/NF-кB dependent inflammatory cytokines release in microglia, which indicated that mitochondrial-derived ROS were contributed to microglial activation. PMID:26511505

  17. Intracellular transport of secretory proteins in the pancreatic exocrine cell. IV. Metabolic requirements.

    Science.gov (United States)

    Jamieson, J D; Palade, G E

    1968-12-01

    Since in the pancreatic exocrine cell synthesis and intracellular transport of secretory proteins can be uncoupled (1), it is possible to examine separately the metabolic requirements of the latter process. To this intent, guinea pig pancreatic slices were pulse labeled with leucine-(3)H for 3 min and incubated post-pulse for 37 min in chase medium containing 5 x 10(-4)M cycloheximide and inhibitors of glycolysis, respiration, or oxidative phosphorylation. In each case, the effect on transport was assessed by measuring the amount of labeled secretory proteins found in zymogen granule fractions isolated from the corresponding slices. This assay is actually a measure of the efficiency of transport of secretory proteins from the cisternae of the rough endoplasmic reticulum (RER) to the condensing vacuoles of the Golgi complex which are recovered in the zymogen granule fraction (16). The results indicate that transport is insensitive to glycolytic inhibitors (fluoride, iodoacetate) but is blocked by respiratory inhibitors (N(2), cyanide, Antimycin A) and by inhibitors of oxidative phosphorylation (dinitrophenol, oligomycin). Except for Antimycin A, the effect is reversible. Parallel radioautographic studies and cell fractionation procedures applied to microsomal subfractions have indicated that the energy-dependent step is located between the transitional elements of the RER and the small, smooth-surfaced vesicles at the periphery of the Golgi complex. Radiorespirometric data indicate that the substrates oxidized to support transport are endogenous long-chain fatty acids. PMID:5699933

  18. Differential effects of buffer pH on Ca2+-induced ROS emission with inhibited mitochondrial complex I and III

    Directory of Open Access Journals (Sweden)

    Daniel P Lindsay

    2015-03-01

    Full Text Available Excessive mitochondrial reactive oxygen species (ROS emission is a critical component in the etiolo-gy of ischemic injury. Complex I and complex III of the electron transport chain are considered the primary sources of ROS emission during cardiac ischemia and reperfusion (IR injury. Several factors modulate ischemic ROS emission, such as an increase in extra-matrix Ca2+, a decrease in extra-matrix pH, and a change in substrate utilization. Here we examined the combined effects of these factors on ROS emission from respiratory complex I and III under conditions of simulated IR injury. Guinea pig heart mitochondria were suspended in experimental buffer at a given pH and incubated with or without CaCl2. Mitochondria were then treated with either pyruvate, a complex I substrate, followed by rote-none, a complex I inhibitor, or succinate, a complex II substrate, followed by antimycin A, a complex III inhibitor. H2O2 release rate and matrix volume were compared with and without adding CaCl2 and at pH 7.15, 6.9, or 6.5 with pyruvate + rotenone or succinate + antimycin A to simulate conditions that may occur during in vivo cardiac IR injury. We found a large increase in H2O2 release with high [CaCl2] and pyruvate + rotenone at pH 6.9, but not at pHs 7.15 or 6.5. Large increases in H2O2 release rate also occurred at each pH with high [CaCl2] and succinate + antimycin A, with the highest levels observed at pH 7.15. The increases in H2O2 release were associated with significant mitochondrial swelling, and both H2O2 release and swelling were abolished by cyclosporine A, a desensitizer of the mitochondrial permeability transition pore. These results indicate that ROS production by complex I and by III is differently affected by buffer pH and Ca2+ loading with mPTP opening. The study sug-gests that changes in the levels of cytosolic Ca2+ and pH during IR alter the relative amounts of ROS produced at mitochondrial respiratory complex I and complex III.

  19. Redox signaling in the growth and development of colonial hydroids.

    Science.gov (United States)

    Blackstone, Neil W

    2003-02-01

    Redox signaling provides a quick and efficient mechanism for clonal or colonial organisms to adapt their growth and development to aspects of the environment, e.g. the food supply. A 'signature' of mitochondrial redox signaling, particularly as mediated by reactive oxygen species (ROS), can be elucidated by experimental manipulation of the electron transport chain. The major sites of ROS formation are found at NADH dehydrogenase of complex I and at the interface between coenzyme Q and complex III. Inhibitors of complex III should thus upregulate ROS from both sites; inhibitors of complex I should upregulate ROS from the first but not the second site, while uncouplers of oxidative phosphorylation should downregulate ROS from both sites. To investigate the possibility of such redox signaling, perturbations of colony growth and development were carried out using the hydroid Podocoryna carnea. Oxygen uptake of colonies was measured to determine comparable physiological doses of antimycin A(1) (an inhibitor of complex III), rotenone (an inhibitor of complex I) and carbonyl cyanide m-chlorophenylhydrazone (CCCP; an uncoupler of oxidative phosphorylation). Using these doses, clear effects on colony growth and development were obtained. Treatment with antimycin A(1) results in 'runner-like' colony growth, with widely spaced polyps and stolon branches, while treatment with CCCP results in 'sheet-like' growth, with closely spaced polyps and stolon branches. Parallel results have been obtained previously with azide, an inhibitor of complex IV, and dinitrophenol, another uncoupler of oxidative phosphorylation. Perhaps surprisingly, rotenone produced effects on colony development similar to those of CCCP. Assays of peroxides using 2',7'-dichlorofluorescin diacetate and fluorescent microscopy suggest a moderate difference in ROS formation between the antimycin and rotenone treatments. The second site of ROS formation (the interface between coenzyme Q and complex III) may thus

  20. Iron toxicity in yeast.

    Science.gov (United States)

    Wiśnicka, R; Krzepiłko, A; Wawryn, J; Biliński, T

    1997-01-01

    It has been found that yeast cells are sensitive to iron overload only when grown on glucose as a carbon source. Effective concentration of ferrous iron is much higher than that found in natural environments. Effects of ferrous iron are strictly oxygen dependent, what suggest that the formation of hydroxyl radicals in the Fenton reaction is a cause of the toxicity. Respiratory deficiency and pretreatment of cells with antimycin A prevent toxic effects in the late exponential phase of growth, whereas uncouplers and 2mM magnesium salts completely protect even the most vulnerable exponential cells. Generally, toxic effects correlate with the ability of cells to take up this metal. The results presented suggest that during ferrous iron overload iron is transported through the unspecific divalent cation uptake system which is known in fungi. The data suggest that recently described high and low affinity systems of iron uptake in yeast are the only source of iron in natural environments. PMID:9516981

  1. Oxidative phosphorylation during glycollate metabolism in mitochondria from phototrophic Euglena gracilis.

    Science.gov (United States)

    Collins, N; Brown, R H; Merrett, M J

    1975-09-01

    Mitochondria were isolated by gradient centrifugation on linear sucrose gradients from broken cell suspensions of phototrophically grown Euglena gracilis. An antimycin A-sensitive but rotenone-insensitive glycollate-dependent oxygen uptake was demonstrated in isolated mitochondria. The partial reactions of glycollate-cytochrome c oxidoreductase and cytochrome c oxidase were demonstrated by using Euglena cytochrome c as exogenous electron acceptor/donor. Isolated mitochondria contain glycollate dehydrogenase and glyoxylate-glutamate aminotransferase and oxidize exogenous glycine. A P:O ratio of 1.7 was obtained for glycollate oxidation, consistent with glycollate electrons entering the Euglena respiratory chain at the flavoprotein level. The significance of these results is discussed in relation to photorespiration in algae. PMID:813630

  2. Genetic modification of alternative respiration in Nicotiana benthamiana affects basal and salicylic acid-induced resistance to potato virus X

    Directory of Open Access Journals (Sweden)

    Verchot-Lubicz Jeanmarie

    2011-02-01

    Full Text Available Abstract Background Salicylic acid (SA regulates multiple anti-viral mechanisms, including mechanism(s that may be negatively regulated by the mitochondrial enzyme, alternative oxidase (AOX, the sole component of the alternative respiratory pathway. However, studies of this mechanism can be confounded by SA-mediated induction of RNA-dependent RNA polymerase 1, a component of the antiviral RNA silencing pathway. We made transgenic Nicotiana benthamiana plants in which alternative respiratory pathway capacity was either increased by constitutive expression of AOX, or decreased by expression of a dominant-negative mutant protein (AOX-E. N. benthamiana was used because it is a natural mutant that does not express a functional RNA-dependent RNA polymerase 1. Results Antimycin A (an alternative respiratory pathway inducer and also an inducer of resistance to viruses and SA triggered resistance to tobacco mosaic virus (TMV. Resistance to TMV induced by antimycin A, but not by SA, was inhibited in Aox transgenic plants while SA-induced resistance to this virus appeared to be stronger in Aox-E transgenic plants. These effects, which were limited to directly inoculated leaves, were not affected by the presence or absence of a transgene constitutively expressing a functional RNA-dependent RNA polymerase (MtRDR1. Unexpectedly, Aox-transgenic plants infected with potato virus X (PVX showed markedly increased susceptibility to systemic disease induction and virus accumulation in inoculated and systemically infected leaves. SA-induced resistance to PVX was compromised in Aox-transgenic plants but plants expressing AOX-E exhibited enhanced SA-induced resistance to this virus. Conclusions We conclude that AOX-regulated mechanisms not only play a role in SA-induced resistance but also make an important contribution to basal resistance against certain viruses such as PVX.

  3. L-pipecolic acid catabolism in mammals

    International Nuclear Information System (INIS)

    The goal of the project was to study L-pipecolic acid metabolism in mammals. Initially, homogenized rabbit kidney cortices were incubated with L-[2,3,4,5,6-3H]pipecolic acid. Anion exchange resin was used to separate the reaction product from the substrate. When the radioactive product eluted from the anion exchange column was separated by citrate buffer column chromatography, only one major radioactive peak was found. This peak coeluted with authentic α-aminoadipic acid. When organelles from both kidney and liver were separated on Percoll gradients, L-pipecolic acid oxidation paralleled the mitochondrial marker glutamate dehydrogenase. L-Pipecolic acid oxidation was inhibited by rotenone and antimycin A and was found to occur in the soluble fraction of the mitochondria. FAD, glycerol, and phenazine ethosulfate all increased oxidative activity. L-Proline, and other compounds which are structurally similar to L-pipecolic acid did not inhibit oxidative activity

  4. Effect of simvastatin on vascular tone in porcine coronary artery: Potential role of the mitochondria.

    Science.gov (United States)

    Almukhtar, H; Garle, M J; Smith, P A; Roberts, R E

    2016-08-15

    Statins induce acute vasorelaxation which may contribute to the overall benefits of statins in the treatment of cardiovascular disease. The mechanism underlying this relaxation is unknown. As statins have been shown to alter mitochondrial function, in this study we investigated the role of mitochondria in the relaxation to simvastatin. Relaxation of porcine coronary artery segments by statins was measured using isolated tissue baths. Mitochondrial activity was determined by measuring changes in rhodamine 123 fluorescence. Changes in intracellular calcium levels were determined in freshly isolated smooth muscle cells with Fluo-4 using standard epifluorescent imaging techniques. Simvastatin, but not pravastatin, produced a slow relaxation of the coronary artery, which was independent of the endothelium. The relaxation was attenuated by the mitochondrial complex I inhibitor rotenone (10μM) and the complex III inhibitor myxothiazol (10μM), or a combination of the two. The complex III inhibitor antimycin A (10μM) produced a similar time-dependent relaxation of the porcine coronary artery, which was attenuated by rotenone. Changes in rhodamine 123 fluorescence showed that simvastatin (10μM) depolarized the membrane potential of mitochondria in both isolated mitochondria and intact blood vessels. Simvastatin and antimycin A both inhibited calcium-induced contractions in isolated blood vessels and calcium influx in smooth muscle cells and this inhibition was prevented by rotenone. In conclusion, simvastatin produces an endothelium-independent relaxation of the porcine coronary artery which is dependent, in part, upon effects on the mitochondria. The effects on the mitochondria may lead to a reduction in calcium influx and hence relaxation of the blood vessel. PMID:27343404

  5. Chemical basis of the synergism and antagonism in microbial communities in the nests of leaf-cutting ants.

    Science.gov (United States)

    Schoenian, Ilka; Spiteller, Michael; Ghaste, Manoj; Wirth, Rainer; Herz, Hubert; Spiteller, Dieter

    2011-02-01

    Leaf-cutting ants cultivate the fungus Leucoagaricus gongylophorus, which serves as a major food source. This symbiosis is threatened by microbial pathogens that can severely infect L. gongylophorus. Microbial symbionts of leaf-cutting ants, mainly Pseudonocardia and Streptomyces, support the ants in defending their fungus gardens against infections by supplying antimicrobial and antifungal compounds. The ecological role of microorganisms in the nests of leaf-cutting ants can only be addressed in detail if their secondary metabolites are known. Here, we use an approach for the rapid identification of established bioactive compounds from microorganisms in ecological contexts by combining phylogenetic data, database searches, and liquid chromatography electrospray ionisation high resolution mass spectrometry (LC-ESI-HR-MS) screening. Antimycins A(1)-A(4), valinomycins, and actinomycins were identified in this manner from Streptomyces symbionts of leaf-cutting ants. Matrix-assisted laser desorption ionization (MALDI) imaging revealed the distribution of valinomycin directly on the integument of Acromyrmex echinatior workers. Valinomycins and actinomycins were also directly identified in samples from the waste of A. echinatior and A. niger leaf-cutting ants, suggesting that the compounds exert their antimicrobial and antifungal potential in the nests of leaf-cutting ants. Strong synergistic effects of the secondary meta-bolites produced by ant-associated Streptomyces were observed in the agar diffusion assay against Escovopsis weberi. Actinomycins strongly inhibit soil bacteria as well as other Streptomyces and Pseudonocardia symbionts. The antifungal antimycins are not only active against pathogenic fungi but also the garden fungus L. gongylophorus itself. In conclusion, secondary metabolites of microbial symbionts of leaf-cutting ants contribute to shaping the microbial communities within the nests of leaf-cutting ants. PMID:21245311

  6. On the location of the H+-extruding steps in site 2 of the mitochondrial electron transport chain.

    Science.gov (United States)

    Alexandre, A; Galiazzo, F; Lehninger, A L

    1980-11-25

    The location of the H+-translocating reactions within energy-conserving Site 2 of the mitochondrial electron transport chain was evaluated from two sets of data. In the first, the H+/2e- ejection ratios and Ca2+/2e- uptake ratios were compared for electron flow from succinate dehydrogenase, whose active site is on the matrix side of the inner membrane and from glycerol phosphate dehydrogenase, whose active site is on the cytosolic side. In intact rat liver mitochondria both substrates yielded H+/2e- ejection ratios close to 4.0 and Ca2+/2e- uptake ratios close to 1.0 during antimycin-sensitive reduction of ferricyanide. With rat liver mitoplasts and ferricytochrome c as electron acceptor, both substrates again gave the same stoichiometric ratios. The second approach involved determination of the sidedness of H+ formation during electron flow from succinate to ferricyanide via bypass of the antimycin block of the cytochrome b.c1 complex provided by N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), under conditions in which the TMPD-TMPD+ couple does not act as a membrane-penetrating protonophore. Electron flow in this system was inhibited by 2-then-oyltrifluoroacetone, indicating that TMPD probably accepts electrons from ubiquinol. The 2 H+ formed in this system were not delivered into the matrix but appeared directly in the medium in the absence of a protonophore. To accommodate the available evidence on Site 2 substrates, it is concluded that the substrate hydrogens are first transferred to ubiquinone, 2 H+ per 2e then appear in the medium by protolytic dehydrogenation of a species of ubiquinol or ubiquinol-protein having the appropriate sidedness (designated Site 2A), and the other 2 H+ are translocated from the matrix to the medium on passage of 2e- through the cytochrome b x c1 complex (designated Site 2B). PMID:7430148

  7. Low level laser therapy activates NF-kB via generation of reactive oxygen species in mouse embryonic fibroblasts

    Science.gov (United States)

    Chen, Aaron Chih-Hao; Arany, Praveen R.; Huang, Ying-Ying; Tomkinson, Elizabeth M.; Saleem, Taimur; Yull, Fiona E.; Blackwell, Timothy S.; Hamblin, Michael R.

    2009-02-01

    Despite over forty years of investigation on low-level light therapy (LLLT), the fundamental mechanisms underlying photobiomodulation remain unclear. In this study, we isolated murine embryonic fibroblasts (MEF) from transgenic NF-kB luciferase reporter mice and studied their response to 810-nm laser radiation. Significant activation of NFkB was observed for fluences higher than 0.003 J/cm2. NF-kB activation by laser was detectable at 1-hour time point. Moreover, we demonstrated that laser phosphorylated both IKK α/β and NF-kB 15 minutes after irradiation, which implied that laser activates NF-kB via phosphorylation of IKK α/β. Suspecting mitochondria as the source of NF-kB activation signaling pathway, we demonstrated that laser increased both intracellular reactive oxygen species (ROS) by fluorescence microscopy with dichlorodihydrofluorescein and ATP synthesis by luciferase assay. Mitochondrial inhibitors, such as antimycin A, rotenone and paraquat increased ROS and NF-kB activation but had no effect on ATP. The ROS quenchers N-acetyl-L-cysteine and ascorbic acid abrogated laser-induced NF-kB and ROS but not ATP. These results suggested that ROS might play an important role in the signaling pathway of laser induced NF-kB activation. However, the western blot showed that antimycin A, a mitochondrial inhibitor, did not activate NF-kB via serine phosphorylation of IKK α/β as the laser did. On the other hand, LLLT, unlike mitochondrial inhibitors, induced increased cellular ATP levels, which indicates that light also upregulates mitochondrial respiration. ATP upregulation reached a maximum at 0.3 J/cm2 or higher. We conclude that LLLT not only enhances mitochondrial respiration, but also activates the redox-sensitive transcription factor NF-kB by generating ROS as signaling molecules.

  8. Correlation between photosynthesis and the transthylakoid proton gradient

    Energy Technology Data Exchange (ETDEWEB)

    Slovacek, R.E.; Hind, G.

    1981-01-01

    In isolated intact chloroplasts, maximal rates of photosynthetic O/sub 2/ evolution (in saturating HCO/sup -//sub 3/) are associated with a critical transthylakoid proton gradient as a result of the stoichiometric consumption of 2 mol NADPH and 3 mol ATP/mol CO/sub 2/ fixed. Studies with the fluorescent probe 9-aminoacridine reveal that in the illuminated steady state the critical ..delta..pH is 3.9. CO/sub 2/-dependent O/sub 2/ evolution is inhibited by increases of 0.1 to 0.2 in ..delta..pH that occur when catalase is omitted from the medium, NO/sup -//sub 2/ is included as an electron acceptor, or when chloroplasts are illuminated under low partial pressures of O/sub 2/. Low concentrations of antimycin (0.33 ..mu..M) or NH/sub 4/Cl (0.33 mM) decrease ..delta..pH and relieve this inhibition of electron flow. The energy transfer inhibitor quercetin lowers the high ATP/ADP ratio associated with these conditions, but does not lower ..delta..pH or relieve the inhibition. A decrease of ..delta..pH below 3.9 by weaker illumination, millimolar levels of NH/sub 4/Cl or micromolar levels of antimycin, results in lower rates of photosynthesis owing to limitation by the phosphorylation rate. These findings show that in absence of rate limitation by the carbon cycle, the extent of thylakoid energization is related to the ratio of ATP to NADPH production and in turn, the rate of CO/sub 2/ assimilation.

  9. The influence of cryopreservation on parameters of energetic metabolism and motility of fowl spermatozoa.

    Science.gov (United States)

    Ochkur, S I; Kopeika, E F; Suraj, P F; Grishchenko, V I

    1994-06-01

    The objective of this study was to estimate the effect of cryopreservation on the main pathways of energetic metabolism and motility of fowl spermatozoa. Sperm diluted 1:5 with the cryoprotective medium containing ethylene glycol (1.4 M final concentration) was frozen at the rate of 2-3 degrees C/min to -25 degrees C with a pause on the plateau of crystallization and then at an exponentially increasing rate to -196 degrees C. The frozen sperm was thawed in two successive water baths at 0 and at 41 degrees C. After cryopreservation, the rate of radioactive glucose oxidation to 14CO2 slightly decreased, the rate of labeled glutamate oxidation remained unchanged, and the rate of labeled succinate oxidation increased two-fold. After freeze-thawing, the rates of endogenous respiration with and without 2,4-dinitrophenol decreased; the oxidation rate of exogenous succinate in the presence of 2,4-dinitrophenol, rotenone, and digitonin slightly decreased; and the rate of respiration in the presence of ascorbate, N,N,N',N'-tetramethyl-p-phenylenediamine, antimycin A, 2,4-dinitrophenol, and digitonin did not differ from that seen in control. Sperm respiration was highly sensitive to rotenone; antimycin A and cyanide blocked oxygen consumption completely. Succinate, added after 2,4-dinitrophenol and rotenone, stimulated respiration of thawed spermatozoa, which indicated plasma membrane damage. The addition of exogenous malate in the presence of 2,4-dinitrophenol and digitonin restored the respiration rate of thawed spermatozoa to that of unfrozen cells. The rate of respiration of thawed spermatozoa with oligomycin was higher than that of control cells.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8050269

  10. Mitochondrial Malfunctioning, Proteasome Arrest and Apoptosis in Cancer Cells by Focused Intracellular Generation of Oxygen Radicals

    Directory of Open Access Journals (Sweden)

    Ilaria Postiglione

    2015-08-01

    Full Text Available Photofrin/photodynamic therapy (PDT at sub-lethal doses induced a transient stall in proteasome activity in surviving A549 (p53+/+ and H1299 (p53−/− cells as indicated by the time-dependent decline/recovery of chymotrypsin-like activity. Indeed, within 3 h of incubation, Photofrin invaded the cytoplasm and localized preferentially within the mitochondria. Its light activation determined a decrease in mitochondrial membrane potential and a reversible arrest in proteasomal activity. A similar result is obtained by treating cells with Antimycin and Rotenone, indicating, as a common denominator of this effect, the ATP decrease. Both inhibitors, however, were more toxic to cells as the recovery of proteasomal activity was incomplete. We evaluated whether combining PDT (which is a treatment for killing tumor cells, per se, and inducing proteasome arrest in the surviving ones with Bortezomib doses capable of sustaining the stall would protract the arrest with sufficient time to induce apoptosis in remaining cells. The evaluation of the mitochondrial membrane depolarization, residual proteasome and mitochondrial enzymatic activities, colony-forming capabilities, and changes in protein expression profiles in A549 and H1299 cells under a combined therapeutic regimen gave results consistent with our hypothesis.

  11. Simultaneous Fluorescence and Phosphorescence Lifetime Imaging Microscopy in Living Cells

    Science.gov (United States)

    Jahn, Karolina; Buschmann, Volker; Hille, Carsten

    2015-09-01

    In living cells, there are always a plethora of processes taking place at the same time. Their precise regulation is the basis of cellular functions, since small failures can lead to severe dysfunctions. For a comprehensive understanding of intracellular homeostasis, simultaneous multiparameter detection is a versatile tool for revealing the spatial and temporal interactions of intracellular parameters. Here, a recently developed time-correlated single-photon counting (TCSPC) board was evaluated for simultaneous fluorescence and phosphorescence lifetime imaging microscopy (FLIM/PLIM). Therefore, the metabolic activity in insect salivary glands was investigated by recording ns-decaying intrinsic cellular fluorescence, mainly related to oxidized flavin adenine dinucleotide (FAD) and the μs-decaying phosphorescence of the oxygen-sensitive ruthenium-complex Kr341. Due to dopamine stimulation, the metabolic activity of salivary glands increased, causing a higher pericellular oxygen consumption and a resulting increase in Kr341 phosphorescence decay time. Furthermore, FAD fluorescence decay time decreased, presumably due to protein binding, thus inducing a quenching of FAD fluorescence decay time. Through application of the metabolic drugs antimycin and FCCP, the recorded signals could be assigned to a mitochondrial origin. The dopamine-induced changes could be observed in sequential FLIM and PLIM recordings, as well as in simultaneous FLIM/PLIM recordings using an intermediate TCSPC timing resolution.

  12. [Characteristics of the respiratory chain and the oxidative phosphorylation system of mitochondria in the flavinogenic Eremothecium ashbyii strain].

    Science.gov (United States)

    Zviagil'skaia, R A; Korosteleva, N L; Mironov, V A

    1976-01-01

    Tightly coupled mitochondria were isolated from cells of the flavinogenic strain of Eremothecium ashbyii collected during the logarithmic and stationary growth phases. The composition of the respiratory chain and characteristics of the energy coupling system are described. The mitochondria show a wide spectrum of metabolic activity and oxidize Krebs cycle compenents and exogenous NADH. The terminal segment of the respiratory chain is represented by a typical cytochrome system. The mitochondria of the ascomycete collected during the logarithmic growth phase are characterized by a relatively high content of cytochromes b and c, a high rate of oxidation of NAD-dependent substrates, the presence of lower homologues of ubiquinone, UQ6 and UQ7, and extremely high sensitivity of respiration to the action of antimycin A, low content of a component sensitive to rotenone, contrasting with the operation of all three sites of phosphorylation. Transition to the stationary growth phase is accompanied with a decrease in the rate of oxidation of all substrates studied and a declined effectiveness of oxidative phosphorylation. The data obtained are discussed in relation to the ability of the cells for "overproduction" of flavins. PMID:187903

  13. Synergism of Antifungal Activity between Mitochondrial Respiration Inhibitors and Kojic Acid

    Directory of Open Access Journals (Sweden)

    Ronald P. Haff

    2013-01-01

    Full Text Available Co-application of certain types of compounds to conventional antimicrobial drugs can enhance the efficacy of the drugs through a process termed chemosensitization. We show that kojic acid (KA, a natural pyrone, is a potent chemosensitizing agent of complex III inhibitors disrupting the mitochondrial respiratory chain in fungi. Addition of KA greatly lowered the minimum inhibitory concentrations of complex III inhibitors tested against certain filamentous fungi. Efficacy of KA synergism in decreasing order was pyraclostrobin > kresoxim-methyl > antimycin A. KA was also found to be a chemosensitizer of cells to hydrogen peroxide (H2O2, tested as a mimic of reactive oxygen species involved in host defense during infection, against several human fungal pathogens and Penicillium strains infecting crops. In comparison, KA-mediated chemosensitization to complex III inhibitors/H2O2 was undetectable in other types of fungi, including Aspergillus flavus, A. parasiticus, and P. griseofulvum, among others. Of note, KA was found to function as an antioxidant, but not as an antifungal chemosensitizer in yeasts. In summary, KA could serve as an antifungal chemosensitizer to complex III inhibitors or H2O2 against selected human pathogens or Penicillium species. KA-mediated chemosensitization to H2O2 seemed specific for filamentous fungi. Thus, results indicate strain- and/or drug-specificity exist during KA chemosensitization.

  14. Molecular Characterization of Endoplasmic Reticulum Oxidoreductin 1 from Bombyx mori

    Directory of Open Access Journals (Sweden)

    Minchul Seo

    2015-11-01

    Full Text Available We isolated a complementary DNA (cDNA clone encoding endoplasmic reticulum oxidoreductin 1 (bERO1, a specific oxidant of protein disulfide isomerase (PDI from Bombyx mori. This protein has a putative open reading frame (ORF of 489 amino acids and a predicted size of 57.4 kDa. Although bERO1 protein shares less than 57% amino acid sequence homology with other reported ERO1s, it contains two conserved redox active motifs, a Cys-X-X-X-X-Cys motif of N-terminal and Cys-X-X-Cys-X-X-Cys motif of C-terminal. Both motifs are typically present in ERO1 protein family members. The bEro1 mRNA expression was highest in posterior silk gland on the sixth day of the 5th instar larvae. Expression of bEro1 mRNA also markedly increased during endoplasmic reticulum (ER stress induced by stimulation with antimycin, calcium ionophore A23187, dithiothreitol, H2O2, monencin, and tunicamycin. In addition, expression levels of bEro1 exactly coincided with that of bPdi. This is the first result suggesting that bERO1 plays an essential role in ER quality control through the combined activities of bERO1 and bPDI as a catalyst of protein folding in the ER and sustaining cellular redox homeostasis.

  15. Brief exposure to carbon monoxide preconditions cardiomyogenic cells against apoptosis in ischemia-reperfusion

    International Nuclear Information System (INIS)

    We examined whether and how pretreatment with carbon monoxide (CO) prevents apoptosis of cardioblastic H9c2 cells in ischemia-reperfusion. Reperfusion (6 h) following brief ischemia (10 min) induced cytochrome c release, activation of caspase-9 and caspase-3, and apoptotic nuclear condensation. Brief CO pretreatment (10 min) or a caspase-9 inhibitor (Z-LEHD-FMK) attenuated these apoptotic changes. Ischemia-reperfusion increased phosphorylation of Akt at Ser472/473/474, and this was enhanced by CO pretreatment. A specific Akt inhibitor (API-2) blunted the anti-apoptotic effects of CO in reperfusion. In normoxic cells, CO enhanced O2- generation, which was inhibited by a mitochondrial complex III inhibitor (antimycin A) but not by a NADH oxidase inhibitor (apocynin). The CO-enhanced Akt phosphorylation was suppressed by an O2- scavenger (Tiron), catalase or a superoxide dismutase (SOD) inhibitor (DETC). These results suggest that CO pretreatment induces mitochondrial generation of O2-, which is then converted by SOD to H2O2, and subsequent Akt activation by H2O2 attenuates apoptosis in ischemia-reperfusion.

  16. Involvement of sulfide:quinone oxidoreductase in sulfur oxidation of an acidophilic iron-oxidizing bacterium, Acidithiobacillus ferrooxidans NASF-1.

    Science.gov (United States)

    Wakai, Satoshi; Kikumoto, Mei; Kanao, Tadayoshi; Kamimura, Kazuo

    2004-12-01

    The effects of cyanide, azide, and 2-n-Heptyl-4-hydroxy-quinoline-N-oxide (HQNO) on the oxidation of ferrous ion or elemental sulfur with Acidithiobacillus ferrooxidans NASF-1 cells grown in iron- or sulfur-medium were examined. The iron oxidation of both iron- and sulfur-grown cells was strongly inhibited by cyanide and azide, but not by HQNO. Sulfur oxidation was relatively resistant to cyanide and azide, and inhibited by HQNO. Higher sulfide oxidation, ubiquinol dehydrogenase activity, and sulfide:quinone oxidoreductase (SQR) activity were observed in sulfur-grown cells more than in iron-grown cells. Sulfide oxidation in the presence of ubiquinone with the membrane fraction was inhibited by HQNO, but not by cyanide, azide, antimycin A, and myxothiazol. The transcription of three genes, encoding an aa(3)-type cytochrome c oxidase (coxB), a bd-type ubiquinol oxidase (cydA), and an sqr, were measured by real-time reverse transcription polymerase chain reaction. The transcriptional levels of coxB and cydA genes were similar in sulfur- and iron-grown cells, but that of sqr was 3-fold higher in sulfur-grown cells than in iron-grown cells. A model is proposed for the oxidation of reduced inorganic sulfur compounds in A. ferrooxidans NASF-1 cells. PMID:15618623

  17. Uptake of corticosterone into isolated rat liver cells: possible involvement of Na+/K(+)-ATPase.

    Science.gov (United States)

    Spindler, K D; Kanuma, K; Grossmann, D

    1991-06-01

    Isolated rat hepatocytes possess a saturable glucocorticoid uptake system with high affinity (Kd value = 2.8 +/- 0.7 x 10(-8) M; 318,000 +/- 80,000 binding sites per cell; 317 fmol/mg protein). The initial rates of uptake decrease by about 30-40% if the cells are incubated simultaneously with [3H]corticosterone and either SH-reagents (N-ethylmaleimide and p-chloromercuriphenylsulphonate, 1 mM), metabolic inhibitors (2,4-dinitrophenol, 1 mM; and antimycin, 0.1 mM) or the Na+/K(+)-ATPase-inhibitors, ouabain and quercetine. These Na+/K(+)-ATPase-blockers exert half-maximal inhibition at 3 x 10(-7) and 3 x 10(-6) M, respectively. A slight increase in K+ concentration and a corresponding decrease in Na+ in the medium leads to a significant reduction in the initial uptake rate. The uptake system from the rat hepatocytes shows a clear steroid specificity, being different from the intracellular receptor. Corticosterone and progesterone are the strongest competitors, cortisol, 5 alpha- and 5 beta-dihydrocorticosterone, 11-deoxycorticosterone, cortisone and testosterone have an intermediate effect and only weak competition is exerted by dexamethasone and by the mineralocorticoid, aldosterone. Estradiol and estrone sulphate as well as the synthetic glucocorticoid triamcinolone acetonide are unable to inhibit initial corticosterone uptake. PMID:1648377

  18. Deoxyactein stimulates osteoblast function and inhibits bone-resorbing mediators in MC3T3-E1 cells.

    Science.gov (United States)

    Choi, Eun Mi

    2013-03-01

    Osteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. In order to improve the treatment of osteoporosis, identification of anabolic agents with minimal side effects is highly desirable. Cimicifuga racemosa has a long and diverse history of medicinal use and deoxyactein isolated from this species is one of the major constituents. In the present study, the effect of deoxyactein on the function of osteoblastic MC3T3-E1 cells was studied. Deoxyactein caused a significant elevation of cell growth, alkaline phosphatase activity, collagen content, and mineralization in the cells (P < 0.05). Moreover, deoxyactein significantly (P < 0.05) decreased the production of reactive oxygen species (ROS) and osteoclast differentiation-inducing factors such as TNF-α, IL-6 and receptor activator of nuclear factor-κB ligand in the presence of antimycin A, which inhibits mitochondrial electron transport and has been used as an ROS generator. These results demonstrate that deoxyactein may have positive effects on skeletal structure. PMID:21910134

  19. Expression of Vitreoscilla hemoglobin enhances growth and levels of alpha-amylase in Schwanniomyces occidentalis.

    Science.gov (United States)

    Suthar, Devesh H; Chattoo, Bharat B

    2006-08-01

    A metabolic engineering approach was exploited to improve growth and protein secretion in the non-conventional yeast, Schwanniomyces occidentalis. Vitreoscilla hemoglobin (VHb) gene was expressed in S. occidentalis under the control of the native alpha-amylase (AMY1) promoter. Expression of VHb was confirmed by reverse transcriptase polymerase chain reaction and Western blot hybridization analysis. Effect of VHb on growth and protein secretion was studied in synthetic medium under both limiting and non-limiting dissolved oxygen conditions. Under both conditions, VHb-expressing cells exhibited higher oxygen uptake and higher specific growth rates. Levels of extracellular alpha-amylase were also elevated in the VHb-transformed strain relative to the control strain. In amylase production medium, VHb-expressing cells showed 3-fold elevated levels of alpha-amylase and a 31% increase in the total secreted protein under oxygen-limiting environment. VHb was found to localize in the mitochondria in addition to its cytoplasmic location. Inhibition of respiration by antimycin A resulted in the loss of the growth-enhancing effects of VHb. A 2.5-fold increase in the cytochrome c oxidase (COX) activity was observed in VHb-expressing cells relative to the control. In addition to this, exogenously added VHb in the assay mixture augmented COX activity. PMID:16642333

  20. Atmospheric Dispersal of Bioactive Streptomyces albidoflavus Strains Among Terrestrial and Marine Environments.

    Science.gov (United States)

    Sarmiento-Vizcaíno, Aida; Braña, Alfredo F; González, Verónica; Nava, Herminio; Molina, Axayacatl; Llera, Eva; Fiedler, Hans-Peter; Rico, José M; García-Flórez, Lucía; Acuña, José L; García, Luis A; Blanco, Gloria

    2016-02-01

    Members of the Streptomyces albidoflavus clade, identified by 16S rRNA sequencing and phylogenetic analyses, are widespread among predominant terrestrial lichens (Flavoparmelia caperata and Xanthoria parietina) and diverse intertidal and subtidal marine macroalgae, brown red and green (Phylum Heterokontophyta, Rhodophyta, and Chlorophyta) from the Cantabrian Cornice. In addition to these terrestrial and coastal temperate habitats, similar strains were also found to colonize deep-sea ecosystems and were isolated mainly from gorgonian and solitary corals and other invertebrates (Phylum Cnidaria, Annelida, Echinodermata, Arthropoda, and Porifera) living up to 4700-m depth and at a temperature of 2-4 °C in the submarine Avilés Canyon. Similar strains have been also repeatedly isolated from atmospheric precipitations (rain drops, snow, and hailstone) collected in the same area throughout a year observation time. These ubiquitous strains were found to be halotolerant, psychrotolerant, and barotolerant. Bioactive compounds with diverse antibiotic and cytotoxic activities produced by these strains were identified by high-performance liquid chromatography (HPLC) and database comparison. These include antibacterials (paulomycins A and B), antifungals (maltophilins), antifungals displaying also cytotoxic activities (antimycins and 6-epialteramides), and the antitumor compound fredericamycin. A hypothetical dispersion model is here proposed to explain the biogeographical distribution of S. albidoflavus strains in terrestrial, marine, and atmospheric environments. PMID:26224165

  1. Expression of the Ciona intestinalis alternative oxidase (AOX) in Drosophila complements defects in mitochondrial oxidative phosphorylation.

    Science.gov (United States)

    Fernandez-Ayala, Daniel J M; Sanz, Alberto; Vartiainen, Suvi; Kemppainen, Kia K; Babusiak, Marek; Mustalahti, Eero; Costa, Rodolfo; Tuomela, Tea; Zeviani, Massimo; Chung, Jongkyeong; O'Dell, Kevin M C; Rustin, Pierre; Jacobs, Howard T

    2009-05-01

    Defects in mitochondrial OXPHOS are associated with diverse and mostly intractable human disorders. The single-subunit alternative oxidase (AOX) found in many eukaryotes, but not in arthropods or vertebrates, offers a potential bypass of the OXPHOS cytochrome chain under conditions of pathological OXPHOS inhibition. We have engineered Ciona intestinalis AOX for conditional expression in Drosophila melanogaster. Ubiquitous AOX expression produced no detrimental phenotype in wild-type flies. However, mitochondrial suspensions from AOX-expressing flies exhibited a significant cyanide-resistant substrate oxidation, and the flies were partially resistant to both cyanide and antimycin. AOX expression was able to complement the semilethality of partial knockdown of both cyclope (COXVIc) and the complex IV assembly factor Surf1. It also rescued the locomotor defect and excess mitochondrial ROS production of flies mutated in dj-1beta, a Drosophila homolog of the human Parkinson's disease gene DJ1. AOX appears to offer promise as a wide-spectrum therapeutic tool in OXPHOS disorders. PMID:19416715

  2. Investigations on the mechanism of oxygen-dependent plant processes: ethylene biosynthesis and cyanide-resistant respiration

    International Nuclear Information System (INIS)

    Two oxygen-dependent plant processes were investigated. A cell-free preparation from pea (Pisum sativum L., cv. Alaska) was used to study ethylene biosynthesis from 1-aminocyclopropane-1-carboxylic acid. Mitochondrial cyanide-resistant respiration was investigated in studies with 14C-butyl gallate and other respiratory effectors. Ethylene biosynthesis was not due to a specific enzyme, or oxygen radicals. Rather, hydrogen peroxide, generated at low levels, coupled with endogenous manganese produced ethylene. 14C-butyl gallate bound specifically to mitochondria from cyanide-sensitive and -resistant higher plants and Neurospora crassa mitochondria. The amount of gallate bound was similar for all higher plant mitochondria. Rat liver mitochondria bound very little 14C-butyl gallate. Plant mitochondria in which cyanide-resistance was induced bound as much 14C-butyl gallate as before induction. However mitochondria from recently harvested white potato tubers did not bind the gallate. The observations suggest that an engaging factor couples with a gallate binding site in the mitochondrial membrane. With skunk cabbage spadix mitochondria the I50 for antimycin A inhibition of oxygen uptake was decreased by salicylhydroxamic acid pretreatment; this was also true for reverse order additions. No shift was observed with mung bean hypocotyl or Jerusalem artichoke tuber mitochondria

  3. Purification and some properties of ubiquinol oxidase from obligately chemolithotrophic iron-oxidizing bacterium, Thiobacillus ferrooxidans NASF-1.

    Science.gov (United States)

    Kamimura, K; Fujii, S; Sugio, T

    2001-01-01

    Ubiquinol-oxidizing activity was detected in an acidophilic chemolithotrophic iron-oxidizing bacterium, T. ferrooxidans. The ubiquinol oxidase was purified 79-fold from plasma membranes of T. ferrooxidans NASF-1 cells. The purified oxidase is composed of two polypeptides with apparent molecular masses of 32,600 and 50,100 Da, as measured by gel electrophoresis in the presence of sodium dodecyl sulfate. The absorption spectrum of the reduced enzyme at room temperature showed big peaks at 530 and 563, and a small broad peak at 635 nm, indicating the involvement of cytochromes b and d. Characteristic peaks of cytochromes a and c were not observed in the spectrum at around 600 and 550 nm, respectively. This enzyme combined with CO, and its CO-reduced minus reduced difference spectrum showed peaks at 409 nm and 563 nm and a trough at 431 nm. These results indicated that the oxidase contained cytochrome b, but the involvement of cytochrome d was not clear. The enzyme catalyzed the oxidations of ubiquinol-2 and reduced N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride. The ubiquinol oxidase activity was activated by the addition of albumin and lecithin to the reaction mixture and inhibited by the respiratory inhibitors KCN, HQNO, NaN3, and antimycin A1, although the enzyme was relatively resistant to KCN, and the divalent cation, Zn2+, compared with ubiquinol oxidases of E. coli. PMID:11272847

  4. Mitochondria mediate tumor necrosis factor-alpha/NF-kappaB signaling in skeletal muscle myotubes

    Science.gov (United States)

    Li, Y. P.; Atkins, C. M.; Sweatt, J. D.; Reid, M. B.; Hamilton, S. L. (Principal Investigator)

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is implicated in muscle atrophy and weakness associated with a variety of chronic diseases. Recently, we reported that TNF-alpha directly induces muscle protein degradation in differentiated skeletal muscle myotubes, where it rapidly activates nuclear factor kappaB (NF-kappaB). We also have found that protein loss induced by TNF-alpha is NF-kappaB dependent. In the present study, we analyzed the signaling pathway by which TNF-alpha activates NF-kappaB in myotubes differentiated from C2C12 and rat primary myoblasts. We found that activation of NF-kappaB by TNF-alpha was blocked by rotenone or amytal, inhibitors of complex I of the mitochondrial respiratory chain. On the other hand, antimycin A, an inhibitor of complex III, enhanced TNF-alpha activation of NK-kappaB. These results suggest a key role of mitochondria-derived reactive oxygen species (ROS) in mediating NF-kappaB activation in muscle. In addition, we found that TNF-alpha stimulated protein kinase C (PKC) activity. However, other signal transduction mediators including ceramide, Ca2+, phospholipase A2 (PLA2), and nitric oxide (NO) do not appear to be involved in the activation of NF-kappaB.

  5. Iron speciation in human cancer cells by K-edge total reflection X-ray fluorescence-X-ray absorption near edge structure analysis

    Science.gov (United States)

    Polgári, Zs.; Meirer, F.; Sasamori, S.; Ingerle, D.; Pepponi, G.; Streli, C.; Rickers, K.; Réti, A.; Budai, B.; Szoboszlai, N.; Záray, G.

    2011-03-01

    X-ray absorption near edge structure (XANES) analysis in combination with synchrotron radiation induced total reflection X-ray fluorescence (SR-TXRF) acquisition was used to determine the oxidation state of Fe in human cancer cells and simultaneously their elemental composition by applying a simple sample preparation procedure consisting of pipetting the cell suspension onto the quartz reflectors. XANES spectra of several inorganic and organic iron compounds were recorded and compared to that of different cell lines. The XANES spectra of cells, independently from the phase of cell growth and cell type were very similar to that of ferritin, the main Fe store within the cell. The spectra obtained after CoCl 2 or NiCl 2 treatment, which could mimic a hypoxic state of cells, did not differ noticeably from that of the ferritin standard. After 5-fluorouracil administration, which could also induce an oxidative-stress in cells, the absorption edge position was shifted toward higher energies representing a higher oxidation state of Fe. Intense treatment with antimycin A, which inhibits electron transfer in the respiratory chain, resulted in minor changes in the spectrum, resembling rather the N-donor Fe-α,α'-dipyridyl complex at the oxidation energy of Fe(III), than ferritin. The incorporation of Co and Ni in the cells was followed by SR-TXRF measurements.

  6. Effect of long-term cyanide exposure on cyanide-sensitive respiration and phosphate metabolism in the fungus Phycomyces blakesleeanus

    Directory of Open Access Journals (Sweden)

    Stanić Marina

    2014-01-01

    Full Text Available The effects of long-term exposure (5 h of Phycomyces blakesleeanus mycelium to 5 mM KCN on respiration and phosphate metabolites were tested. Exposure to cyanide, antimycin A and azide lead to a decrease in the activity of cyanide-sensitive respiration (CSR, and the ratio of core polyphosphates (PPc and inorganic phosphates (Pi, which is a good indicator of the metabolic state of a cell. After 5 h of incubation, the activity of CSR returned to control values. For this, the recovery of cytochrome c oxidase (COX was required. In addition, the PPc/Pi ratio started to recover shortly after initiation of COX recovery, but never reached control values. This led us to conclude that the regulation of polyphosphate (PPn levels in the cell is tightly coupled to respiratory chain functioning. In addition, acutely applied cyanide caused two different responses, observed by 31P NMR spectroscopy, that were probably mediated through the mechanism of glycolytic oscillations, triggered by the effect of cyanide on mitochondria. [Projekat Ministarstva nauke Republike Srbije, br. 173040

  7. Investigations on the mechanism of oxygen-dependent plant processes: ethylene biosynthesis and cyanide-resistant respiration

    Energy Technology Data Exchange (ETDEWEB)

    Stegink, S.J.

    1985-01-01

    Two oxygen-dependent plant processes were investigated. A cell-free preparation from pea (Pisum sativum L., cv. Alaska) was used to study ethylene biosynthesis from 1-aminocyclopropane-1-carboxylic acid. Mitochondrial cyanide-resistant respiration was investigated in studies with /sup 14/C-butyl gallate and other respiratory effectors. Ethylene biosynthesis was not due to a specific enzyme, or oxygen radicals. Rather, hydrogen peroxide, generated at low levels, coupled with endogenous manganese produced ethylene. /sup 14/C-butyl gallate bound specifically to mitochondria from cyanide-sensitive and -resistant higher plants and Neurospora crassa mitochondria. The amount of gallate bound was similar for all higher plant mitochondria. Rat liver mitochondria bound very little /sup 14/C-butyl gallate. Plant mitochondria in which cyanide-resistance was induced bound as much /sup 14/C-butyl gallate as before induction. However mitochondria from recently harvested white potato tubers did not bind the gallate. The observations suggest that an engaging factor couples with a gallate binding site in the mitochondrial membrane. With skunk cabbage spadix mitochondria the I/sub 5//sup 0/ for antimycin A inhibition of oxygen uptake was decreased by salicylhydroxamic acid pretreatment; this was also true for reverse order additions. No shift was observed with mung bean hypocotyl or Jerusalem artichoke tuber mitochondria.

  8. Iron speciation in human cancer cells by K-edge total reflection X-ray fluorescence-X-ray absorption near edge structure analysis

    International Nuclear Information System (INIS)

    X-ray absorption near edge structure (XANES) analysis in combination with synchrotron radiation induced total reflection X-ray fluorescence (SR-TXRF) acquisition was used to determine the oxidation state of Fe in human cancer cells and simultaneously their elemental composition by applying a simple sample preparation procedure consisting of pipetting the cell suspension onto the quartz reflectors. XANES spectra of several inorganic and organic iron compounds were recorded and compared to that of different cell lines. The XANES spectra of cells, independently from the phase of cell growth and cell type were very similar to that of ferritin, the main Fe store within the cell. The spectra obtained after CoCl2 or NiCl2 treatment, which could mimic a hypoxic state of cells, did not differ noticeably from that of the ferritin standard. After 5-fluorouracil administration, which could also induce an oxidative-stress in cells, the absorption edge position was shifted toward higher energies representing a higher oxidation state of Fe. Intense treatment with antimycin A, which inhibits electron transfer in the respiratory chain, resulted in minor changes in the spectrum, resembling rather the N-donor Fe-α,α'-dipyridyl complex at the oxidation energy of Fe(III), than ferritin. The incorporation of Co and Ni in the cells was followed by SR-TXRF measurements.

  9. Expression of the alternative oxidase mitigates beta-amyloid production and toxicity in model systems.

    Science.gov (United States)

    El-Khoury, Riyad; Kaulio, Eveliina; Lassila, Katariina A; Crowther, Damian C; Jacobs, Howard T; Rustin, Pierre

    2016-07-01

    Mitochondrial dysfunction has been widely associated with the pathology of Alzheimer's disease, but there is no consensus on whether it is a cause or consequence of disease, nor on the precise mechanism(s). We addressed these issues by testing the effects of expressing the alternative oxidase AOX from Ciona intestinalis, in different models of AD pathology. AOX can restore respiratory electron flow when the cytochrome segment of the mitochondrial respiratory chain is inhibited, supporting ATP synthesis, maintaining cellular redox homeostasis and mitigating excess superoxide production at respiratory complexes I and III. In human HEK293-derived cells, AOX expression decreased the production of beta-amyloid peptide resulting from antimycin inhibition of respiratory complex III. Because hydrogen peroxide was neither a direct product nor substrate of AOX, the ability of AOX to mimic antioxidants in this assay must be indirect. In addition, AOX expression was able to partially alleviate the short lifespan of Drosophila models neuronally expressing human beta-amyloid peptides, whilst abrogating the induction of markers of oxidative stress. Our findings support the idea of respiratory chain dysfunction and excess ROS production as both an early step and as a pathologically meaningful target in Alzheimer's disease pathogenesis, supporting the concept of a mitochondrial vicious cycle underlying the disease. PMID:27094492

  10. Assay of mitochondrial functions by resazurin in vitro

    Institute of Scientific and Technical Information of China (English)

    Hai-xia ZHANG; Guan-hua DU; Jun-tian ZHANG

    2004-01-01

    AIM: To study the mechanism of resazurin as indicator of mitochondrial function and to develop a rapid and sensitive assay for measuring metabolic activity of isolated mitochondria from rat liver in vitro. METHODS: The screening was carried out on 96-well microtitre plates by monitoring fluorescence intensity of resazurin reduced by mitochondria. Experimental conditions were optimized and influences of several inhibitors on mitochondrial function were observed. RESULTS: Fluorescence intensity increased in a linear manner when the mitochondrial protein concentration from 5 to 50 μg protein per well was incubated with resazurin (5 μmol/L) during 230 min period at 37 ℃. Edetic acid could promote the reduction of resazurin in mitochondria. The fluorescence intensity decreased greatly after pretreatment with NaN3, antimycin A, carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP),and oligomycin compared with the control. However, the typical complex I inhibitor, rotenone enhanced the fluorescence intensity without mitochondria. CONCLUSION: Using resazurin to determine mitochondrial function is sensitive, inexpensive and could be easily automated for high throughput screening.

  11. Putative Structural and Functional Coupling of the Mitochondrial BKCa Channel to the Respiratory Chain.

    Directory of Open Access Journals (Sweden)

    Piotr Bednarczyk

    Full Text Available Potassium channels have been found in the inner mitochondrial membranes of various cells. These channels regulate the mitochondrial membrane potential, the matrix volume and respiration. The activation of these channels is cytoprotective. In our study, the single-channel activity of a large-conductance Ca(2+-regulated potassium channel (mitoBKCa channel was measured by patch-clamping mitoplasts isolated from the human astrocytoma (glioblastoma U-87 MG cell line. A potassium-selective current was recorded with a mean conductance of 290 pS in symmetrical 150 mM KCl solution. The channel was activated by Ca(2+ at micromolar concentrations and by the potassium channel opener NS1619. The channel was inhibited by paxilline and iberiotoxin, known inhibitors of BKCa channels. Western blot analysis, immuno-gold electron microscopy, high-resolution immunofluorescence assays and polymerase chain reaction demonstrated the presence of the BKCa channel β4 subunit in the inner mitochondrial membrane of the human astrocytoma cells. We showed that substrates of the respiratory chain, such as NADH, succinate, and glutamate/malate, decrease the activity of the channel at positive voltages. This effect was abolished by rotenone, antimycin and cyanide, inhibitors of the respiratory chain. The putative interaction of the β4 subunit of mitoBKCa with cytochrome c oxidase was demonstrated using blue native electrophoresis. Our findings indicate possible structural and functional coupling of the mitoBKCa channel with the mitochondrial respiratory chain in human astrocytoma U-87 MG cells.

  12. Evaluation of the electron transport chain inhibition and uncoupling of mitochondrial bioelectrocatalysis with antibiotics and nitro-based compounds

    International Nuclear Information System (INIS)

    Mitochondrial bioelectrocatalysis can be useful for sensing applications due to the unique metabolic pathways than can be selectively inhibited and uncoupled in mitochondria. This paper details the comparison of different inhibitors and nitro-containing explosive uncouplers in a mitochondria-catalyzed biofuel cell for self-powered explosive sensing. Previous research has reported inhibition of pyruvate oxidation at a mitochondria-modified electrode followed by nitroaromatic uncoupling of current and power. We have previously used oligomycin as the antibiotic and nitrobenzene as the uncoupler of the membrane in the mitochondria-catalyzed biofuel cell, but no comprehensive comparison of various mitochondria inhibitors or explosives has been performed. Results are discussed here for inhibitors targeting complex I, complex III, ATP synthases, adenine nucleotide transport and monocarboxylic acid transport. Reactivation with nitrobenzene was possible in the presence of these inhibitors: oligomycin, 3,3'-diindolylmethane, atractyloside, rotenone, α-cyano-4-hydroxy cinnamic acid and antimycin A. All eleven explosives studied, including: 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), caused uncoupling of the mitochondria function and could be detected by the biosensor.

  13. Efflux of radioactive nucleotides from mouse pancreatic islets prelabelled with 2-3H-adenosine

    International Nuclear Information System (INIS)

    Cultured mouse pancreatic islets were prelabelled with 2-3H-adenosine in order to monitor the efflux pattern of radioactivity and insulin. The outflow of radioactivity decreased continuously when the islets were perifused with glucose (1.67 mmol/l). When raising the glucose concentration to 16.7 mmol/l, there was a prompt inhibition of the radioactive efflux concomitant with an increased rate of insulin release. These effects were reversed when the high glucose challenge was withdrawn. Similar radioactive efflux patterns were obtained after addition of α-ketoisocaproic acid, leucine or pyruvate to the perifusion medium, and also when the islets were challenged with high glucose concentrations in the absence of calcium. Both antimycin A and glipizide stimulated the efflux of radioactivity, although only the addition of glipizide was accompanied by a stimulation of the insulin release. Nucleotides constituted approximately 90% of the total effluent radioactivity. Decrease in the radioactive AMP and ADP efflux due to high glucose was furthermore found to be the cause of the observed inhibition of the total radioactive efflux. The changes in radioactive efflux induced by glucose probably reflect changes in the intracellular concentrations of AMP and ADP. It is concluded that no simple correlation exists between radioactive efflux and insulin release and that changes in the intracellular concentrations of nucleotides may be an early event in the stimulus-secretion coupling of glucose-induced insulin release. (orig.)

  14. Efflux of radioactive nucleotides from mouse pancreatic islets prelabelled with 2-/sup 3/H-adenosine

    Energy Technology Data Exchange (ETDEWEB)

    Welsh, M.

    1982-07-01

    Cultured mouse pancreatic islets were prelabelled with 2-/sup 3/H-adenosine in order to monitor the efflux pattern of radioactivity and insulin. The outflow of radioactivity decreased continuously when the islets were perifused with glucose (1.67 mmol/l). When raising the glucose concentration to 16.7 mmol/l, there was a prompt inhibition of the radioactive efflux concomitant with an increased rate of insulin release. These effects were reversed when the high glucose challenge was withdrawn. Similar radioactive efflux patterns were obtained after addition of ..cap alpha..-ketoisocaproic acid, leucine or pyruvate to the perifusion medium, and also when the islets were challenged with high glucose concentrations in the absence of calcium. Both antimycin A and glipizide stimulated the efflux of radioactivity, although only the addition of glipizide was accompanied by a stimulation of the insulin release. Nucleotides constituted approximately 90% of the total effluent radioactivity. Decrease in the radioactive AMP and ADP efflux due to high glucose was furthermore found to be the cause of the observed inhibition of the total radioactive efflux. The changes in radioactive efflux induced by glucose probably reflect changes in the intracellular concentrations of AMP and ADP. It is concluded that no simple correlation exists between radioactive efflux and insulin release and that changes in the intracellular concentrations of nucleotides may be an early event in the stimulus-secretion coupling of glucose-induced insulin release.

  15. Metabolic profiles show specific mitochondrial toxicities in vitro in myotube cells

    Energy Technology Data Exchange (ETDEWEB)

    Xu Qiuwei, E-mail: qiuwei_xu@merck.com; Vu, Heather; Liu Liping; Wang, Ting-Chuan; Schaefer, William H. [Merck Research Laboratories (United States)

    2011-04-15

    Mitochondrial toxicity has been a serious concern, not only in preclinical drug development but also in clinical trials. In mitochondria, there are several distinct metabolic processes including fatty acid {beta}-oxidation, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS), and each process contains discrete but often intimately linked steps. Interruption in any one of those steps can cause mitochondrial dysfunction. Detection of inhibition to OXPHOS can be complicated in vivo because intermediate endogenous metabolites can be recycled in situ or circulated systemically for metabolism in other organs or tissues. Commonly used assays for evaluating mitochondrial function are often applied to ex vivo or in vitro samples; they include various enzymatic or protein assays, as well as functional assays such as measurement of oxygen consumption rate, membrane potential, or acidification rates. Metabolomics provides quantitative profiles of overall metabolic changes that can aid in the unraveling of explicit biochemical details of mitochondrial inhibition while providing a holistic view and heuristic understanding of cellular bioenergetics. In this paper, we showed the application of quantitative NMR metabolomics to in vitro myotube cells treated with mitochondrial toxicants, rotenone and antimycin A. The close coupling of the TCA cycle to the electron transfer chain (ETC) in OXPHOS enables specific diagnoses of inhibition to ETC complexes by discrete biochemical changes in the TCA cycle.

  16. Calmodulin stimulation of calcium transport in carrot microsomal vesicles

    International Nuclear Information System (INIS)

    ATP-dependent 45Ca2+ uptake into microsomal vesicles isolated from cultured carrot cells (Daucus carota Danvers) was stimulated 2-3 fold by 5 ug/ml calmodulin (CaM). Microsomal vesicles separated with a linear sucrose gradient showed two peaks with CaM-stimulated Ca2+ uptake activities. One peak (at 1.12 g/cc) comigrated with the activity of the antimycin A-insensitive NADH-dependent cytochrome c reductase. This transport activity was enhanced 10-20 fold by 10 mM oxalate and appeared to be associates with vesicles derived primarily from the ER. The other peak of CaM-stimulated Ca2+ uptake (at 1.17 g/cc) was not affected by oxalate. These vesicles are probably derived from the plasma membrane. Preliminary experiments with the low-density vesicles (ER) vesicles, indicate that inositol-1,4,5-trisphosphate caused a transient reduction in intravesicular Ca2+. These results are consistent with the ER being an important site of intracellular Ca2+ regulation

  17. Binding of 125I-labeled endotoxin to bovine, canine, and equine platelets and endotoxin-induced agglutination of canine platelets

    International Nuclear Information System (INIS)

    Endotoxin from Escherichia coli O127:B8, Salmonella abortus-equi and S minnesota induced clumping of some canine platelets (PLT) at a final endotoxin concentration of 1 microgram/ml. Endotoxin-induced clumping of canine PLT was independent of PLT energy-requiring processes, because clumping was observed with canine PLT incubated with 2-deoxy-D-glucose and antimycin A. The PLT responded to adenosine diphosphate before, but not after, incubation with the metabolic inhibitors. Endotoxin induced a slight and inconsistant clumping of bovine and equine PLT at high (mg/ml) endotoxin concentration. High-affinity binding sites could not be demonstrated on canine, bovine, and equine PLT, using 125I-labeled E coli O127:B8 endotoxin. Nonspecific binding was observed and appeared to be due primarily to an extraneous coat on the PLT surface that was removed by gel filtration. The endotoxin that was bound to PLT did not appear to modify PLT function. An attempt to identify plasma proteins that bound physiologically relevant amounts of endotoxin was not successful. The significance of the endotoxin-induced clumping or lack of it on the pathophysiology of endotoxemia is discussed

  18. Toxicity of fishery chemicals to the asiatic clam, Corbicula manilensis

    Science.gov (United States)

    Chandler, Jack H.; Marking, L.L.

    1979-01-01

    The Asiatic clam (Corbicula manilensis), a species introduced into U. S. waters, has spread rapidly, and its ability to survive, reproduce, and spread has caused concern. Aquatic biologists suspect that the clams may crowd out indigenous mollusks, and the animals sometimes plug water intakes and leave shell deposits that interfere with sand and gravel operations. The toxicity of 20 commonly used fishery chemicals to the Asiatic clam was determined to evaluate hazards to a nontarget aquatic invertebrate and to assess the potential of the chemicals for controlling clam populations. Among six piscicides and two lampricides tested, antimycin was most toxic to the clam; the 96-h LC50 was 0.065 mg/L. Among three therapeutants and two disinfectants tested, nifurpirinol was the most toxic; the 96-h LC50 was 7.60 mg/L. All of the compounds were less toxic to the clam than to fish. As a nontarget organism, this clam would be safe in water treated with any of the tested fishery chemicals at recommended use pattern concentrations. None of the chemicals have potential for controlling unwanted populations of these clams.

  19. Metabolic profiles show specific mitochondrial toxicities in vitro in myotube cells

    International Nuclear Information System (INIS)

    Mitochondrial toxicity has been a serious concern, not only in preclinical drug development but also in clinical trials. In mitochondria, there are several distinct metabolic processes including fatty acid β-oxidation, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS), and each process contains discrete but often intimately linked steps. Interruption in any one of those steps can cause mitochondrial dysfunction. Detection of inhibition to OXPHOS can be complicated in vivo because intermediate endogenous metabolites can be recycled in situ or circulated systemically for metabolism in other organs or tissues. Commonly used assays for evaluating mitochondrial function are often applied to ex vivo or in vitro samples; they include various enzymatic or protein assays, as well as functional assays such as measurement of oxygen consumption rate, membrane potential, or acidification rates. Metabolomics provides quantitative profiles of overall metabolic changes that can aid in the unraveling of explicit biochemical details of mitochondrial inhibition while providing a holistic view and heuristic understanding of cellular bioenergetics. In this paper, we showed the application of quantitative NMR metabolomics to in vitro myotube cells treated with mitochondrial toxicants, rotenone and antimycin A. The close coupling of the TCA cycle to the electron transfer chain (ETC) in OXPHOS enables specific diagnoses of inhibition to ETC complexes by discrete biochemical changes in the TCA cycle.

  20. Role of mitochondria in spontaneous rhythmic activity and intracellular calcium waves in the guinea pig gallbladder smooth muscle.

    Science.gov (United States)

    Balemba, Onesmo B; Bartoo, Aaron C; Nelson, Mark T; Mawe, Gary M

    2008-02-01

    Mitochondrial Ca(2+) handling has been implicated in spontaneous rhythmic activity in smooth muscle and interstitial cells of Cajal. In this investigation we evaluated the effect of mitochondrial inhibitors on spontaneous action potentials (APs), Ca(2+) flashes, and Ca(2+) waves in gallbladder smooth muscle (GBSM). Disruption of the mitochondrial membrane potential with carbonyl cyanide 3-chlorophenylhydrazone, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone, rotenone, and antimycin A significantly reduced or eliminated APs, Ca(2+) flashes, and Ca(2+) waves in GBSM. Blockade of ATP production with oligomycin did not alter APs or Ca(2+) flashes but significantly reduced Ca(2+) wave frequency. Inhibition of mitochondrial Ca(2+) uptake and Ca(2+) release with Ru360 and CGP-37157, respectively, reduced the frequency of Ca(2+) flashes and Ca(2+) waves in GBSM. Similar to oligomycin, cyclosporin A did not alter AP and Ca(2+) flash frequency but significantly reduced Ca(2+) wave activity. These data suggest that mitochondrial Ca(2+) handling is necessary for the generation of spontaneous electrical activity and may therefore play an important role in gallbladder tone and motility. PMID:18048480

  1. Low-level laser therapy activates NF-kB via generation of reactive oxygen species in mouse embryonic fibroblasts.

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    Aaron C-H Chen

    Full Text Available BACKGROUND: Despite over forty years of investigation on low-level light therapy (LLLT, the fundamental mechanisms underlying photobiomodulation at a cellular level remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we isolated murine embryonic fibroblasts (MEF from transgenic NF-kB luciferase reporter mice and studied their response to 810 nm laser radiation. Significant activation of NF-kB was observed at fluences higher than 0.003 J/cm(2 and was confirmed by Western blot analysis. NF-kB was activated earlier (1 hour by LLLT compared to conventional lipopolysaccharide treatment. We also observed that LLLT induced intracellular reactive oxygen species (ROS production similar to mitochondrial inhibitors, such as antimycin A, rotenone and paraquat. Furthermore, we observed similar NF-kB activation with these mitochondrial inhibitors. These results, together with inhibition of laser induced NF-kB activation by antioxidants, suggests that ROS play an important role in the laser induced NF-kB signaling pathways. However, LLLT, unlike mitochondrial inhibitors, induced increased cellular ATP levels, which indicates that LLLT also upregulates mitochondrial respiration. CONCLUSION: We conclude that LLLT not only enhances mitochondrial respiration, but also activates the redox-sensitive NFkB signaling via generation of ROS. Expression of anti-apoptosis and pro-survival genes responsive to NFkB could explain many clinical effects of LLLT.

  2. Uncoupling protein-2 attenuates palmitoleate protection against the cytotoxic production of mitochondrial reactive oxygen species in INS-1E insulinoma cells

    Directory of Open Access Journals (Sweden)

    Jonathan Barlow

    2015-04-01

    Full Text Available High glucose and fatty acid levels impair pancreatic beta cell function. We have recently shown that palmitate-induced loss of INS-1E insulinoma cells is related to increased reactive oxygen species (ROS production as both toxic effects are prevented by palmitoleate. Here we show that palmitate-induced ROS are mostly mitochondrial: oxidation of MitoSOX, a mitochondria-targeted superoxide probe, is increased by palmitate, whilst oxidation of the equivalent non-targeted probe is unaffected. Moreover, mitochondrial respiratory inhibition with antimycin A stimulates palmitate-induced MitoSOX oxidation. We also show that palmitate does not change the level of mitochondrial uncoupling protein-2 (UCP2 and that UCP2 knockdown does not affect palmitate-induced MitoSOX oxidation. Palmitoleate does not influence MitoSOX oxidation in INS-1E cells ±UCP2 and largely prevents the palmitate-induced effects. Importantly, UCP2 knockdown amplifies the preventive effect of palmitoleate on palmitate-induced ROS. Consistently, viability effects of palmitate and palmitoleate are similar between cells ±UCP2, but UCP2 knockdown significantly augments the palmitoleate protection against palmitate-induced cell loss at high glucose. We conclude that UCP2 neither mediates palmitate-induced mitochondrial ROS generation and the associated cell loss, nor protects against these deleterious effects. Instead, UCP2 dampens palmitoleate protection against palmitate toxicity.

  3. Low-Level Laser Therapy Activates NF-kB via Generation of Reactive Oxygen Species in Mouse Embryonic Fibroblasts

    Science.gov (United States)

    Huang, Ying-Ying; Tomkinson, Elizabeth M.; Sharma, Sulbha K.; Kharkwal, Gitika B.; Saleem, Taimur; Mooney, David; Yull, Fiona E.; Blackwell, Timothy S.; Hamblin, Michael R.

    2011-01-01

    Background Despite over forty years of investigation on low-level light therapy (LLLT), the fundamental mechanisms underlying photobiomodulation at a cellular level remain unclear. Methodology/Principal Findings In this study, we isolated murine embryonic fibroblasts (MEF) from transgenic NF-kB luciferase reporter mice and studied their response to 810 nm laser radiation. Significant activation of NF-kB was observed at fluences higher than 0.003 J/cm2 and was confirmed by Western blot analysis. NF-kB was activated earlier (1 hour) by LLLT compared to conventional lipopolysaccharide treatment. We also observed that LLLT induced intracellular reactive oxygen species (ROS) production similar to mitochondrial inhibitors, such as antimycin A, rotenone and paraquat. Furthermore, we observed similar NF-kB activation with these mitochondrial inhibitors. These results, together with inhibition of laser induced NF-kB activation by antioxidants, suggests that ROS play an important role in the laser induced NF-kB signaling pathways. However, LLLT, unlike mitochondrial inhibitors, induced increased cellular ATP levels, which indicates that LLLT also upregulates mitochondrial respiration. Conclusion We conclude that LLLT not only enhances mitochondrial respiration, but also activates the redox-sensitive NFkB signaling via generation of ROS. Expression of anti-apoptosis and pro-survival genes responsive to NFkB could explain many clinical effects of LLLT. PMID:21814580

  4. The localization of glycollate-pathway enzymes in Euglena.

    Science.gov (United States)

    Collins, N; Merrett, M J

    1975-05-01

    Isolation of organelles from broken-cell suspensions of phototrophically grown Euglena gracilis Klebs was achieved by isopycnic centrifugation on sucrose gradients. 2. Equilibrium densities of 1.23g/cm3 for peroxisome-like particles, 1.22g/cm3 for mitochondria and 1.17g/cm3 for chloroplasts were recorded. 3. The enzymes glycollate dehydrogenase, glutamate-glyoxylate aminotransferase, serineglyoxylate aminotransferase, aspartate-alpha-oxoglutarate aminotransferase, hydroxy pyruvate reductase and malate dehydrogenase were present in peroxisome-like particles. 4. Unlike higher plants glycollate dehydrogenase and glutamate-glyoxylate aminotransferase were present in the mitochondria of Euglena. 5. Rates of glycollate and D-lactate oxidation were additive in the mitochondria, and, although glycollate dehydrogenase was inhibited by cyanide, D-lactate dehydrogenase activity was unaffected. 6. Glycollate oxidation was linked to O2 uptake in mitochondria but not in peroxisome-like particles. This glycollate-dependent O2 uptake was inhibited by antimycin A or cyanide. 7. The physiological significance of glycollate metabolism in Euglena mitochondria is discussed, with special reference to its role in photorespiration in algae. PMID:1156408

  5. In vivo phospholipid biosynthesis in cotton cotyledons during glyoxysome enlargement

    International Nuclear Information System (INIS)

    The surface are of cottonseed glyoxysomes increases about 4 fold within 36 h after imbibition. Membrane phospholipid must become available to glyoxysomes to accommodate expansion. Incubation of cotyledons (18-h-old) in 14C-choline (1 h) resulted in at least 85% recovery of 14C-phosphatidylcholine (PC) in membranes comigrating on sucrose gradients (20-59% w/w) with antimycin A-insensitive cytochrome c reductase (CCR) activity and choline- and ethanolaminephosphotransferase (CPT and EPT) activities (ER at about 24% w/w sucrose). Chase experiments with 3.4 M choline chloride for 2, 12, or 24 h led to increasing proportions of 14C-PC (36% after 24 h) recovery in mitochondria. No transfer of 14C-PC to enlarging glyoxysomes was detected. Incubations in 14C-ethanolamine yielded ER labeling after only 30 min. 14C-PE chased into mitochondria membranes more rapidly than PC (45% after 12 h), and no 14C-PE chased into glyoxysome membranes. Evidence for synthesis of 14C-PC from 14C-PE was found after 12 h chase with 1 M ethanolamine hydrochloride. Our results indicate that ER is the primary site of PC and PE synthesis in vivo and that ER contributes newly synthesized PC and PE to mitochondrial membranes but not to expanding glyoxysomal membranes. This is different from membrane biogenesis of glyoxysomes proliferating in castor bean endosperm

  6. Natural Resistance to Inhibitors of the Ubiquinol Cytochrome c Oxidoreductase of Rubrivivax gelatinosus: Sequence and Functional Analysis of the Cytochrome bc1 Complex

    Science.gov (United States)

    Ouchane, Soufian; Agalidis, Ileana; Astier, Chantal

    2002-01-01

    Biochemical analyses of Rubrivivax gelatinosus membranes have revealed that the cytochrome bc1 complex is highly resistant to classical inhibitors including myxothiazol, stigmatellin, and antimycin. This is the first report of a strain exhibiting resistance to inhibitors of both catalytic Q0 and Qi sites. Because the resistance to cytochrome bc1 inhibitors is primarily related to the cytochrome b primary structure, the petABC operon encoding the subunits of the cytochrome bc1 complex of Rubrivivax gelatinosus was sequenced. In addition to homologies to the corresponding proteins from other organisms, the deduced amino acid sequence of the cytochrome b polypeptide shows (i) an E303V substitution in the highly conserved PEWY loop involved in quinol/stigmatellin binding, (ii) other substitutions that could be involved in resistance to cytochrome bc1 inhibitors, and (iii) 14 residues instead of 13 between the histidines in helix IV that likely serve as the second axial ligand to the bH and bL hemes, respectively. These characteristics imply different functional properties of the cytochrome bc1 complex of this bacterium. The consequences of these structural features for the resistance to inhibitors and for the properties of R. gelatinosus cytochrome bc1 are discussed with reference to the structure and function of the cytochrome bc1 complexes from other organisms. PMID:12081951

  7. Occurrence of the malate-aspartate shuttle in various tumor types.

    Science.gov (United States)

    Greenhouse, W V; Lehninger, A L

    1976-04-01

    The activity of the malate-aspartate shuttle for the reoxidation of cytoplasmic reduced nicotinamide adenine dinucleotide (NADH) by mitochondria was assessed in six lines of rodent ascites tumor cells (two strains of Ehrlich ascites carcinoma, Krebs II carcinoma, Novikoff hepatoma, AS-30D hepatoma, and L1210 mouse leukemia). All the tumor cells examined showed mitochondrial reoxidation of cytoplasmic NADH, as evidenced by the accumulation of pyruvate when the cells were incubated aerobically with L-lactate. Reoxidation of cytoplasmic NADH thus generated was completely inhibited by the transaminase inhibitor aminooxyacetate. The involvement of the respiratory chain in the reoxidation of cytoplasmic NADH was demonstrated by the action of cyanide, rotenone, and antimycin A, which strongly inhibited the formation of pyruvate from added L-lactate. Compounds that inhibit the carrier-mediated entry of malate into mitochondria, such as butylmalonate, benzenetricarboxylate, and iodobenzylmalonate, also inhibited the accumulation of pyruvate from added L-lactate by the tumor cells. The maximal rate of the malate-aspartate shuttle was established by addtion of arsenite to inhibit the mitochondrial oxidation of the pyruvate formed from added lactate. The capacity of the various tumor lines for the reoxidation of cytoplasmic NADH via the malate-aspartate shuttle approaches 20% of the total respiratory rate of the cells and thus appears to be sufficient to account for the mitochondrial reoxidation of that fraction of glycolytic NADH not reoxidized by pyruvate and lactate dehydrognenase in the cytoplasm. PMID:177206

  8. Photosystem I and photophosphorylation-dependent leucine incorporation in the blue-green alga

    International Nuclear Information System (INIS)

    sub(L)-Leucine uptake and incorporation in the blue-green alga Anacystis nidulans were measured during illumination with monochromatic light of 630 and 717 nm. With near as well as far red light, an enhanced uptake of 14C-sub(L)-leucine was observed. In far red light, the leucine uptake depended on light intensity and pH value. After the first few minutes, the uptake remained constant for more than one hour. The rate of uptake in light was the same in air as in nitrogen. The incorporation of 14C-leucine in the soluble fraction decreased in the presence of chloramphenicol which prevents protein synthesis. In far red light, its incorporation was insensitive to DCMU (5 x 10-6 M) but was depressed by uncouplers like CCCP or desaspidin. These effects are taken as evidence that leucine incorporation under the conditions used is dependent on photosystem I reactions and cyclic photophosphorylation. DBMIB and KCN in high concentrations decrease the leucine incorporation in far red light and indicate that plastoquinone and plastocyanin are members of the cyclic electron flow also in intact cells of Anacystis. Antimycin A has no inhibitory effect. The inhibition by other less specific inhibitors like salicylaldoxime, desaspidin and DSPD is discussed. (author)

  9. Effect of Hexavalent Chromium on Electron Leakage of Respiratory Chain in Mitochondria Isolated from Rat Liver

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    Ying Xie

    2013-03-01

    Full Text Available Background/Aims: In the present study, we explored reactive axygen species (ROS production in mitochondria, the mechanism of hexavalent chromium (Cr(VI hepatotoxicity, and the role of protection by GSH. Methods: Intact mitochondria were isolated from rat liver tissues and mitochondrial basal respiratory rates of NADH and FADH2 respiratory chains were determined. Mitochondria were treated with Cr(VI, GSH and several complex inhibitors. Mitochondria energized by glutamate/malate were separately or jointly treated with Rotenone (Rot, diphenyleneiodonium (DPI and antimycinA (Ant, while mitochondria energized by succinate were separately or jointly treated with Rot, DPI ‚ thenoyltrifluoroacetone (TTFA and Ant. Results: Cr(VI concentration-dependently induced ROS production in the NADH and FADH2 respiratory chain in liver mitochondria. Basal respiratory rate of the mitochondrial FADH2 respiratory chain was significantly higher than that of NADH respiratory chain. Hepatic mitochondrial electron leakage induced by Cr(VI from NADH respiratory chain were mainly from ubiquinone binding sites of complex I and complex III. Conclusion: Treatment with 50µM Cr(VI enhances forward movement of electrons through FADH2 respiratory chain and leaking through the ubiquinone binding site of complex III. Moreover, the protective effect of GSH on liver mitochondria electron leakage is through removing excess H2O2 and reducing total ROS.

  10. On the thyroid hormone-induced increase in respiratory capacity of isolated rat hepatocytes.

    Science.gov (United States)

    Gregory, R B; Berry, M N

    1991-12-01

    The respiratory capacities of hepatocytes, derived from hypothyroid, euthyroid and hyperthyroid rats, have been compared by measuring rates of oxygen uptake and by titrating components of the respiratory chain with specific inhibitors. Thyroid hormone increased the maximal rate of substrate-stimulated respiration and also increased the degree of ionophore-stimulated oxygen uptake. In titration experiments, similar concentrations of oligomycin or antimycin were required for maximal inhibition of respiration regardless of thyroid state, suggesting that the changes in respiratory capacity were not the result of variation in the amounts of ATP synthase or cytochrome b. However, less rotenone was required for maximal inhibition of respiration in the hypothyroid state than in cells from euthyroid or hyperthyroid rats, implying that hepatocytes from hypothyroid animals contain less NADH dehydrogenase. The concentration of carboxyatractyloside necessary for maximal inhibition of respiration was 100 microM in hepatocytes from hypothyroid rats, but 200 microM and 300 microM in hepatocytes from euthyroid and hyperthyroid rats, respectively, indicating a possible correlation between levels of thyroid hormone and the amount or activity of adenine nucleotide translocase. The increased capacity for coupled respiration in response to thyroid hormone is not associated with an increase in the components of the electron transport chain or ATP synthase, but correlates with an increased activity of adenine nucleotide translocase. PMID:1751550

  11. Similar Transition States Mediate the Q-cycle and Superoxide Production by the Cytochrome bc1 Complex

    International Nuclear Information System (INIS)

    The cytochrome bc complexes found in mitochondria, chloroplasts and many bacteria catalyze a critical reaction in their respective electron transport chains. The quinol oxidase (Qo) site in this complex oxidizes a hydroquinone (quinol), reducing two one-electron carriers, a low-potential cytochrome b heme and a ''Rieske'' iron-sulfur cluster. The overall electron transfer reactions are coupled to transmembrane translocation of protons via a ''Q-cycle'' mechanism, which generates proton motive force for ATP synthesis. Since semiquinone intermediates of quinol oxidation are generally highly reactive, one of the key questions in this field is: how does the Qo site oxidize quinol without the production of deleterious side reactions including superoxide production? We attempt to test three possible general models to account for this behavior: (1) The Qo site semiquinone (or quinol:imidazolate complex) is unstable and thus occurs at a very low steady-state concentration, limiting O2 reduction; (2) the Qo site semiquinone is highly stabilized making it unreactive towards oxygen; and (3) the Qo site catalyzes a quantum mechanically-coupled two-electron/two proton transfer without a semiquinone intermediate. Enthalpies of activation were found to be almost identical between the uninhibited Q-cycle and superoxide production in the presence of Antimycin A in wild type. This behavior was also preserved in a series of mutants with altered driving forces for quinol oxidation. Overall, the data supports models where the rate-limiting step for both Q-cycle and superoxide production are essentially identical, consistent with model 1 but requiring modifications to models 2 and 3

  12. GENE TRANSFER IN TOBACCO MITOCHONDRIA IN VITRO AND IN VIVO

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    Katyshev A.I.

    2012-08-01

    -cob* genetic construct with integrative properties. It contains the selective gene and the gene of interest under control of the 5'-regulatory regions of Arabidopsis orf262 gene and the tobacco cob gene. We used modified variant of the tobacco apocytochrome b gene as a gene for selection with the nucleotide substitution G128T (G43V which results in antimycin A resistance. The maize sod3.1 gene was used as a gene of interest. The construct was delivered into tobacco callus cells and leaf disks by biolistic method. The callus lines demonstrating the high growth rates in the presence of antimycin A in comparison with the non-transformed control lines were selected. PCR analysis of transformed callus lines revealed the presence of heterologous maize sod3.1 sequence and the integration of the construct elements in tobacco mitochondrial genome.

  13. Cytotoxic mechanisms of Zn2+ and Cd2+ involve Na+/H+ exchanger (NHE) activation by ROS

    International Nuclear Information System (INIS)

    The signaling mechanism induced by cadmium (Cd) and zinc (Zn) in gill cells of Mytilus galloprovincialis was investigated. Both metals cause an increase in ·O2- production, with Cd to be more potent (216 ± 15%) than Zn (150 ± 9.5%), in relation to control value (100%). The metals effect was reversed after incubation with the amiloride analogue, EIPA, a selective Na+/H+ exchanger (NHE) inhibitor as well as in the presence of calphostin C, a protein kinase C (PKC) inhibitor. The heavy metals effect on ·O2- production was mediated via the interaction of metal ions with α1- and β-adrenergic receptors, as shown after incubation with their respective agonists and antagonists. In addition, both metals caused an increase in intracellular pH (pHi) of gill cells. EIPA together with either metal significantly reduced the effect of each metal treatment on pHi. Incubation of gill cells with the oxidants rotenone, antimycin A and pyruvate caused a significant increase in pHi (ΔpHi 0.830, 0.272 and 0.610, respectively), while in the presence of the anti-oxidant N-acetyl cysteine (NAC) a decrease in pHi (ΔpHi -0.090) was measured, indicating that change in reactive oxygen species (ROS) production by heavy metals affects NHE activity. When rosiglitazone was incubated together with either heavy metal a decrease in O2- production was observed. Our results show a key role of NHE in the signal transduction pathway induced by Zn and Cd in gill cells, with the involvement of ROS, PKC, adrenergic and PPAR-γ receptors. In addition, differences between the two metals concerning NHE activation, O2- production and interaction with adrenergic receptors were observed

  14. Cytotoxic mechanisms of Zn{sup 2+} and Cd{sup 2+} involve Na{sup +}/H{sup +} exchanger (NHE) activation by ROS

    Energy Technology Data Exchange (ETDEWEB)

    Koutsogiannaki, Sophia [Laboratory of Animal Physiology, Zoology Department, School of Biology, Faculty of Science, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Evangelinos, Nikolaos [Laboratory of Animal Physiology, Zoology Department, School of Biology, Faculty of Science, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Koliakos, George [Department of Biological Chemistry, Medical School, Aristotle University of Thessaloniki, P.O. Box 17034, 54124 Thessaloniki (Greece); Kaloyianni, Martha [Laboratory of Animal Physiology, Zoology Department, School of Biology, Faculty of Science, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)]. E-mail: kaloyian@bio.auth.gr

    2006-07-20

    The signaling mechanism induced by cadmium (Cd) and zinc (Zn) in gill cells of Mytilus galloprovincialis was investigated. Both metals cause an increase in {center_dot}O{sub 2} {sup -} production, with Cd to be more potent (216 {+-} 15%) than Zn (150 {+-} 9.5%), in relation to control value (100%). The metals effect was reversed after incubation with the amiloride analogue, EIPA, a selective Na{sup +}/H{sup +} exchanger (NHE) inhibitor as well as in the presence of calphostin C, a protein kinase C (PKC) inhibitor. The heavy metals effect on {center_dot}O{sub 2} {sup -} production was mediated via the interaction of metal ions with {alpha}{sub 1}- and {beta}-adrenergic receptors, as shown after incubation with their respective agonists and antagonists. In addition, both metals caused an increase in intracellular pH (pHi) of gill cells. EIPA together with either metal significantly reduced the effect of each metal treatment on pHi. Incubation of gill cells with the oxidants rotenone, antimycin A and pyruvate caused a significant increase in pHi ({delta}pHi 0.830, 0.272 and 0.610, respectively), while in the presence of the anti-oxidant N-acetyl cysteine (NAC) a decrease in pHi ({delta}pHi -0.090) was measured, indicating that change in reactive oxygen species (ROS) production by heavy metals affects NHE activity. When rosiglitazone was incubated together with either heavy metal a decrease in O{sub 2} {sup -} production was observed. Our results show a key role of NHE in the signal transduction pathway induced by Zn and Cd in gill cells, with the involvement of ROS, PKC, adrenergic and PPAR-{gamma} receptors. In addition, differences between the two metals concerning NHE activation, O{sub 2} {sup -} production and interaction with adrenergic receptors were observed.

  15. Regulation of FOXOs and p53 by SIRT1 modulators under oxidative stress.

    Directory of Open Access Journals (Sweden)

    Yusuke S Hori

    Full Text Available Excessive reactive oxygen species (ROS induce apoptosis and are associated with various diseases and with aging. SIRT1 (sirtuin-1, an NAD+-dependent protein deacetylase, decreases ROS levels and participates in cell survival under oxidative stress conditions. SIRT1 modulates the transcription factors p53, a tumor suppressor and inducer of apoptosis, and the forkhead O (FOXO family, both of which play roles for cell survival and cell death. In this study, we aimed to know which is working greatly among p53 and FOXOs transcription factors in SIRT1's cell protective functions under oxidative stress conditions. The antimycin A-induced increase in ROS levels and apoptosis was enhanced by SIRT1 inhibitors nicotinamide and splitomicin, whereas it was suppressed by a SIRT1 activator, resveratrol, and a SIRT1 cofactor, NAD+. SIRT1-siRNA abolished the effects of splitomicin and resveratrol. p53-knockdown experiment in C2C12 cells and experiment using p53-deficient HCT116 cells showed that splitomicin and resveratrol modulated apoptosis by p53-dependent and p53-independent pathways. In p53-independent cell protective pathway, we found that FOXO1, FOXO3a, and FOXO4 were involved in SOD2's upregulation by resveratrol. The knockdown of these three FOXOs by siRNAs completely abolished the SOD2 induction, ROS reduction, and anti-apoptotic function of resveratrol. Our results indicate that FOXO1, FOXO3a and FOXO4, are indispensable for SIRT1-dependent cell survival against oxidative stress, although deacetylation of p53 has also some role for cell protective function of SIRT1.

  16. The metabolism of malate by cultured rat brain astrocytes

    International Nuclear Information System (INIS)

    Since malate is known to play an important role in a variety of functions in the brain including energy metabolism, the transfer of reducing equivalents and possibly metabolic trafficking between different cell types; a series of biochemical determinations were initiated to evaluate the rate of 14CO2 production from L-[U-14C]malate in rat brain astrocytes. The 14CO2 production from labeled malate was almost totally suppressed by the metabolic inhibitors rotenone and antimycin A suggesting that most of malate metabolism was coupled to the electron transport system. A double reciprocal plot of the 14CO2 production from the metabolism of labeled malate revealed biphasic kinetics with two apparent Km and Vmax values suggesting the presence of more than one mechanism of malate metabolism in these cells. Subsequent experiments were carried out using 0.01 mM and 0.5 mM malate to determine whether the addition of effectors would differentially alter the metabolism of high and low concentrations of malate. Effectors studied included compounds which could be endogenous regulators of malate metabolism and metabolic inhibitors which would provide information regarding the mechanisms regulating malate metabolism. Both lactate and aspartate decreased 14CO2 production from malate equally. However, a number of effectors were identified which selectively altered the metabolism of 0.01 mM malate including aminooxyacetate, furosemide, N-acetylaspartate, oxaloacetate, pyruvate and glucose, but had little or no effect on the metabolism of 0.5 mM malate. In addition, alpha-ketoglutarate and succinate decreased 14CO2 production from 0.01 mM malate much more than from 0.5 mM malate. In contrast, a number of effectors altered the metabolism of 0.5 mM malate more than 0.01 mM. These included methionine sulfoximine, glutamate, malonate, alpha-cyano-4-hydroxycinnamate and ouabain

  17. Mitochondrial dysfunction leads to impairment of insulin sensitivity and adiponectin secretion in adipocytes.

    Science.gov (United States)

    Wang, Chih-Hao; Wang, Ching-Chu; Huang, Hsin-Chang; Wei, Yau-Huei

    2013-02-01

    Adipocytes play an integrative role in the regulation of energy metabolism and glucose homeostasis in the human body. Functional defects in adipocytes may cause systemic disturbance of glucose homeostasis. Recent studies revealed mitochondrial abnormalities in the adipose tissue of patients with type 2 diabetes. In addition, patients with mitochondrial diseases usually manifest systemic metabolic disorder. However, it is unclear how mitochondrial dysfunction in adipocytes affects the regulation of glucose homeostasis. In this study, we induced mitochondrial dysfunction and overproduction of reactive oxygen species (ROS) by addition of respiratory inhibitors oligomycin A and antimycin A and by knockdown of mitochondrial transcription factor A (mtTFA), respectively. We found an attenuation of the insulin response as indicated by lower glucose uptake and decreased phosphorylation of Akt upon insulin stimulation of adipocytes with mitochondrial dysfunction. Furthermore, the expression of glucose transporter 4 (Glut4) and secretion of adiponectin were decreased in adipocytes with increased ROS generated by defective mitochondria. Moreover, the severity of insulin insensitivity was correlated with the extent of mitochondrial dysfunction. These results suggest that higher intracellular ROS levels elicited by mitochondrial dysfunction resulted in impairment of the function of adipocytes in the maintenance of glucose homeostasis through attenuation of insulin signaling, downregulation of Glut4 expression, and decrease in adiponectin secretion. Our findings substantiate the important role of mitochondria in the regulation of glucose homeostasis in adipocytes and also provide a molecular basis for the explanation of the manifestation of diabetes mellitus or insulin insensitivity in a portion of patients with mitochondrial diseases such as MELAS or MERRF syndrome. PMID:23253816

  18. Binding of fluorescent lanthanides to rat liver mitochondrial membranes and calcium ion-binding proteins.

    Science.gov (United States)

    Mikkelsen, R B; Wallach, D F

    1976-05-21

    (1) Tb3+ binding to mitochondrial membranes can be monitored by enhanced ion fluorescence at 545 nm with excitation at 285 nm. At low protein concentrations (less than 30 mug/ml) no inner filter effects are observed. (2) This binding is localized at the external surface of the inner membrane and is unaffected by inhibitors of respiration or oxidative phosphorylation. (3) A soluble Ca2+ binding protein isolated according to Lehninger, A.L. ((1971) Biochem. Biophys. Res. Commun. 42, 312-317) also binds Tb3+ with enhanced ion fluorescence upon excitation at 285 nm. The excitation spectrum of the isolated protein and of the intact mitochondria are indicative of an aromatic amino acid at the cation binding site. (4) Further characterization of the Tb3+-protein interaction revealed that there is more than one binding site per protein molecule and that these sites are clustered (less than 20 A). Neuraminidase treatment or organic solvent extraction of the protein did not affect fluorescent Tb3+ binding. (5) pH dependency studies of Tb3+ binding to the isolated protein or intact mitochondria demonstrated the importance of an ionizable group of pK greater than 6. At pH less than 7.5 the amount of Tb3+ bound to the isolated protein decreased with increase in pH as monitored by Tb3+ fluorescence. With intact mitochondria the opposite occurred with a large increase in Tb3+ fluorescence at higher pH. This increase was not observed when the mitochondria were preincubated with antimycin A and rotenone. PMID:6061

  19. Inhibition of the mitochondrial respiratory chain function abrogates quartz induced DNA damage in lung epithelial cells

    International Nuclear Information System (INIS)

    Respirable quartz dust has been classified as a human carcinogen by the International Agency for Research on Cancer. The aim of our study was to investigate the mechanisms of DNA damage by DQ12 quartz in RLE-6TN rat lung epithelial type II cells (RLE). Transmission electron microscopy and flow-cytometry analysis showed a rapid particle uptake (30 min to 4 h) of quartz by the RLE cells, but particles were not found within the cell nuclei. This suggests that DNA strand breakage and induction of 8-hydroxydeoxyguanosine - as also observed in these cells during these treatment intervals - did not result from direct physical interactions between particles and DNA, or from short-lived particle surface-derived reactive oxygen species. DNA damage by quartz was significantly reduced in the presence of the mitochondrial inhibitors rotenone and antimycin-A. In the absence of quartz, these inhibitors did not affect DNA damage, but they reduced cellular oxygen consumption. No signs of apoptosis were observed by quartz. Flow-cytometry analysis indicated that the reduced DNA damage by rotenone was not due to a possible mitochondria-mediated reduction of particle uptake by the RLE cells. Further proof of concept for the role of mitochondria was shown by the failure of quartz to elicit DNA damage in mitochondria-depleted 143B (rho-0) osteosarcoma cells, at concentrations where it elicited DNA damage in the parental 143B cell line. In conclusion, our data show that respirable quartz particles can elicit oxidative DNA damage in vitro without entering the nuclei of type II cells, which are considered to be important target cells in quartz carcinogenesis. Furthermore, our observations indicate that such indirect DNA damage involves the mitochondrial electron transport chain function, by an as-yet-to-be elucidated mechanism

  20. The energy blockers 3-bromopyruvate and lonidamine: effects on bioenergetics of brain mitochondria.

    Science.gov (United States)

    Macchioni, Lara; Davidescu, Magdalena; Roberti, Rita; Corazzi, Lanfranco

    2014-10-01

    Tumor cells favor abnormal energy production via aerobic glycolysis and show resistance to apoptosis, suggesting the involvement of mitochondrial dysfunction. The differences between normal and cancer cells in their energy metabolism provide a biochemical basis for developing new therapeutic strategies. The energy blocker 3-bromopyruvate (3BP) can eradicate liver cancer in animals without associated toxicity, and is a potent anticancer towards glioblastoma cells. Since mitochondria are 3BP targets, in this work the effects of 3BP on the bioenergetics of normal rat brain mitochondria were investigated in vitro, in comparison with the anticancer agent lonidamine (LND). Whereas LND impaired oxygen consumption dependent on any complex of the respiratory chain, 3BP was inhibitory to malate/pyruvate and succinate (Complexes I and II), but preserved respiration from glycerol-3-phosphate and ascorbate (Complex IV). Accordingly, although electron flow along the respiratory chain and ATP levels were decreased by 3BP in malate/pyruvate- and succinate-fed mitochondria, they were not significantly influenced from glycerol-3-phosphate- or ascorbate-fed mitochondria. LND produced a decrease in electron flow from all substrates tested. No ROS were produced from any substrate, with the exception of 3BP-induced H(2)O(2) release from succinate, which suggests an antimycin-like action of 3BP as an inhibitor of Complex III. We can conclude that 3BP does not abolish completely respiration and ATP synthesis in brain mitochondria, and has a limited effect on ROS production, confirming that this drug may have limited harmful effects on normal cells. PMID:25194986

  1. ATP generation in Leishmania donovani amastigote form

    Directory of Open Access Journals (Sweden)

    Anup Kumar Roy

    2013-06-01

    Full Text Available Leishmania is the causative agent of various forms of leishmaniasis, a significant cause of morbidity and mortality. The clinical manifestations of the disease range from selfhealing cutaneous and mucocutaneous skin ulcers to a fatal visceral form named visceral leishmaniasis or kala-azar. The differentiation of Leishmania parasites from the insect stage, the promastigote, towards the pathogenic mammalian stage, the amastigote, is triggered primarily by the rise in ambient temperature encountered during the insect to mammal transmission. The survival of amastigote stage is dependent on that of the host. Regarding energy metabolism, which is an essential factor for the survival, parasites adapt to the environment under low oxygen tension in the host using metabolic systems which are very different from that of the host mammals. The amastigote form of L. donovani is independent on oxidative phosphorylation for ATP production. Indeed, its cell growth was not inhibited by 20-fold excess oligomycin and dicyclohexylcarbodiimide, which are the most specific inhibitors of the mitochondrial FoF1-ATP synthase. In contrast, mitochondrial complex I inhibitor rotenone and complex III inhibitor antimycin A inhibited amastigote cell growth, suggesting the role of complex I and complex III in cell survival. Complex II appeared to have no role in cell survival. To further investigate the site of ATP production, we studied the substrate level phosphorylation, which was involved in the synthesis of ATP. Succinate-pyruvate couple showed the highest substrate level phosphorylation, whereas NADHfumarate and NADH-pyruvate couples failed to produce ATP. In contrast, NADPH-fumarate showed the highest rate of ATP formation in promastigotes. We conclude that substrate level phosphorylation is essential for the growth of L. donovani amastigotes.

  2. The upper and lower limits of the mechanistic stoichiometry of mitochondrial oxidative phosphorylation. Stoichiometry of oxidative phosphorylation.

    Science.gov (United States)

    Beavis, A D; Lehninger, A L

    1986-07-15

    Determination of the intrinsic or mechanistic P/O ratio of oxidative phosphorylation is difficult because of the unknown magnitude of leak fluxes. Applying a new approach developed to overcome this problem (see our preceding paper in this journal), the relationships between the rate of O2 uptake [( Jo)3], the net rate of phosphorylation (Jp), the P/O ratio, and the respiratory control ratio (RCR) have been determined in rat liver mitochondria when the rate of phosphorylation was systematically varied by three specific means. (a) When phosphorylation is titrated with carboxyatractyloside, linear relationships are observed between Jp and (Jo)3. These data indicate that the upper limit of the mechanistic P/O ratio is 1.80 for succinate and 2.90 for 3-hydroxybutyrate oxidation. (b) Titration with malonate or antimycin yields linear relationships between Jp and (Jo)3. These data give the lower limit of the mechanistic P/O ratio of 1.63 for succinate and 2.66 for 3-hydroxybutyrate oxidation. (c) Titration with a protonophore yields linear relationships between Jp, (Jo)3, and (Jo)4 and between P/O and 1/RCR. Extrapolation of the P/O ratio to 1/RCR = 0 yields P/O ratios of 1.75 for succinate and 2.73 for 3-hydroxybutyrate oxidation which must be equal to or greater than the mechanistic stoichiometry. When published values for the H+/O and H+/ATP ejection ratios are taken into consideration, these measurements suggest that the mechanistic P/O ratio is 1.75 for succinate oxidation and 2.75 for NADH oxidation. PMID:3015613

  3. Quiescence in Artemia franciscana embryos: reversible arrest of metabolism and gene expression at low oxygen levels.

    Science.gov (United States)

    Hand, S C

    1998-04-01

    evidence from experiments with nigericin indicates that mitochondrial protein synthesis is depressed directly by acidification of matrix pH. The oxygen dependency of organellar protein synthesis is not explained by blockage of the electron transport chain or by the increased redox state. Rather, this cyanide- and antimycin-insensitive, but hypoxia-sensitive, inhibitory signature for the arrest of protein synthesis suggests the presence of a molecular oxygen sensor within the mitochondrion. PMID:9510534

  4. Hypoxic vasoconstriction of partial muscular intra-acinar pulmonary arteries in murine precision cut lung slices

    Directory of Open Access Journals (Sweden)

    Goldenberg Anna

    2006-06-01

    Full Text Available Abstract Background Acute alveolar hypoxia causes pulmonary vasoconstriction (HPV which serves to match lung perfusion to ventilation. The underlying mechanisms are not fully resolved yet. The major vascular segment contributing to HPV, the intra-acinar artery, is mostly located in that part of the lung that cannot be selectively reached by the presently available techniques, e.g. hemodynamic studies of isolated perfused lungs, recordings from dissected proximal arterial segments or analysis of subpleural vessels. The aim of the present study was to establish a model which allows the investigation of HPV and its underlying mechanisms in small intra-acinar arteries. Methods Intra-acinar arteries of the mouse lung were studied in 200 μm thick precision-cut lung slices (PCLS. The organisation of the muscle coat of these vessels was characterized by α-smooth muscle actin immunohistochemistry. Basic features of intra-acinar HPV were characterized, and then the impact of reactive oxygen species (ROS scavengers, inhibitors of the respiratory chain and Krebs cycle metabolites was analysed. Results Intra-acinar arteries are equipped with a discontinuous spiral of α-smooth muscle actin-immunoreactive cells. They exhibit a monophasic HPV (medium gassed with 1% O2 that started to fade after 40 min and was lost after 80 min. This HPV, but not vasoconstriction induced by the thromboxane analogue U46619, was effectively blocked by nitro blue tetrazolium and diphenyleniodonium, indicating the involvement of ROS and flavoproteins. Inhibition of mitochondrial complexes II (3-nitropropionic acid, thenoyltrifluoroacetone and III (antimycin A specifically interfered with HPV, whereas blockade of complex IV (sodium azide unspecifically inhibited both HPV and U46619-induced constriction. Succinate blocked HPV whereas fumarate had minor effects on vasoconstriction. Conclusion This study establishes the first model for investigation of basic characteristics of HPV

  5. Hepatic calcium efflux during cytochrome P-450-dependent drug oxidations at the endoplasmic reticulum in intact liver.

    Science.gov (United States)

    Sies, H; Graf, P; Estrela, J M

    1981-06-01

    During metabolism of (type I) drugs by cytochrome P-450-dependent monooxygenase of the endoplasmic reticulum, the NADPH/NADP+ ratio in rat liver selectively decreases to approximately one-half of the control values, whereas the NADH/NAD+ ratio remains practically unaffected [Sies, H. & Brauser, B. (1970) Eur. J. Biochem. 15, 521-540]. In view of the observations with isolated mitochondria [Lehninger, A. L., Vercesi, A. & Bababunmi, E. A. (1978) Proc. Natl. Acad. Sci. USA 75, 1690-1694] of stimulated Ca2+ efflux upon nicotinamide nucleotide oxidation, the selective oxidation of NADPH in cytosol and mitochondria during drug oxidations was considered a useful experimental tool for the determination of whether the oxidation of NADPH or of NADH is responsible for Ca2+ efflux. With perfused livers from phenobarbital-treated rats, Ca2+ efflux was demonstrated, amounting to 8 nmol/min per gram of liver (wet weight), with aminopyrine, ethylmorphine, or hexobarbital as drug substrates. Drug-associated Ca2+ release was diminished when the inhibitor metyrapone was also present, or when drug oxidation was suppressed during N2 anoxia or in the presence of antimycin A in livers from fasted rats. Ca2+ efflux was elicited also by infusion of the thiol oxidant diamide, and by t-butyl hydroperoxide. However whereas Ca2+ efflux elicited by these compounds was restricted upon addition of the thiol dithioerythritol, there was little, if any, sensitivity of the drug-associated Ca2+ efflux to the thiol. Further mitochondrial oxidation of NADPH by addition of ammonium chloride had no effect on drug-associated Ca2+ efflux. Prior addition of the alpha-agonist phenylephrine suppressed the Ca2+ release by drug addition. While the molecular mechanism involved in Ca2+ efflux from liver mitochondria and from hepatocytes as well as the regulatory significance are not yet known, it is concluded from the present experiments that in case of nicotinamide nucleotide-linked Ca2+ efflux the oxidation of

  6. Kalispel Non-Native Fish Suppression Project 2007 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wingert, Michele; Andersen, Todd [Kalispel Natural Resource Department

    2008-11-18

    Non-native salmonids are impacting native salmonid populations throughout the Pend Oreille Subbasin. Competition, hybridization, and predation by non-native fish have been identified as primary factors in the decline of some native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarki lewisi) populations. In 2007, the Kalispel Natural Resource Department (KNRD) initiated the Kalispel Nonnative Fish Suppression Project. The goal of this project is to implement actions to suppress or eradicate non-native fish in areas where native populations are declining or have been extirpated. These projects have previously been identified as critical to recovering native bull trout and westslope cutthroat trout (WCT). Lower Graham Creek was invaded by non-native rainbow (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis) after a small dam failed in 1991. By 2003, no genetically pure WCT remained in the lower 700 m of Graham Creek. Further invasion upstream is currently precluded by a relatively short section of steep, cascade-pool stepped channel section that will likely be breached in the near future. In 2008, a fish management structure (barrier) was constructed at the mouth of Graham Creek to preclude further invasion of non-native fish into Graham Creek. The construction of the barrier was preceded by intensive electrofishing in the lower 700 m to remove and relocate all captured fish. Westslope cutthroat trout have recently been extirpated in Cee Cee Ah Creek due to displacement by brook trout. We propose treating Cee Cee Ah Creek with a piscicide to eradicate brook trout. Once eradication is complete, cutthroat trout will be translocated from nearby watersheds. In 2004, the Washington Department of Fish and Wildlife (WDFW) proposed an antimycin treatment within the subbasin; the project encountered significant public opposition and was eventually abandoned. However, over the course of planning this 2004 project, little public

  7. High Intensity Interval Training (HIIT) Induces Specific Changes in Respiration and Electron Leakage in the Mitochondria of Different Rat Skeletal Muscles

    Science.gov (United States)

    de-Souza-Ferreira, Eduardo; Guerra Martinez, Camila; Kurtenbach, Eleonora; Casimiro-Lopes, Gustavo; Galina, Antonio

    2015-01-01

    High intensity interval training (HIIT) is characterized by vigorous exercise with short rest intervals. Hydrogen peroxide (H2O2) plays a key role in muscle adaptation. This study aimed to evaluate whether HIIT promotes similar H2O2 formation via O2 consumption (electron leakage) in three skeletal muscles with different twitch characteristics. Rats were assigned to two groups: sedentary (n=10) and HIIT (n=10, swimming training). We collected the tibialis anterior (TA-fast), gastrocnemius (GAST-fast/slow) and soleus (SOL-slow) muscles. The fibers were analyzed for mitochondrial respiration, H2O2 production and citrate synthase (CS) activity. A multi-substrate (glycerol phosphate (G3P), pyruvate, malate, glutamate and succinate) approach was used to analyze the mitochondria in permeabilized fibers. Compared to the control group, oxygen flow coupled to ATP synthesis, complex I and complex II was higher in the TA of the HIIT group by 1.5-, 3.0- and 2.7-fold, respectively. In contrast, oxygen consumed by mitochondrial glycerol phosphate dehydrogenase (mGPdH) was 30% lower. Surprisingly, the oxygen flow coupled to ATP synthesis was 42% lower after HIIT in the SOL. Moreover, oxygen flow coupled to ATP synthesis and complex II was higher by 1.4- and 2.7-fold in the GAST of the HIIT group. After HIIT, CS activity increased 1.3-fold in the TA, and H2O2 production was 1.3-fold higher in the TA at sites containing mGPdH. No significant differences in H2O2 production were detected in the SOL. Surprisingly, HIIT increased H2O2 production in the GAST via complex II, phosphorylation, oligomycin and antimycin by 1.6-, 1.8-, 2.2-, and 2.2-fold, respectively. Electron leakage was 3.3-fold higher in the TA with G3P and 1.8-fold higher in the GAST with multiple substrates. Unexpectedly, the HIIT protocol induced different respiration and electron leakage responses in different types of muscle. PMID:26121248

  8. Changes of energy metabolic pathway of hypertrophic cardiomyocytes and effect of intervening with drugs%肥大心肌细胞能量代谢途径变化及药物干预效应研究

    Institute of Scientific and Technical Information of China (English)

    冯兵; 徐静; 刘伟; 杨旭; 何作云; 杨惠标

    2006-01-01

    目的探讨肥大心肌细胞能量代谢途径变化及药物干预的作用.方法应用血管紧张素Ⅱ (angiotensin Ⅱ, Ang Ⅱ, 0.1μmol/L)加去甲肾上腺素(norepinephrine, NE 1μmol/L)诱导培养大鼠心肌细胞肥大,以同位素液闪计数法测定丙酮酸脱氢酶(pyruvate dehydrogenase,PDH)、肉碱脂酰转移酶-1(carnitine palmitoyltransferase 1, CPT-1)活性,以及葡萄糖有氧氧化率、葡萄糖酵解率和脂肪酸有氧氧化率.结果 (1)与正常心肌细胞比较,肥大心肌细胞总的PDH活性没有明显改变,但活化型PDH活性和葡萄糖氧化代谢率(glucose oxidation rate, GOR)显著增强,CPT-1活性和脂肪酸有氧氧化代谢率(fatty acid oxidation rate, FOR)显著降低;(2)与对照肥大心肌细胞比较,二氯乙酸(dichloroacetate,DCA 1000~10000mmol/L)和曲美他嗪(Trimetazidine,TMZ 1~5mmol/L)呈剂量依赖性的升高PDH活性和GOR,抑制CPT-1活性、FOR和葡萄糖酵解率(glucolysis rate, GLR);(3)与对照肥大心肌细胞比较,抗霉素A(antimycin A,0.1~10mmol/L)呈剂量依赖性的抑制PDH活性和GOR和GLR,增强CPT-1活性和FOR;(4)二氯乙酸(1000mmol/L)加曲美他嗪(1mmol/L)可更有效刺激PDH活性和GOR,抑制CPT-1活性、FOR和GLR.结论肥大心肌细胞能量代谢向糖代谢转化,DCA和TMZ均可进一步增强糖有氧氧化代谢抑制脂肪酸代谢.

  9. High Intensity Interval Training (HIIT Induces Specific Changes in Respiration and Electron Leakage in the Mitochondria of Different Rat Skeletal Muscles.

    Directory of Open Access Journals (Sweden)

    Dionizio Ramos-Filho

    Full Text Available High intensity interval training (HIIT is characterized by vigorous exercise with short rest intervals. Hydrogen peroxide (H2O2 plays a key role in muscle adaptation. This study aimed to evaluate whether HIIT promotes similar H2O2 formation via O2 consumption (electron leakage in three skeletal muscles with different twitch characteristics. Rats were assigned to two groups: sedentary (n=10 and HIIT (n=10, swimming training. We collected the tibialis anterior (TA-fast, gastrocnemius (GAST-fast/slow and soleus (SOL-slow muscles. The fibers were analyzed for mitochondrial respiration, H2O2 production and citrate synthase (CS activity. A multi-substrate (glycerol phosphate (G3P, pyruvate, malate, glutamate and succinate approach was used to analyze the mitochondria in permeabilized fibers. Compared to the control group, oxygen flow coupled to ATP synthesis, complex I and complex II was higher in the TA of the HIIT group by 1.5-, 3.0- and 2.7-fold, respectively. In contrast, oxygen consumed by mitochondrial glycerol phosphate dehydrogenase (mGPdH was 30% lower. Surprisingly, the oxygen flow coupled to ATP synthesis was 42% lower after HIIT in the SOL. Moreover, oxygen flow coupled to ATP synthesis and complex II was higher by 1.4- and 2.7-fold in the GAST of the HIIT group. After HIIT, CS activity increased 1.3-fold in the TA, and H2O2 production was 1.3-fold higher in the TA at sites containing mGPdH. No significant differences in H2O2 production were detected in the SOL. Surprisingly, HIIT increased H2O2 production in the GAST via complex II, phosphorylation, oligomycin and antimycin by 1.6-, 1.8-, 2.2-, and 2.2-fold, respectively. Electron leakage was 3.3-fold higher in the TA with G3P and 1.8-fold higher in the GAST with multiple substrates. Unexpectedly, the HIIT protocol induced different respiration and electron leakage responses in different types of muscle.

  10. Non-endothelial endothelin counteracts hypoxic vasodilation in porcine large coronary arteries

    Directory of Open Access Journals (Sweden)

    Fröbert Ole

    2011-05-01

    glycol catalase (300 u/ml inhibited H2O2 vasodilation, but failed to affect vasodilation to O2 lowering. Neither did PEG-SOD (polyethylene glycol superoxide dismutase(70 u/ml affect vasodilation to O2 lowering. The mitochondrial inhibitors rotenone (1 μM and antimycin A (1 μM both inhibited hypoxic vasodilatation. Conclusion The present results in porcine coronary arteries suggest NO contributes to hypoxic vasodilation, probably through K channel opening, which is reversed by addition of ET-1 and enhanced by endothelin receptor antagonism. These latter findings suggest that endothelin receptor activation counteracts hypoxic vasodilation.

  11. 电子传递链对白念珠菌菌丝形成的影响%Effect of electron transfer system on the hyphal formation of Candida albicans

    Institute of Scientific and Technical Information of China (English)

    刘泽虎; 吕雪莲; 李筱芳; 吕桂霞; 沈永年; 李岷; 刘维达

    2009-01-01

    to assess the viability of Candida albicans. Results The solvents (chloroform and dimethyl sulfoxide) had no significant effect on the growth of and filamentation in Candida albicans. After incubation with thenoyltrifluoroacetone (TTFA) or benzhydroxamic acid for 24 hours, yeast cells of Candida albicans predominated in the culture. The growth of Candida albicans was significantly inhibited in log phase by the incubation with classic respiratory chain inhibitors such as rotenone, antimycin A, oligomycin, sodium azide, TTFA and sodium malonate, compared with the controls (all P < 0.01). Benzhydroxamic acid, an inhibitor of alternative oxidative pathway, also significantly inhibited the growth of Candida albicans in log phase (t = 10.92, P < 0.01). After incubation with rotenone, antimycin A, oligomycin, sodium azide, TTFA, sodium malonate, benzhydroxamic acid and disodium gnanylate, the percentage of filamentation in Candida albicans at 12 hours was 87.49 ± 0.52, 48.75 ± 4.44, 50.33 ± 8.50, 99.00 ± 1.00, 1.60 ± 0.53, 94.01 ± 0.99, 0.00 ± 0.00 and 92.33 ± 2.08, respectively, and the growth of Candida albicans at 7 hours was inhibited by (1.34 ± 0.15)%, (70.61 ± 1.02)%, (50.63 ± 5.38)%, (17.80 ± 7.89)%, (45.17 ± 1.27)%, (10.75 ± 3.62)%, (72.46 ± 1.14)% and -(5.96 ± 4.07)%, respectively. Conclusions Hyphal formation of Candida albicans could be suppressed by inhibitors of classic respiratory chain or alternative oxidative pathway, and is mainly regulated by alternative oxidative pathway.

  12. Standardization of in vitro cell-based model for renal ischemia and reperfusion injury

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    Gino A Kurian

    2014-01-01

    Full Text Available Renal ischemia reperfusion injury contributes patho-physiological imbalance of acute renal failure that comprises of generation of reactive oxygen species, nitric oxide and peroxynitrite and inflammation involving cytokine/adhesion molecule cascade, finally leads to cell death. Oxygen deprival associated with ischemia that in turn lead to decline ATP production is the characteristic feature usually addressed in the development of in vitro cell based ischemic model. In order to create oxygen deficit in the cell lines different approaches like chemical induction, enzymatic induction and anaerobic chamber models are widely used. However efficiencies of these models were varied and the present study was aimed to compare the suitability of these models in creating in vitro ischemia reperfusion in cell culture. In the chemical induced method we used different concentrations of rotenone, antimycin and sodium azide to inhibit electron transport chain and thereby reduced the ATP production, measured indirectly by cell viability assay. Among the chemical induced model, antimycin mediated cell injury was more reliable for ischemia reperfusion study. In the enzymatic model, comprises of glucose oxidase (3mM/s and catalase (998 s -1 at 10:1 ratio was used and found to be best among the three approaches as it can create injury in short experimental time and are reproducible. However anaerobic chamber method was not suitable for ischemia reperfusion study as it need more time to induce significant cell injury.

  13. JRRD a a Glance

    Directory of Open Access Journals (Sweden)

    Editor

    2012-06-01

    Full Text Available Contains a plain language discription of articles published in this issue including Robot-assisted therapy, prosthetic knee joint maneuverability, community reintegration, and more

  14. The pathway of inorganic-phosphate efflux from isolated liver mitochondria during adenosine triphosphate hydrolysis.

    Science.gov (United States)

    Tyler, D D

    1980-12-15

    1. The distribution of P(i) between mitochondria and suspending medium during uncoupler-stimulated hydrolysis of ATP by rat liver mitochondria [Tyler (1969) Biochem. J.111, 665-678] has been reinvestigated, by using either mersalyl or N-ethylmaleimide as inhibitors of P(i) transport and either buffered sucrose/EDTA or LiCl/EGTA solutions as suspending medium. More than 75% of the total P(i) liberated was retained in mitochondria treated with either inhibitor at all ATP concentrations tested (0.2-2.5mm). With low ATP concentrations and mersalyl-treated mitochondria incubated in sucrose/EDTA, virtually all the P(i) liberated was retained in the mitochondria. 2. Larger amounts of P(i) appeared in the suspending medium during ATPase activity, despite the presence of N-ethylmaleimide, when LiCl/EGTA was used as suspending medium compared with sucrose/EDTA. Two sources of this P(i) were identified: (a) a slow efflux of P(i) from mitochondria to suspending medium despite the presence of N-ethylmaleimide; (b) a slow ATPase activity insensitive to carboxyatractyloside, which was stimulated by added Mg(2+), partially inhibited by oligomycin or efrapeptin and strongly inhibited by EDTA. 3. It is concluded that liver mitochondria preparations contain two distinct forms of ATPase activity. The major activity is associated with coupled mitochondria of controlled permeability to adenine nucleotides and P(i) and is stimulated strongly by uncoupling agents. The minor activity is associated with mitochondria freely permeable to adenine nucleotides and P(i), is unaffected by uncoupling agents and is activated by endogenous or added Mg(2+). 4. When mitochondria treated with mersalyl were incubated in buffered sucrose solution, almost all the P(i) liberated was recovered in the suspending medium, unless inhibitors of P(i)-induced large-amplitude swelling such as EDTA, EGTA, antimycin, rotenone, nupercaine or Mg(2+) were added. Thus the loss of the specific permeability properties of

  15. PHOSPHORYLATION/DEPHOSPHORYLATION OF MITOCHONDRIAL PROTEINS IN REDOX-SIGNALLING OF HIGHER PLANTS UNDER ABIOTIC STRESS CONDITIONS

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    Subota I.Yu.

    2012-08-01

    Full Text Available We studied an impact of the widely spread intra-cellular signals Ca2+ and сAMP on activity of the protein phosphorylation in maize mitochondria. The use of the isolated mitochondria is a convenient model system for investigation of the different physiological processes, for example for simulation of the different stress conditions. The treatment of maize mitochondria with high concentration of calcium ions which mimics the initial stage of apoptosis led to an increase of the phosphorylation level of some proteins and to an additional phosphorylation of the 59 and 66 kDa proteins. The treatment of the mitoplasts, i.e., the mitochondria devoid of the outer membrane with calcium ions insignificantly induced the activity of protein phosphorylation. It is assumed that the outer membrane is essential for Ca2+ signal transduction to plant mitochondria. We also identified a 94 kDa protein involved in phosphorylation of the mitochondrial proteins. This protein might be a single-subunit protein kinase or one of the subunits of the protein kinase complex. Antimycin A and KCN which are the inhibitors of mitochondria respiration increased the phosphorylation activity of the mitochondrial polypeptides. The effect of this inhibitors was similar both in in organello system and at the level of the whole plant. It should be noticed that at the level of the whole plant the effect of KCN on activity of the mitochondrial protein phosphorylation was more essential. Some considerable differences were found both at the level of protein phosphorylation and in electrophoresis patterns representing the intact mitochondria, the mitoplasts and the outer membrane fraction. The activity of protein phosphorylation in mitoplasts and the outer membrane fraction was extremely high compared to the phosphorylation activity of the mitochondrial proteins. This could be explained by the higher level of “substrate phosphoprotein phosphatase” in the outer membrane of mitochondria

  16. Apparent Km of mitochondria for oxygen computed from Vmax measured in permeabilized muscle fibers is lower in water enriched in oxygen by electrolysis than injection

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    Zoll J

    2015-07-01

    Full Text Available Joffrey Zoll,1 Jamal Bouitbir,1 Pascal Sirvent,2 Alexis Klein,3 Antoine Charton,1,4 Liliana Jimenez,3 François R Péronnet,5 Bernard Geny,1 Ruddy Richard61Physiology Department, Faculty of Medicine and EA3072, Université de Strasbourg, Strasbourg, 2Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l’Exercice en Conditions Physiologiques et Pathologiques, Clermont-Ferrand, 3Danone Research, Centre Daniel Carasso, Palaiseau, 4Department of Anesthesia and Critical Care and EA3072, Hôpital de Hautepierre, Université de Strasbourg, France; 5Kinesiology Department, Université de Montréal, Montréal, QC, Canada; 6Department of Sport Medicine and Functional Explorations and INRA UMR 1019, Faculty of Medicine, Université d’Auvergne, Clermont-Ferrand, FranceBackground: It has been suggested that oxygen (O2 diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates, which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients.Materials and methods: Mitochondrial respiration was compared in situ in saponin-skinned fibers isolated from the soleus muscles of Wistar rats, in solution enriched in O2 by injection or the electrolytic process 1 at an O2 concentration decreasing from 240 µmol/L to 10 µmol/L (132 mmHg to 5 mmHg, with glutamate–malate or N, N, N', N'-tetramethyl-p-phenylenediamine dihydrochloride (TMPD–ascorbate (with antimycin A as substrates; and 2 at increasing adenosine diphosphate (ADP concentration with glutamate–malate as substrate.Results: As expected, maximal respiration decreased with O2 concentration and, when compared to glutamate–malate, the apparent Km O2 of mitochondria for O2 was significantly lower with TMPD–ascorbate with both waters. However, when compared to the water enriched in O2 by injection, the Km O2 was

  17. Bisphenol A

    Science.gov (United States)

    ... in Environmental Health, Chemistry, and Toxicology More Resources Bisphenol A (BPA) en español Bisphenol A (BPA) is used to make lightweight, hard plastics. What is bisphenol A? Bisphenol A, also called BPA, is a ...

  18. Vitamin A

    Science.gov (United States)

    Vitamins are substances that your body needs to grow and develop normally. Vitamin A plays a role in your Vision Bone growth Reproduction Cell functions Immune system Vitamin A is an antioxidant. It can come from ...

  19. Hepatitis A

    Science.gov (United States)

    ... an inflammation of the liver. One type, hepatitis A, is caused by the hepatitis A virus (HAV). The disease spreads through contact with ... washed in untreated water Putting into your mouth a finger or object that came into contact with ...

  20. From a = b to a = a

    OpenAIRE

    Gunnar Olsson

    2000-01-01

    In this paper I compare and contrast the alternative treatments of the Other as they appear first in the radical geography of 1968, then in the political geography of 1998. While in the Hegelian sixties both the master and the slave recognized that they are defined in terms of each other (a = b), the politically correct of the nineties are claiming that the right to define who you are is yours and yours alone (a = a). But whoever argues that the only acceptable truth lies in the statement "I ...

  1. A literatura e a teologia

    Directory of Open Access Journals (Sweden)

    Genilma Boehler

    2011-04-01

    Full Text Available Trata-se de uma reflexão sobre literatura e teologia, pontualmente sobre poesia e teologia. Como afirmou Edgar Morin “a literatura tem a vantagem de refletir sobre a complexidade do ser humano e sobre a quantidade incrível de seus sonhos” (MORIN, 2009:6. Já a teologia, como definida por Rubem Alves, é “um jeito de falar sobre tais coisas dando-lhes um nome e apenas distinguindo-se da poesia porque a teologia é sempre feita como prece...” (ALVES, 2005:21. O encontro das duas é a ocasião para que seja feita uma reflexão acerca de Deus, a partir do espaço da poesia, recorrendo a outra linguagem, outro conhecimento, outras bibliotecas, considerando o corpo, o desejo, a vida, o mundo na medida em que apresenta a pessoa, a sociedade e a cultura.

  2. Cygnus A

    NARCIS (Netherlands)

    Carilli, CL; Barthel, PD

    1996-01-01

    Cygnus A was the first hyper-active galaxy discovered, and it remains by far the closest of the ultra-luminous radio galaxies. As such, Cygnus A has played a fundamental role in the study of virtually all aspects of extreme activity in galaxies. We present a review of jet theory for powering the dou

  3. A gravimeter

    Energy Technology Data Exchange (ETDEWEB)

    Aliyev, T.M.; Asadov, A.M.; Dzhagupov, R.G.; Gadzhiyev, A.A.; Yakubov, R.A.

    1979-04-30

    A gravimeter is patented consisting of a sensitive element in the form of a lever connected with the recording instrument's spring, and a heat compensation unit. To raise the measurement accuracy, the heat compensation unit is made in the form of a piezoelectric plate firmly connected with the spring and joined with the measurement resistor direct current bridge, to one of whose arms is switched in the temperature-sensitive resistor.

  4. A Writer, a Translator and a Translator

    Directory of Open Access Journals (Sweden)

    Katarina Marinčič

    2015-12-01

    Full Text Available The article deals with the French translation of the short story Amy by the Slovenian writer Mira Mihelič, made by Elza Jereb for the anthology Nouvelles slovènes (Paris, 1969. The original text, a classical narrative involving some modernist strategies, presents a syntactical feature rather unusual in Slovenian (although typical of the author Mira Mihelič: a very frequent use of participles and participial structures. Elza Jereb’s translation is accurate and precise, preserving not only the basic meaning but also the stylistic qualities, particularly the internal rhythm of the original. Some slight changes (such as for example a more consequent and logical use of italics render the text accessible to the French reader without undue simplifications. The only part of the original that seems to get lost in translation are some minor parts of the dialogue: the phonetically transcribed provincial German of the original, rich in social connotations, is translated into standard literary German, thereby losing some of its sociohistorical implications as well as some of its comical potential. 

  5. Vitamin A

    Science.gov (United States)

    ... carotenoid is beta-carotene. Beta-carotene is an antioxidant. Antioxidants protect cells from damage caused by substances called ... A can lead to hyperkeratosis or dry, scaly skin. If you get too much vitamin A, you ...

  6. A118

    Directory of Open Access Journals (Sweden)

    A. Kozlov

    2015-11-01

    It can be concluded that expression of protogenes, evolutionarily young and/or novel genes in tumors might be a new biological phenomenon, a phenomenon of carcino-evo-devo genes, predicted by the hypothesis of evolution by tumor neofunctionalization.

  7. Hemophilia A

    Science.gov (United States)

    Factor VIII deficiency; Classic hemophilia; Bleeding disorder - hemophilia A ... When you bleed, a series of reactions take place in the body that helps blood clots form. This process is called the coagulation ...

  8. A Ciberguerra

    OpenAIRE

    Melo, Pedro

    2011-01-01

    O Trabalho estuda a Ciberguerra e o modo como as Forças Armadas se podem estruturar para melhor enfrentar as ameaças que a enformam. A massificação da Internet mudou o mundo e é consensual que nada alguma vez o mudou tão rapidamente, quanto a Internet o tem feito, trazendo desafios novos, para os quais ainda se procuram as respostas e faz com que a guerra no Ciberespaço seja considerada uma preocupação prioritária e se encontre no topo da agenda dos decisores políticos mundiais e das organiza...

  9. A container

    DEFF Research Database (Denmark)

    2012-01-01

    A container assembly for the containment of fluids or solids under a pressure different from the ambient pressure comprising a container (2) comprising an opening and an annular sealing, a lid (3) comprising a central portion (5) and engagement means (7) for engaging the annular flange, and sealing...... means (10) wherein the engagement means (7) is adapted, via the sealing means, to seal the opening when the pressure of the container assembly differs from the ambient pressure in such a way that the central portion (5) flexes in the axial direction which leads to a radial tightening of the engagement...... means (7) to the container, wherein the container further comprises locking means (12) that can be positioned so that the central portion is hindered from flexing in at least one direction....

  10. A Keyboard

    DEFF Research Database (Denmark)

    2008-01-01

    The present invention relates to a keyboard with a plurality of keys with key switches that are covered by a flexible display for displaying individual labels of the keys whereby the label can be changed during operation of the keyboard by appropriate control of the keyboard. The flexible display...... is pre-shaped into a non-planar shape to fit on top of the key switches so that each key switch can be activated by depressing the area of the flexible display displaying the key label of the key switch in question. Each key may have a key cap with a transparent top surface with the flexible display...... mounted underneath the key cap for displaying the individual label of the key viewable through the transparent top surface of the key cap. The keyboard provides tactile feedback similar to a conventional high quality keyboard....

  11. A Visit With a Curandero

    OpenAIRE

    Mull, J. Dennis; Mull, Dorothy S

    1983-01-01

    One author visited a Mexican-American folk healer in the Los Angeles area, not as a patient but as a fellow health professional. Information was obtained from this healer, a curandero, regarding his background, his clientele, the illnesses he treats, the therapeutic techniques he uses and his relationship with the official health care system. This information was generally consistent with statements about curanderismo that have appeared in the social sciences literature. It also provided addi...

  12. A terra, a tela e a letra

    Directory of Open Access Journals (Sweden)

    Susanna Busato Feitosa

    2006-12-01

    Full Text Available Este estudo visa elaborar uma leitura dos aspectos semióticos que organizam os espaços de significação no processo da formação cultural brasileira a partir dos processos tradutórios realizados por parte das expedições exploratórias que para os trópicos vieram. Investigam-se, assim, por meio de relações em nível paradigmático e sintagmático, as produções pictóricas dos artistas viajantes dos séculos XVII, Albert Eckhout e Frans Post, e as produções poéticas barrocas de Gregório de Matos, Manuel Botelho de Oliveira e Manuel de Santa Maria Itaparica.

  13. A Proposal

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    正All the students in our school, A sudden 8.0 earthquake happened in Wenchuan, Sichuan Province at 2:28 on the afternoon of May 12, 2008. Many houses fell down and lots of people have become homeless. A large number of people were badly injured and so many people lost their lives. The people in

  14. A Dog

    Institute of Scientific and Technical Information of China (English)

    韩选文

    2004-01-01

    A dog can't speak words, but it can "talk", It has feelings just as you do. At times it may feel angry or afraid. Watching a dog closely, you can find out what it feels. You can see what it is trying to tell you.

  15. A atmosfera

    OpenAIRE

    Gómez Fórneas, Esther; Rodríguez Silva, Laura

    2009-01-01

    Despois de estudar os conceptos básicos da química, as propiedades dos gases, os líquidos, os sólidos, as disolucións, os enlaces químicos, as forzas intermoleculares e visto como a cinética química e os conceptos de equilibrio axudan a entender a natureza das reaccións químicas, neste tema imos aplicar estes coñecementos ao estudo do sistema atmosfera. No entanto que a composición da atmosfera da terra é bastante simple, a súa química é moi complexa e nunca se comprendeu por completo. Os pro...

  16. A luta contra a Pirataria

    OpenAIRE

    Ramos, Nuno

    2010-01-01

    A Pirataria Marítima não é um fenómeno novo. Historicamente, a sua preponderância e importância era considerável porque a insegurança dos mares foi, durante séculos, um factor dominante. A realidade da existência da Pirataria Marítima, apesar de nunca ter desaparecido do mapa mundial, sofreu uma redução muito significativa ao longo dos anos, tendo recrudescido nos últimos tempos. A Pirataria Marítima é de âmbito global, existindo contudo diferenciação regional. Anualmente são reportadas...

  17. A Rejoinder

    Directory of Open Access Journals (Sweden)

    Nelson Lichtenstein

    2006-03-01

    Full Text Available It is a pleasure and a challenge to engage these commentaries on my recent book, State of the Union: a Century of American Labor. The pleasure is there because this author, like almost every other, is deeply appreciative of the kind of critical attention, and sheer energy, to which his work is subject. The commentators assembled by Jean‑Christain Vinel understood with remarkable precision the main line of argument I was trying to advance, which has not always been the case on the American sid...

  18. Hall A

    Data.gov (United States)

    Federal Laboratory Consortium — The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electroand photo-induced reactions at very high luminosity...

  19. A Symposium.

    Science.gov (United States)

    Rachal, John R.

    2003-01-01

    Uses the framework of a symposium to present an imagined discussion by historical figures about whether and how knowledge might be acquired. Discussants include Democritus, Protagoras, Heraclitus, Socrates, Jesus, Gorgias, Nietzsche, Buddha, and Kierkegaard. (Contains 40 endnotes.) (SK)

  20. Q & A

    Directory of Open Access Journals (Sweden)

    Prof.. Adam Micolich

    2012-07-01

    Full Text Available Prof. Adam Micolich is a researcher based at the University of New South Wales, specializing in the study of semiconductor systems. Materials Today recently spoke to Adam for our podcast.

  1. A JOKE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Grandpa and granddaughter were sitting talking when she asked,“Did God make you,Grandpa?”“Yes,God made me,”the grandfather answered.A few minutes later,the little girl asked him,“Did God make me too?”“Yes,He did,”the older man answered.For a few minutes,the little girl seemed to be studying

  2. A110

    Directory of Open Access Journals (Sweden)

    T. Malivanova

    2015-11-01

    Conclusions: This study found out the opposite effect of polymorphisms at −238 and −308 positions in TNF promoter on the outcome of BC patients. Carriers of low expressed allele −238(A have poor outcome because of low response to standard hormone therapy which presumably connected with the activation of Her2 pathway. The obtained results allow supposing that a special approach to the treatment of this group of BC patients should be used.

  3. A School without a Principal.

    Science.gov (United States)

    Barnett, Demian; McKowen, Charlene; Bloom, Gary

    1998-01-01

    Teachers at a central California high school operate the school according to a strict, progressive set of principles. The Anzar communication guidelines specify teachers' commitment to communicating well, collective ownership of problems and problem solving, tolerance of differing ideas, individual accountability, dedication to helping and…

  4. A Blizzard of a Value

    Science.gov (United States)

    Bostic, Jonathan D.

    2015-01-01

    "Who has been to Dairy Queen® and purchased a Blizzard?®" Ms. Bosetti asked her students. During the summer, Bosetti had seen many of her former and future students at the local Dairy Queen enjoying Blizzard desserts and wondered, "Which Blizzard size is the best value?" She used this context for a ratios and proportions task…

  5. A Giant or a Dwarf?

    DEFF Research Database (Denmark)

    Schmid, Herman

    2005-01-01

    EU may appear to be a giant when it can act on behalf of a united Europe, but usually it is hampered by conflicting member state interests. The EU economic and administrative resources for foreign and trade policy are quite small (on level with one of its major member states) and the hopes in many...

  6. Thailandepsin A

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    2011-11-01

    Full Text Available Thailandepsin A [systematic name: (E-(1S,5S,6R,9S,20R-6-[(2S-butan-2-yl]-5-hydroxy-20-[2-(methylsulfanylethyl]-2-oxa-11,12-dithia-7,19,22-triazabicyclo[7.7.6]docosa-15-ene-3,8,18,21-tetraone], C23H37N3O6S3, is a newly reported [Wang et al. (2011. J. Nat. Prod. doi:10.1021/np200324x] bicyclic depsipeptide that has potent histone deacetylase inhibitory activity and broad-spectrum antiproliferative activity. The absolute configuration of thailandepsin A has been determined from the anomalous dispersion and the stereochemistry of all chiral C atoms. Intramolecular N—H...O and N—H...S hydrogen bonds occur. Intermolecular N—H...O and O—H...O hydrogen bonds are observed in the crystal structure.

  7. A Model

    Institute of Scientific and Technical Information of China (English)

    Liu Zhiyang

    2011-01-01

    Similar to ISO Technical Committees,SAC Technical Committees undertake the management and coordination of standard's development and amendments in various sectors in industry,playing the role as a bridge among enterprises,research institutions and the governmental standardization administration.How to fully play the essential role is the vital issue SAC has been committing to resolve.Among hundreds of SAC TCs,one stands out in knitting together those isolated,scattered,but highly competitive enterprises in the same industry with the "Standards" thread,and achieving remarkable results in promoting industry development with standardization.It sets a role model for other TCs.

  8. A vet with a vision.

    Science.gov (United States)

    Ben-Shlomo, Gil

    2016-09-10

    When he learned what being a veterinarian meant, Gil Ben-Shlomo felt that the career had been invented especially for him. He has since specialised, and is now professor of ophthalmology at Iowa State University. PMID:27609975

  9. A&A Planning System

    Data.gov (United States)

    US Agency for International Development — This is a set of approximately 140 spreadsheets used by OAA. Each operating unit within USAID has its own spreadsheet that tracks all planned actions over $ 150,000...

  10. A quackery with a difference

    DEFF Research Database (Denmark)

    Wahlberg, Ayo

    2007-01-01

    The figure of the ‘miracle cure’-peddling quack pretending spectacular properties for worthless tonics is iconic. From their 19th century traveling wagon shows to their 21st century Internet spam scams, hucksters and cranks have been consistently targeted by health authorities as a danger to public...... health. Yet, in this paper, I argue that this is only one form that the problem of ‘quackery’ has taken in the past two centuries or so in the United Kingdom. Just as Roy Porter showed how the mid-19th century professionalization of medicine gave rise to a ‘quackery with a difference’ as a whole range of...... new medical movements—homoeopathy, hydropathy, medical botany, mesmerism—actively denounced allopathic or modern medicine, I will suggest that the late 20th century birth of ‘complementary and alternative medicine’ (CAM) has resulted in yet another transformation in quackery. By examining the ways in...

  11. A75

    Directory of Open Access Journals (Sweden)

    D. Korobkov

    2015-11-01

    It may be concluded that the cellular and molecular mechanisms of breast cancer are complex. Therefore, carcinogenesis has a “multistep” nature and at least two or more mutations in the cells of the same clone – parent and child are required to generate malignant tumors. Thus, the development of oncogenic transformation does not necessarily mean the process of tumor formation.

  12. Appendix A

    DEFF Research Database (Denmark)

    Henriksen, M. S.; Brincker, Rune; Heshe, Gert

    In this appendix a brief summary of experiments on reinforced concrete beams in three-point bending performed at Aalborg University is given. The aim of the investigation is to determine the full load-deflection curves for different beam sizes, different types of concrete and different amounts and...

  13. A Tribute

    Science.gov (United States)

    Bhattacharya, Dipankar

    2000-03-01

    Renowned astrophysicist Prof. Bhaskar Datta passed away in Bangalore on December 3rd, 1999 after a brave battle with cancer. He was 50. In his career spanning more than 25 years he worked extensively in the area of High-energy astrophysics, Astro-particle physics, General relativity and Cosmology. In particular, he specialized in the structure and properties of neutron stars. Prof. Datta was born and educated in Delhi. After obtaining his Master's degree in Physics from the Delhi University he worked in NORDITA, Copenhagen as a Guest Physicist. The following year he moved to the NASA Goddard Institute of Space Studies, New York, where he worked with Prof. V. Canuto for his Ph.D. thesis. He obtained his Ph.D. from City University of New York in 1977 for his work on spin-2 interaction in a relativistic neutron gas. He derived an equation of state of matter at high density using this interaction and demonstrated its effect on the derived masses and moments of inertia of neutron stars. Many years later he and his colleagues were to derive yet another Equation of State for neutron star matter, based on the chiral sigma model that includes a dynamically generated isoscalar vector field. Prof. Datta returned to India in 1978 after brief stays at University of Florida and International Centre for Theoretical Physics, Trieste, Italy. From 1978 to 1982 he worked at the Tata Institute of Fundamental Research, Mumbai. In 1982 he moved to the Indian Institute of Astrophysics, Bangalore where he worked until his death. He also held the position of an adjunct professorship at the Raman Research Institute, Bangalore. Prof. Datta's move to Bangalore coincided with the discovery of the fastest spinning neutron star known, namely the millisecond pulsar PSR 1937+21. By then already a recognised expert on neutron star structure, he plunged headlong into computing the structure with fast rotation. He, with his colleague Alak Ray, showed that the millisecond pulsar could be spinning

  14. A128

    Directory of Open Access Journals (Sweden)

    I. Pronina

    2015-11-01

    Full Text Available RCC is one of the main problems in oncourology. MiRNA expression profiles are highly specific for malignant tumors of different locations, and can be used to detect pathological molecular biomarkers and to develop the optimal treatment for each patient. Selection of miRNAs associated with the formation and development of malignant tumors in the kidney was performed using computer databases miRWalk (http://www.ma.uni-hei-delberg.de/apps/zmf/mirwalk/ and miRBase (http://www.mir-base.org/. Paired samples of tumor and histologically normal tissue from 46 patients with RCC were studied. RNA was isolated by phenol–chloroform extraction and treated with RNase-free DNase after isolation. MiRNA expression analysis was performed by RT-qPCR using Applied Biosystems (USA kits: TaqMan® MicroRNA Assays, TaqMan® MicroRNA Reverse Transcription Kit, TaqMan® Fast Universal PCR Master Mix (2x. RNU6B was used as reference miRNA. Quantity alterations of 20 microRNAs (hsa-miR-219, -203, -148a, -129, -9, -34a, -34b, -34c-3p, -127, -193a-5p, -191, -17, -24 -2*, -339 -3p, -212, -375, -125b, -124a, -132, -137 were determined in samples of tumor compared to normal tissue biopsy from the kidney of each patient. It was shown that the expression of studied miRNAs usually decreased in RCC tumors. The largest decrease of expression was observed for miR-129, which expression was10–350-fold reduced in 93% of the samples (P < 0.05 with no change of expression in the remaining 7% of cases. MiR-375 (80% of cases,10–270-fold decrease, miR-34b (79% of cases, 10–60-fold decrease, miR-124a (70% of cases, 10–200-fold decrease also frequently showed reduced expression in tumors. In addition to the aforementioned ones, it had been shown that expression in the tumor compared with histologically normal tissue from the same patient was significantly decreased in more than half of the cases for miR-125b, miR-127, miR-203, miR-34c-3p, miR-9. Despite the fact that in 50% of cases

  15. A Pulsar and a Disk

    Science.gov (United States)

    Kohler, Susanna

    2016-07-01

    Recent, unusual X-ray observations from our galactic neighbor, the Small Magellanic Cloud, have led to an interesting model for SXP 214, a pulsar in a binary star system.Artists illustration of the magnetic field lines of a pulsar, a highly magnetized, rotating neutron star. [NASA]An Intriguing BinaryAn X-ray pulsar is a magnetized, rotating neutron star in a binary system with a stellar companion. Material is fed from the companion onto the neutron star, channeled by the objects magnetic fields onto a hotspot thats millions of degrees. This hotspot rotating past our line of sight is what produces the pulsations that we observe from X-ray pulsars.Located in the Small Magellanic Cloud, SXP 214 is a transient X-ray pulsar in a binary with a Be-type star. This star is spinning so quickly that material is thrown off of it to form a circumstellar disk.Recently, a team of authors led by JaeSub Hong (Harvard-Smithsonian Center for Astrophysics) have presented new Chandra X-ray observations of SXP 214, tracking it for 50 ks (~14 hours) in January 2013. These observations reveal some very unexpected behavior for this pulsar.X-ray PuzzleThe energy distribution of the X-ray emission from SXP 214 over time. Dark shades or blue colors indicate high counts, and light shades or yellow colors indicate low counts. Lower-energy X-ray emission appeared only later, after about 20 ks. [Hong et al. 2016]Three interesting pieces of information came from the Chandra observations:SXP 214s rotation period was measured to be 211.5 s an increase in the spin rate since the discovery measurement of a 214-second period. Pulsars usually spin down as they lose angular momentum over time so what caused this one to spin up?Its overall X-ray luminosity steadily increased over the 50 ks of observations.Its spectrum became gradually softer (lower energy) over time; in the first 20 ks, the spectrum only consisted of hard X-ray photons above 3 keV, but after 20 ks, softer X-ray photons below 2 ke

  16. A mascarada e a feminilidade

    Directory of Open Access Journals (Sweden)

    Grant Walkiria Helena

    1998-01-01

    Full Text Available Marcada por produções freudianas, a literatura analítica e, mais especificamente, aquela influenciada pelo ensino lacaniano, não pára de mostrar que as considerações anatômicas não são índices para falar da diferença de identidade sexual entre homens e mulheres. Diante do fato de que características masculinas continuavam presentes em mulheres adultas normais, Freud responde que ser mulher é ser mãe. A vacilação da verdade desta equação pode ser observada nas situações mais diversas nas quais podemos nos defrontar com mulheres, mães, desempenhando papéis de homens. Como pensar esta constatação? Este trabalho permitir-nos-á mostrar a imbricação do feminino e do masculino num caso de uma mulher com todas as características de uma feminilidade considerada normal, e também discutir a questão do gozo fálico e do Outro gozo - propostos por Lacan como índices de diferenciação da posição masculina e da feminina.

  17. A42

    OpenAIRE

    V. Yuzhakov; L. Sevankaeva; M. Konoplyannikov; N. Fomina; I. Ingel; Konoplyannikov, A.

    2015-01-01

    The mechanisms of mesenchymal stem cells (MSC) action on malignant neoplasms attract much attention nowadays. Studies relating to the MSC effect on tumors are contradictory and indicate that MSC has both stimulating and suppressive actions on experimental neoplasms. We have shown previously that a single MSC administration to tumor-bearing animals has an oncomodulating effect on the growth of tumors. Short-term stimulation of the growth of tumor nodes initially after the MSC injection was usu...

  18. A51

    OpenAIRE

    E. Zlatnik; G. Zakora; A. Bakhtin; O. Shulgina et al.

    2015-01-01

    Nanotechnologies are significant modern trend embracing various fields of science including biology and medicine. Investigations of biological activities of nanoparticles (NP) suggest perspectives of their application in oncology. The role of metals in metabolic processes in the organism is well known, but a few data are available about the activities of nanometals. Our aim was to study the effect of metallic nanoparticles on growth of xenografts of human lung cancer and transplanted mouse...

  19. A99

    OpenAIRE

    M. Suvorova; A. Tsapieva; Suvorov, A.; Kiseleva, E

    2015-01-01

    Ability of Streptococcus pyogenes to fight cancer was discovered and clinically tested more than 100 years ago (Coley, 1897), but the mechanisms of these effects are unknown. Recently several murine models demonstrating the anti-cancer activity of Group A Streptococcus (GAS) M49 were established (Maletzki, 2008). The present study is devoted to investigation of anti-cancer activity of GAS M39 strains. Tumor cells were injected subcutaneously in concentration of 200,000 cells per animal. Tw...

  20. A comme... (A as in...).

    Science.gov (United States)

    Helouber, J. A.; And Others

    1979-01-01

    The four parts in this section present: (1) an advertisement based on the literary style of Emile Zola; (2) exercises designed to practice expressions of similarity and difference; (3) the transcript of a discussion on the problem of swamps; and (4) variations on the shopkeeper-customer dialogue. (AM)

  1. A Leader, Not a Hero

    Science.gov (United States)

    Rutledge, Lynda

    2005-01-01

    The author writes her experience in leading. She points out that a good leader should know when and how to let go than trying to do all the work by herself. It changed her focus on looking at details, implementation, dealing with the contractors, to leading leading people.

  2. A Question about a Triangle

    Science.gov (United States)

    Vinogradova, Natalya

    2016-01-01

    In fall 2013 the author taught a graduate course entitled Topics in Geometry for Middle and High School Teachers. The majority of the participants had extensive experience teaching mathematics in middle school or high school. The fact that participants were rather comfortable with the basic concepts of school geometry made it both possible and…

  3. A Whale of a Panorama

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for A Whale of a Panorama (QTVR) More than 1.5 years into their exploration of Mars, both of NASA's Mars Exploration Rovers continue to send a cornucopia of images to Earth. The results are so spectacular that Deputy Project Manager John Callas recently described them as 'an embarrassment of riches.' Spirit produced this image mosaic, nicknamed the 'Whale Panorama,' two-thirds of the way to the summit of 'Husband Hill,' where the rover investigated martian rocks. On the right side of the panorama is a tilted layer of rocks dubbed 'Larry's Outcrop,' one of several tilted outcrops that scientists examined in April, 2005. They used spatial information to create geologic maps showing the compass orientation and degree of tilting of rock formations in the vicinity. Such information is key to geologic fieldwork because it helps establish if rock layers have been warped since they formed. In this case, scientists have also been studying the mineral and chemical differences, which show that some rocks have been more highly altered than others. In the foreground, in the middle of the image mosaic, Spirit is shown with the scientific instruments at the end of its robotic arm positioned on a rock target known as 'Ahab.' The rover was busy collecting elemental chemistry and mineralogy data on the rock at the same time that it was taking 50 individual snapshots with its five panoramic camera filters to create this stunning view of the martian scenery. The twin tracks of the rover's all-terrain wheels are clearly visible on the left. This mosaic of images spans about 220 degrees from left to right and is an approximate true-color rendering of the Mars terrain acquired through the panoramic camera's 750-, 530-, and 430-nanometer filters. Spirit collected these images from its 497th martian day, or sol, through its 500th sol (May 27 through May 30, 2005).

  4. Bisphenol A: a scientific evaluation.

    Science.gov (United States)

    Kamrin, Michael A

    2004-01-01

    Bisphenol A (BPA) is used in the production of high-volume polycarbonate and epoxy resin compounds found in a number of consumer products, including plastic bottles and the linings of canned goods. As a result of such applications, very small amounts of BPA can migrate into food and drink. In light of reports suggesting that low doses of BPA cause estrogenic effects in laboratory animals, concerns were raised about the safety of these consumer products, particularly plastic bottles used for feeding milk to babies. To evaluate the risk, if any, from BPA, investigations were undertaken to more precisely determine human exposure levels and more carefully study the validity of the low-dose effects reported. On the basis of the most realistic studies of BPA levels in food and drink, as well as in human urine, it has been estimated that human exposures, including those of children, are very low and range from about .001 to .1 mcg/kg body weight (bw)/day. The results of the additional toxicology studies indicated that the low-dose effects could not be consistently replicated. In light of this, a number of governments and agencies brought together independent expert panels to carefully evaluate the toxicologic studies and provide regulatory guidance. These panels came to a similar conclusion, namely, that low-dose effects have not been demonstrated. They also supported the acceptable daily intake levels previously calculated on the basis of high-dose effects shown in laboratory animals. Comparing these acceptable intakes with the best exposure estimates reveals that human doses of BPA from migration of the compound into food and drink are orders of magnitude lower than acceptable daily intakes. Thus, it is very unlikely that humans, including infants and young children, are at risk from the presence of BPA in consumer products. PMID:15520629

  5. A92

    Directory of Open Access Journals (Sweden)

    M. Mukhacheva

    2015-11-01

    Full Text Available This work is devoted to the actual problem of studying modern ideas about the systemic treatment of brain tumors, in particular on the implementation and effectiveness of modern methods of immunomodulation in neuro-oncology. The aim is to clarify the existence of patients with brain tumors immunosuppression, resulting in testimony to the development and application of methods of immunotherapy. Method of research consistent with the goal and objectives of the study, which included a dynamic examination of 32 operated patients with hemispheric brain gliomas. Cycloferon interferonogens from the group, which has antiviral and antitumor action potential was used as an immunomodulator us. It is of interest to determine the effectiveness of immunomodulatory action of cycloferon in patients with brain tumors in different phases of development of cancer. This work represents a scientific novelty and practical significance for solving urgent problems of neurology and neurosurgery – the study of the cycloferon drug, has proved its effectiveness in the reinforcement of clinical remission and increased the life expectancy of patients with brain tumors after surgery.

  6. A new

    Directory of Open Access Journals (Sweden)

    P. Upadhyay

    2016-07-01

    Full Text Available In this paper a population based evolutionary optimization methodology called firefly algorithm (FFA is applied for the optimization of system coefficients of the infinite impulse response (IIR system identification problem. FFA is inspired by the flash pattern and characteristics of fireflies. In FFA technique, behaviour of flashing firefly towards its competent mate is structured. In this algorithm attractiveness depends on brightness of light and a bright firefly feels more attraction for the brighter one. For this optimization problem, brightness varies inversely proportional to the error fitness value, so the position of the brightest firefly gives the optimum result corresponding to the least error fitness in multidimensional search space. Incorporation of different control parameters in basic movement equation results in balancing of exploration and exploitation of search space. The proposed FFA based system identification approach has alleviated from inherent drawbacks of premature convergence and stagnation, unlike genetic algorithm (GA, particle swarm optimization (PSO and differential evolution (DE. The simulation results obtained for some well known benchmark examples justify the efficacy of the proposed system identification approach using FFA over GA, PSO and DE in terms of convergence speed, identifying plant coefficients and mean square error (MSE fitness values produced for both same order and reduced order models of adaptive IIR filters.

  7. A Whale of A Controversy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Despite heavy international criticism,the Japanese refuse to end their national tradition of whale hunting When the Japanese whale-hunting fleet set sail for the Antarctic waters on November 18,the crew members must have known that their voyage would not be smooth sailing. Japan’s annual whaling program rou- tinely sets off a firestorm of protest from anti-whaling countries and organizations. In January 2006,Greenpeace’s icebreaker Arctic Sunrise collided with the Jaoanese

  8. A Response

    Directory of Open Access Journals (Sweden)

    W. Warren Wagar

    2015-08-01

    Full Text Available Let me begin by thanking everyone who commented on my ASA paper, "Toward a Praxis of World Integration," both those who were generally sympathetic to its thesis and those who were not. It is inconceivable to me that any two freethinking human beings living in our time could share the same preferred model of the good society. So of course I am not surprised that no one found every aspect of my vision appealing or that some found almost nothing to applaud. I would probably react to each of your utopias in muchthe same ways. Nonetheless, our species needs, perhaps more than anything else, to think together about where we want to go, and how, and why. Without tclos, how can we speak of praxis? And without praxis, what use is analysis? The point is to change the world and change it for the better.

  9. A whale of a problem

    Science.gov (United States)

    Showstack, Randy

    While the Makah Indian tribe recently killed a gray whale off the coast of the U.S. state of Washington, and Japan and Norway have threatened to bolt from the International Whaling Commission (IWC) over disagreements about commercial catches, on May 26, the U.S. commissioner to the IWC told delegates about another, and far more widespread, threat affecting cetaceans.Global environmental changes could jeopardize whale stocks throughout the world, said Commissioner James Baker, who also serves as administrator for the National Oceanic and Atmospheric Administration.

  10. A Mosque in a Mosque

    OpenAIRE

    Cantone, Cleo

    2006-01-01

    Une mosquée dans une mosquée. Quelques observations sur la mosquée de la rue Blanchot à Dakar et ses relations avec les autres mosquées pendant la période coloniale. — L’impact du colonialisme sur l’architecture sénégalaise a produit un nouveau type de mosquée. Construite à partir de matériaux durables et alliant l’architecture des églises à des éléments nord-africains, ce style semble avoir été utilisé pour perpétuer la notion de supériorité de l’islam « blanc », ou arabe, sur l’islam « noir...

  11. A Volumetric Flask as a Projector

    Science.gov (United States)

    Limsuwan, P.; Asanithi, P.; Thongpool, V.; Piriyawong, V.; Limsuwan, S.

    2012-01-01

    A lens based on liquid in the confined volume of a volumetric flask was presented as a potential projector to observe microscopic floating organisms or materials. In this experiment, a mosquito larva from a natural pond was selected as a demonstration sample. By shining a light beam from a laser pointer of any visible wavelength through the…

  12. Being a Parent with a Learning Disability: A Qualitative Study

    OpenAIRE

    Shewan, Laura

    2011-01-01

    This research portfolio aims to further explore the issues faced by parents with a learning disability. Firstly, a systematic review of qualitative research into the social support of parents with a learning disability is presented. This not only indicated that a range of social support is provided to parents with a learning disability and received with different perceptions, but also highlighted the need for further qualitative research in the area, to gain a better insight...

  13. Choosing a Breast Prosthesis: A Survivor's Perspective

    Science.gov (United States)

    ... Survivor’s Perspective Print to PDF Choosing a Breast Prosthesis: A Survivor’s Perspective Andrea Zinn June 16, 2015 · ... did you decide to wear a breast form/prosthesis rather than have a reconstruction? Andrea: After weighing ...

  14. Internship: A Transition From A Medical Student To A Doctor

    OpenAIRE

    2012-01-01

    The internship, a transition from a medical student to a doctor, is a period of one year after passing the final year exam of MBBS, where an intern works in various departments in a hospital. Doing so exposes them to the practical aspects of things they have studied during the four and a half year MBBS course. As a part of the physician’s team taking care of the patients s/he absorbs the skills to approach and management of the patients under direct supervision of their seniors. This also hel...

  15. A Russia e a segurança europeia

    OpenAIRE

    Gaspar, Carlos

    2005-01-01

    As relações entre a Rússia e a Europa, chave da segurança regional, mudaram profundamente com o fim da guerra fria. Desde 1991, o período de transição na reestruturação dos equilíbrios regionais, foi marcado por crises sucessivas - a crise latente entre a Rússia e a Ucrânia, a decomposição da antiga Jugoslávia e as divergências sobre a expansão da Aliança Atlântica - que criaram oportunidades de cooperação entre a Rússia e as potências ocidentais, e contribuiram para moldar ...

  16. Repurposing with a purpose: A story with a happy ending

    OpenAIRE

    Greaves, Lyn; Roller, Sibel; Bradley, Claire

    2010-01-01

    Abstract: The work reported here forms part of a UK Joint Information Systems Committee (JISC) funded project (BL4ACE) (http://bl4ace.tvu.ac.uk/). This project built on previous work that evaluated the effectiveness of a learning design to underpin academic competence in a Business Studies degree. A significant concern of the blended learning design was to scaffold independent learning activities by incorporating and reusing interactive Reusable Learning Objects (RLOs) within a Virtual Learni...

  17. A Pilocytic Astrocytoma Mimicking a Clinoidal Meningioma

    OpenAIRE

    Hong, Christopher S.; Lehman, Norman L.; Eric Sauvageau

    2014-01-01

    Pilocytic astrocytomas and meningiomas are benign, primary brain tumors that may involve the optic tract. Classically, the presence of a dural “tail” sign may differentiate a meningioma from other intracranial lesions. In this report, we describe a mass with the typical appearance of a clinoidal meningioma on magnetic resonance imaging (MRI) but postoperatively diagnosed as a pilocytic astrocytoma. This case illustrates the rare occurrence of a pilocytic astrocytoma mimicking a meningioma on ...

  18. A batuta da morte a orquestrar a vida

    Directory of Open Access Journals (Sweden)

    Altair Macedo Lahud Loureiro

    2008-12-01

    Full Text Available Com colocações de outros estudiosos da morte, teço e apresento apontamentos rápidos sobre a morte a organizar a vida. Esposo a idéia da necessidade da morte para que a vida tenha sentido nesta busca humana da completude. Endereço o olhar para uma situação especial de relação com a morte: a reação dos que ficam ao presenciar e sentir a morte de um dos seus idosos; daquele familiar, ou não, que assume o seu cuidado e acompanha o seu fim iminente; que presencia, humanamente impotente, a hora da solitária partida. Solitária morte, pois que exclusiva, própria daquele idoso do qual cuidava, do seu fim natural, por ser humano.

  19. A House For A River Rat

    OpenAIRE

    Matthews, David Stansfield

    2014-01-01

    This is a house situated by a river. It is a retreat, or a cabin, and is not occupied on a full time basis. Its form is an interpretation of a cube, and retains its general appearance. It is lifted off the ground to prevent damage when the river floods, and has a deep foundation to achieve stability on the loose floodplain soil. It has three levels, the first containing the main living areas, the second, a lofted space containing the bed and bath, and the third, a roof terrace. It is for two ...

  20. A diagrammatic categorification of a Clifford algebra

    OpenAIRE

    Tian, Yin

    2013-01-01

    We give a graphical calculus for a categorification of a Clifford algebra and its Fock space representation via differential graded categories. The categorical action is motivated by the gluing action between the contact categories of infinite strips.

  1. Helping a Child Manage a Chronic Illness

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_160011.html Helping a Child Manage a Chronic Illness Feeling they have control over their ... News) -- Children and teens who feel confident handling a chronic illness on their own appear better able ...

  2. Having a Whale of a Time

    Science.gov (United States)

    du Feu, Chris

    2009-01-01

    A classroom practical exercise exploring the reliability of a basic capture-mark-recapture method of population estimation is described using great whale conservation as a starting point. Various teaching resources are made available.

  3. Aplyzanzine A, a new dibromotyrosine derivative from a Verongida sponge.

    Science.gov (United States)

    Evan, T; Rudi, A; Ilan, M; Kashman, Y

    2001-02-01

    Aplyzanzine A (1), a novel bisdibromotyrosine derivative, has been isolated from the Indo-Pacific sponge Aplysina sp. Its structure was elucidated mainly on the basis of 1D and 2D NMR and MS spectroscopic data. PMID:11430007

  4. Vitamin A: a missing link in diabetes?

    OpenAIRE

    Trasino, Steven E.; Gudas, Lorraine J.

    2015-01-01

    Vitamin A has a critical role in embryonic development, immunity and the visual cycle. In recent years, evidence has demonstrated that vitamin A can also regulate metabolic pathways implicated in the pathogenesis of obesity and diabetes. This has increased interest in the possible antiobesity and antidiabetic properties of natural and synthetic vitamin A derivatives. However, whether vitamin A deficiency or aberrations in vitamin A metabolism contribute to the pathogenesis of diabetes is not ...

  5. Bacterial Sortase A as a drug target

    OpenAIRE

    Larsson, Caroline

    2012-01-01

    Sortase A is a housekeeping enzyme of Gram-positive bacteria that catalyses the anchoring of surface proteins to the bacterial peptidoglycan. The enzyme works to establish an interaction between bacteria and host cells and is essential for pathogenesis. This makes Sortase A a potential suitable target for inhibition, in order to treat bacterial infections. In this degree project Sortase A from Staphylococcus aureus was explored and potential inhibitors were investigated by performing enzyme a...

  6. A missed orthopaedic injury following a seizure: a case report

    Directory of Open Access Journals (Sweden)

    O'Connor-Read Laurence

    2007-05-01

    Full Text Available Abstract Numerous orthopaedic injuries can follow a seizure and are often diagnosed late. This is the first documented case of a missed bilateral anterior shoulder dislocation following a seizure. The possible reasons for the greater incidence of posterior dislocations are examined and why bilateral anterior dislocations following a seizure are so rare. The article discusses the reasons for the delay and highlights potential pitfalls and learning points for junior emergency department doctors.

  7. A stump appendicitis in a child: a case report

    OpenAIRE

    Jemaï Radhia; Sahli Sondes; Fitouri Fatma; Gasmi Manef; Hamzaoui Mourad

    2009-01-01

    Abstract Background Stump appendicitis is a delayed complication of appendectomy. It is rare and few cases reported in the paediatric literature. The authors report on another case in a child and focus on the diagnostic peculiarities of this entity. Case A 9-year-old boy with previous history of open appendectomy was admitted for a right lower quadrant pain with bilious vomiting and fever. Physical examination demonstrated tenderness in the right lower quadrant and guarding over the appendect...

  8. A recursive algorithm to compute a basis of a similarity

    OpenAIRE

    Garmendia Salvador, Luis; Recasens, Jordi; Salvador Alcaide, Adela

    2012-01-01

    Se definen conceptos y se aplica el teorema de Valverde para escribir un algoritmo que computa bases de similaridades. This paper studies sorne theory and methods to build a representation theorem basis of a similarity from the basis of its subsimilarities, providing an alternative recursive method to compute the basis of a similarity.

  9. A State-Run Enterprise: A Bane or a Boon?

    Directory of Open Access Journals (Sweden)

    Sungjune KIM

    2015-09-01

    Full Text Available In the less than 70 years since Korean liberation, Korea has grown to be one of the world's top five ship-owning countries in 2014. This can be attributed to a few factors such as government policy, Korea Shipping Corporation (KSC, hereafter and merchant marine officers. This paper will expound the true motivations of the establishment and the privatization of KSC in 1950 and in 1968, respectively. KSC, as Korea's national shipping company, sailed along a very unusual course of development. It was established in 1950 not to foster and develop Korea's shipping industry but to help alleviate the financial burdens of the fledgling Korean government. The main cause of privatizing KSC in 1968 was a purely political decision, not an economic one as it overlapped with the rapid growth period of the shipping industry in the world, as well as in Korea. In sum, KSC, a state-run enterprise, was a bane in the short run but a boon in the long run for both the Korean government and Korea's shipping industry. If we can believe KSC followed the ordinary sailing route as a state-run enterprise, we might develop a new opinion that the national shipping company might be a financial burden in a short period, but various benefits over a long period.

  10. A CLUSTER PAIR: A3532 AND A3530

    Energy Technology Data Exchange (ETDEWEB)

    Lakhchaura, Kiran; Singh, K. P. [Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India); Saikia, D. J. [National Centre for Radio Astrophysics, Tata Institute of Fundamental Research, Pune University Campus, Pune 411 007 (India); Hunstead, R. W., E-mail: kiran_astro@tifr.res.in [Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)

    2013-04-10

    We present a detailed study of a close pair of clusters of galaxies, A3532 and A3530, and their environments. The Chandra X-ray image of A3532 reveals the presence of substructures on scales of {approx}20'' in its core. XMM-Newton maps of the clusters show excess X-ray emission from an overlapping region between them. Spectrally determined projected temperature and entropy maps do not show any signs of cluster scale mergers either in the overlapping region or in any of the clusters. In A3532, however, some signs of the presence of galaxy scale mergers are visible, e.g., anisotropic temperature variations in the projected thermodynamic maps, a wide-angle-tailed (WAT) radio source in the brighter nucleus of its dumbbell brightest cluster galaxy, and a candidate X-ray cavity coincident with the northwestern extension of the WAT source in the low-frequency radio observations. The northwestern extension in A3532 seems either a part of the WAT or an unrelated diffuse source in A3532 or in the background. There is an indication that the cool core in A3532 has been disrupted by the central activity of the galactic nucleus. A reanalysis of the redshift data reinforces the close proximity of the clusters. The excess emission in the overlapping region appears to be a result of tidal interactions as the two clusters approach each other for the first time. However, we cannot rule out the possibility of the excess being due to the chance superposition of their X-ray halos.

  11. [A woman with a locked knee].

    Science.gov (United States)

    Boersma, A R; van Raay, J J A M

    2015-01-01

    A 25-year-old female presented with locking of the left knee after an assertiveness training. The MRI scan showed a bucket-handle tear of the medial meniscus. The medial meniscus was dislocated into the intercondylar fossa, in which the image of a second posterior cruciate ligament (PCL) was simulated. This is also called a 'double PCL sign'. PMID:26959734

  12. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Disorder What is Baby Bottle Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist When Should My Child First See a Dentist? Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral Health | ...

  13. Geogas - a tracer or a carrier?

    International Nuclear Information System (INIS)

    This report is a review of the literature about geogas and the migration of radioactive materials from a repository. The results indicate that nitrogen gas may cause a migration of plutonium colloids and other small particles. (64 refs.) (K.A.E.)

  14. A1-algebraic topology over a field

    CERN Document Server

    Morel, Fabien

    2012-01-01

    This text deals with A1-homotopy theory over a base field, i.e., with the natural homotopy theory associated to the category of smooth varieties over a field in which the affine line is imposed to be contractible. It is a natural sequel to the foundational paper on A1-homotopy theory written together with V. Voevodsky. Inspired by classical results in algebraic topology, we present new techniques, new results and applications related to the properties and computations of A1-homotopy sheaves, A1-homotogy sheaves, and sheaves with generalized transfers, as well as to algebraic vector bundles over affine smooth varieties.

  15. Niemann Pick type A, a case report

    OpenAIRE

    M. Qasemi; F. Mojtahedzadeh

    2006-01-01

    Niemann Pick type A is a very rare hereditary disease with an incidence 1 in 20000-40000 live birth, which is calassified as a shingolipidoses.The disease is marked by the abnormal accumulation of sphingomyelin in most tissues, secondary to sphingomylinase deficiency.The most clinical manifestations are:Splenohepatomegaly–cherry red maculae-neuropathologic findings .This is a case report of an infant with clinical manifestation of Niemann Pick disease type A.

  16. Bisphenol A polycarbonate as a reference material

    Science.gov (United States)

    Hilado, C. J.; Cumming, H. J.; Williams, J. B.

    1977-01-01

    Test methods require reference materials to standardize and maintain quality control. Various materials have been evaluated as possible reference materials, including a sample of bisphenol A polycarbonate without additives. Screening tests for relative toxicity under various experimental conditions were performed using male mice exposed to pyrolysis effluents over a 200-800 C temperature range. It was found that the bisphenol A polycarbonate served as a suitable reference material as it is available in large quantities, and does not significantly change with time.

  17. A Project Team: a Team or Just a Group?

    OpenAIRE

    Kateřina; Daniela,, Ghirardello; Martina (Author)

    2014-01-01

    This paper deals with issues related to work in either teams or groups. The theoretical part discusses a team and a group with regards to its definition, classification and basic distinction, brings in more on the typology of team roles, personality assessment and sociometric methods. The analytical part tests the project (work) team of a medical center represented in terms of personality and motivational types, team roles and interpersonal team relations concerning the willingness of coopera...

  18. A Project Team: A Team or Just a Group?

    OpenAIRE

    Katerina Hrazdilova Bockova; Daniela Maťovcikova

    2013-01-01

    This paper deals with issues related to work in either teams or groups. The theoretical part which discusses a team and a group with regards to its definition, classification and basic distinction brings in more on the typology of team roles, personality assessment and sociometric methods. The analytical part tests the project (work) team of a medical center represented in terms of personality and motivational types, team roles and interpersonal team relations concerning t...

  19. [A fetus is a person with a right to exist].

    Science.gov (United States)

    Bischofberger, E

    1989-12-27

    This article is the contribution of a Jesuit priest, a teacher of medical ethics at Uppsala, to a debate inspired by a Swedish official report "The pregnant woman and fetus--2 individuals. On fetal diagnostics. On late abortions." In a society which depends upon a structured consensus as much as Sweden does, the report has been criticized for not making clearer recommendations. The author points out that the ethical dilemmas involved are so complex that they cannot be treated from a simple either/or point of view. Fetal diagnostics, for example, serve the cause of life when the aim is to avoid abortion of a healthy fetus and make it possible to cure, even at the fetal stage, or to strengthen prospective parents' readiness to accept a handicapped child. The use of fetal diagnostic for sorting out damaged and sick fetuses, however, is selective abortion and implies a violation of the principle that all human life is of equal value. The question is no longer if one will have a child or not, but which child will one have. This collision of values has inspired so many polemic statements that it is worthwhile recalling that there is always a tension between the ethically desirable and the politically possible, The report has succeeded in formulating the ethical principles in spite of the impossibility of seeing them presented as concrete recommendations. Even so, Thomas Aquinas wrote in 13th century that one cannot always apply ethical rules to laws of society. That can lead to more evil than good. PMID:2607863

  20. A search for a new gauge boson A'

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Eric L. [William and Mary College

    2013-08-01

    In the Standard Model, gauge bosons mediate the strong, weak, and electromagnetic forces. New forces could have escaped detection only if their mediators are either heavier than order(TeV) or weakly coupled to charged matter. New vector bosons with small coupling {alpha}' arise naturally from a small kinetic mixing with the photon and have received considerable attention as an explanation of various dark matter related anomalies. Such particles can be produced in electron-nucleus fixed-target scattering and then decay to e{sup +}e{sup -} pairs. New light vector bosons and their associated forces are a common feature of Standard Model extensions, but existing constraints are remarkably sparse. The APEX experiment will search for a new vector boson A' with coupling {alpha}'/{alpha}{sub fs} > 6 × 10{sup -8} to electrons in the mass range 65MeV < mass A' < 550MeV. The experiment will study e{sup +}e{sup -} production off an electron beam incident on a high-Z target in Hall A at Jefferson Lab. The e{sup -} and e{sup +} will be detected in the High Resolution Spectrometers (HRSs). The invariant mass spectrum of the e{sup +}e{sup -} pairs will be scanned for a narrow resonance corresponding to the mass of the A'. A test run for the APEX experiment was held in the summer of 2010. Using the test run data, an A' search was performed in the mass range 175-250 MeV. The search found no evidence for an A' --> e{sup +}e{sup -} reaction, and set an upper limit of {alpha}'/{alpha}{sub fs} ~ 10{sup -6}.

  1. A Proposal for a Mindset of a Project Manager

    OpenAIRE

    Eriksson, Joakim; Hansen, Claus Thorp

    2008-01-01

    A company’s product strategy and its management of the product development process have been found to be key factors for a product’s success on the market [1]. Project managers of development projects need support to make process decisions and defining goals that are consistent with the business’s goals while bearing in mind the ability of the development team to deliver a product to the market that satisfies the customer’s expectations and needs [2]. Uncertainty is a part of the product deve...

  2. RelA: a tale of a stitch in time.

    Science.gov (United States)

    Korc, Murray

    2016-08-01

    Pancreatic ductal adenocarcinoma (PDAC) is a deadly cancer in which NF-κB pathways promote biological aggressiveness. In this issue of the JCI, Lesina et al. investigated the role of RelA, the p65 partner of p50 that together form the most common NF-κB complex, in the early stages of pancreatic malignant transformation and in established PDAC. By deleting Rela in the context of an oncogenic Kras-driven autochthonous model of PDAC, the authors demonstrated that RelA is a mediator of oncogene-induced senescence (OIS) and the senescence-associated secretory phenotype (SASP) that attenuates acinar-to-ductal metaplasia, pancreatic intraepithelial neoplasia (PanIN) formation, and PanIN progression to PDAC. Loss of the tumor-suppressor function of RelA in the early stages of Kras-driven pancreatic neoplastic transformation was associated with decreased OIS and SASP and a protumorigenic tumor microenvironment that harbored more M2 macrophages and myeloid-derived suppressor cells. The beneficial effects of RelA were mediated by increased expression of CXCL1 and its activation of CXCR2. By contrast, in advanced stages of Kras-driven murine PDAC, loss of p53 or p16 was associated with senescence bypass, and RelA deficiency in this context attenuated cancer cell proliferation and prolonged mouse survival, indicating that RelA enhances tumor progression in established PDAC. PMID:27454293

  3. A metaphysical journey in a comatose state.

    Science.gov (United States)

    Gimenez, R

    1992-01-01

    This paper is about the intense experience of being in the hospital in a comatose state resulting from an aneurysm with a massive brain hemorrhage and two subsequent surgeries. The event begins with a premonition of what will happen from a street name. The experience of brain surgeries, along with the fine care of the nurses, left me with a truly memorable impression. This paper describes the various feelings and strong emotions that I experienced while in a comatose state. It suggests that a patient in a comatose state can exist in a deep state of emotions close to ecstasy. The paper concludes with gratefulness to all the people who followed me step by step on this journey. PMID:1286457

  4. A toy model for a diatomic molecule

    Science.gov (United States)

    Hecker Denschlag, Johannes

    2016-08-01

    We introduce a toy model for a diatomic molecule which is based on coupling electronic and nuclear spins to a rigid rotor. Despite its simplicity, the model can be used scientifically to analyze and understand complex molecular hyperfine spectra. In addition, the model has educational value as a number of fundamental symmetries and conservation laws of the molecule can be studied. Because of its simple structure, the model can be readily implemented as a computer program with comparatively short computing times on the order of a few seconds.

  5. When a Family Requests a White Doctor.

    Science.gov (United States)

    Reynolds, Kimberly L; Cowden, John D; Brosco, Jeffrey P; Lantos, John D

    2015-08-01

    Parents sometimes request that a doctor of a particular race or ethnic group not care for their child. Such requests sometimes seem legitimate and other times seem offensive. The difference reflects a clash of fundamental values. Generally, we try to respect patient or parental preferences. Requests based on racist attitudes, however, do not seem worthy of respect. But where should we draw the line? In this ethics rounds, we present a situation in which parents requested a white doctor and analyze the ways in which doctors might think about and respond to such a request. PMID:26169433

  6. The a-MEU Model: A Comment

    OpenAIRE

    Jurgen Eichberger; Simon Grant; David Kelsey; Koshevoy, Gleb A.

    2009-01-01

    In [7] Ghirardato, Macheroni and Marinacci (GMM) propose a method for distinguishing between perceived ambiguity and the decision-maker's reaction to it. They study a general class of preferences which they refer to as invariant biseparable. This class includes CEU and MEU. They axiomatize a subclass of a-MEU preferences. If attention is restricted to finite state spaces, we show that any a-MEU preference relation, satisfies GMM's axioms if and only if a = 0 or 1, that is, the preferences mus...

  7. Building a Database for a Quantitative Model

    Science.gov (United States)

    Kahn, C. Joseph; Kleinhammer, Roger

    2014-01-01

    A database can greatly benefit a quantitative analysis. The defining characteristic of a quantitative risk, or reliability, model is the use of failure estimate data. Models can easily contain a thousand Basic Events, relying on hundreds of individual data sources. Obviously, entering so much data by hand will eventually lead to errors. Not so obviously entering data this way does not aid linking the Basic Events to the data sources. The best way to organize large amounts of data on a computer is with a database. But a model does not require a large, enterprise-level database with dedicated developers and administrators. A database built in Excel can be quite sufficient. A simple spreadsheet database can link every Basic Event to the individual data source selected for them. This database can also contain the manipulations appropriate for how the data is used in the model. These manipulations include stressing factors based on use and maintenance cycles, dormancy, unique failure modes, the modeling of multiple items as a single "Super component" Basic Event, and Bayesian Updating based on flight and testing experience. A simple, unique metadata field in both the model and database provides a link from any Basic Event in the model to its data source and all relevant calculations. The credibility for the entire model often rests on the credibility and traceability of the data.

  8. A Project Team: a Team or Just a Group?

    Directory of Open Access Journals (Sweden)

    Kateřina

    2014-06-01

    Full Text Available This paper deals with issues related to work in either teams or groups. The theoretical part discusses a team and a group with regards to its definition, classification and basic distinction, brings in more on the typology of team roles, personality assessment and sociometric methods. The analytical part tests the project (work team of a medical center represented in terms of personality and motivational types, team roles and interpersonal team relations concerning the willingness of cooperation and communication. The main objective of this work is to verify the validity of the assumptions that the analyzed team represents a very disparate group as for its composition from the perspective of personality types, types of motivation, team roles and interpersonal relations in terms of the willingness of cooperation and communication. A separate output shall focus on sociometric investigation of those team members where willingness to work together and communicate is based on the authors’ assumption of tight interdependence.

  9. Broadcasting a message in a parallel computer

    Science.gov (United States)

    Berg, Jeremy E.; Faraj, Ahmad A.

    2011-08-02

    Methods, systems, and products are disclosed for broadcasting a message in a parallel computer. The parallel computer includes a plurality of compute nodes connected together using a data communications network. The data communications network optimized for point to point data communications and is characterized by at least two dimensions. The compute nodes are organized into at least one operational group of compute nodes for collective parallel operations of the parallel computer. One compute node of the operational group assigned to be a logical root. Broadcasting a message in a parallel computer includes: establishing a Hamiltonian path along all of the compute nodes in at least one plane of the data communications network and in the operational group; and broadcasting, by the logical root to the remaining compute nodes, the logical root's message along the established Hamiltonian path.

  10. [A simulation exercise in a flu clinic].

    Science.gov (United States)

    Barthe, Juliette; Aubert, Jean-Pierre; Lecapitaine, Anne-Lise; Lecompte, Françoise; Szwebel-Chikli, Céline

    2011-01-01

    A simulation exercise aimed at assessing the management and provision of ambulatory care in the context of a highly pathogenic influenza pandemic was conducted in a specifically dedicated consultation center (Centre de Consultation Dédié (CCD) à la grippe) based on official French guidelines. The exercise was carried out in a school in Paris equipped to simulate a "flu clinic". 3 practitioners provided treatment lasting 2 hours to nursing students acting as patients. The exercise highlighted a number of major organizational issues. Staff were found to be unable to manage the center and to perform patient transfers; face masks were not routinely and consistently worn by doctors and patients; and communication between professionals within the clinic was limited. The exercise showed that much remains to be done to ensure that "flu clinics" are effective and functional. The results suggest that the exercise will need to be repeated on a larger scale and over a longer period. PMID:22365047

  11. A porous metal cathode (a thermoemission converter)

    Energy Technology Data Exchange (ETDEWEB)

    Kozlov, V.I.; Avdeyev, V.Ye.

    1983-01-01

    The porous metallic cathode, which contains a body and the basic sponge attached to it with an active substance, made in the form of a base with an emitting projection, is distinguished by the fact that in order to increase the service life of the cathode, the based sponges on the side opposite the projection have a groove in which the replenishing chamber made of a difficulty fusible metal and filled with a mixture of tungsten and an active substance with a porosity of 35 to 80 percent which is open towards the projection is positioned, where the transverse cross section of the replenishing chamber intersects the transverse cross section of the projection, while the porosity of the basic sponge is 24 to 26 percent. The cathode is distinguished by the fact that a screen made of a difficultly fusible metal is installed on the facial surface with an opening for the projection and is connected with the body and with this surface.

  12. A Cultural Sexuality or a Sexual Culture?

    OpenAIRE

    Vandermeersch, Patrick

    1990-01-01

    P. Vandermeersch, A Cultural Sexuality or a Sexual Culture? In: F. VAN DE VIJVER & G. HUTSCHEMAEKERS (ed.), The Investigation of Culture. Current Issues in Cultural Psychology, Tilburg, Tilburg University Press, 1990, 43-58.

  13. A simple model of a swing

    Science.gov (United States)

    Mayer, V. V.; Varaksina, E. I.

    2016-07-01

    The paper presents a simple model of a swing meant for undergraduates’ educational experiments. The purpose of these experiments is the experimental study of physical principles of self-oscillations, free, forced and parametric oscillations. The model contains a pendulum. A coil with a movable steel core serves as its load. A neodymium magnet is placed at the lower end of the core. A magnetically operated sealed switch is stationed under the magnet at the equilibrium position of the pendulum. The switch is connected in series with the coil and a battery. If we displace the pendulum from the equilibrium position, the pendulum makes undamped oscillations. The system receives energy every time the core is drawn into the coil at the lower position of the pendulum.

  14. Ankylosing Spondylitis: a Reflection and a Question

    Directory of Open Access Journals (Sweden)

    Annia Deysi Hernández Martín

    2014-07-01

    Full Text Available Ankylosing spondylitis is a chronic inflammatory disease that affects the synovial membrane, joint entheses and para-articular structures of the spine, including the sacroiliac joints and limbs. We present a case of ankylosing spondylitis that had evolved for 12 years despite the relatively early diagnosis and treatment, showing flexion deformity and limitation of spinal movements. On radiological examination an early evolution to ankylosis was observed, which motivated us to make a reflection and a question.

  15. A masonic poem on a masonic opera?

    OpenAIRE

    Sanz Sainz, Inmaculada

    1998-01-01

    Estudio del poema Logic and "The Magic Flute", escrito por Marianne Moore (Kirkwood, Missouri. 1887-New York. 1972) y publicado en su libro de poemas Like a Bulwark (1956). Se analiza el poema tomando como punto de partida el libreto de la ópera de W.A. Mozart Die Zauberflotë, y se ofrece una interpretación del mismo a la luz de la simbología que aparece en este.

  16. A little knowledge is a dangerous thing

    OpenAIRE

    Robbins RA

    2012-01-01

    No abstract available. Article truncated at 150 words. An article entitled “A Comprehensive Care Management Program to Prevent Chronic Obstructive Pulmonary Disease Hospitalizations: A Randomized, Controlled Trial” from the VA cooperative studies program was recently published in the Annals of Internal Medicine (1). This article describes the BREATH trial mentioned in a previous editorial (2). BREATH was a randomized, controlled, multi-center trial performed at 20 VA medical centers comparin...

  17. A new hospital library: a marketing opportunity.

    OpenAIRE

    Walker, M E

    1995-01-01

    A new or remodeled library presents a unique marketing opportunity for the hospital librarian. Furthermore, a well-designed library markets itself through its convenience, attractiveness, and ease of use. A marketing approach to library planning takes into account needs of users and of library staff and considers the librarian's relations with the architect as well as with hospital employees. This paper describes ways to combine library planning with marketing techniques and specifies aspects...

  18. Persistence of a pinch in a pipe

    OpenAIRE

    Mahadevan, L.; Vaziri, A.; Das, Moumita

    2006-01-01

    The response of low-dimensional solid objects combines geometry and physics in unusual ways, exemplified in structures of great utility such as a thin-walled tube that is ubiquitous in nature and technology. Here we provide a particularly surprising consequence of this confluence of geometry and physics in tubular structures: the anomalously large persistence of a localized pinch in an elastic pipe whose effect decays very slowly as an oscillatory exponential with a persistence length that di...

  19. Morphing a Plasmonic Nanodisk into a Nanotriangle

    OpenAIRE

    Schmidt, Franz P.; Ditlbacher, Harald; Hofer, Ferdinand; Krenn, Joachim R; Hohenester, Ulrich

    2014-01-01

    We morph a silver nanodisk into a nanotriangle by producing a series of nanoparticles with electron beam lithography. Using electron energy loss spectroscopy (EELS), we map out the plasmonic eigenmodes and trace the evolution of edge and film modes during morphing. Our results suggest that disk modes, characterized by angular order, can serve as a suitable basis for other nanoparticle geometries and are subject to resonance energy shifts and splittings, as well as to hybridization upon morphi...

  20. A microcomputer for a packet switched network

    International Nuclear Information System (INIS)

    The Bubble Chamber Research Group of the Rutherford and Appleton Laboratory has a large film analysis facility. This comprises 16 digitising tables used for the measurement of bubble chamber film. Each of these tables has an associated microcomputer. These microcomputers are linked by a star structured packet switched local area network (LAN) to a VAX 11/780. The LAN, and in particular a microcomputer of novel architecture designed to act as the central switch of the network, is described. (author)

  1. Radioactivity: a history of a mysterious science

    International Nuclear Information System (INIS)

    In this work is summarized in french the book 'Radioactivity: a history of a mysterious science' written by Marjorie C. Malley. The fascinating history of radioactivity is at first presented in a way that is both accessible and appealing to the general reader. Not merely a historical account, the book examines philosophical issues connected with radioactivity, and relates its topics to broader issues regarding the nature of science. (O.M.)

  2. Raising a Fit Preschooler

    Science.gov (United States)

    ... skills and coordination to ride a tricycle or chase a butterfly. Preschoolers also are discovering what it ... something to find, like a red door, a cat, a flag, and something square. Sing songs or ...

  3. A review of a pleural service.

    Science.gov (United States)

    Aujayeb, A; Parker, S; Bourke, S; Miller, J; Cooper, D

    2016-12-01

    This paper reviews the organisation and outcomes of a pleural service, specifically geared towards the management of malignant pleural effusions, in a district general hospital in the north east of England. We summarise the evidence behind local anaesthetic thoracoscopy and indwelling pleural catheters. We then summarise the review of our service, including a discussion around complications. PMID:27092367

  4. Teaching a Course around a Textbook.

    Science.gov (United States)

    Healey, Mick; Ilbery, Brian

    1993-01-01

    Outlines the advantages and disadvantages of using a single textbook in a college-level economic geography course. Argues that, if a course text is used thoughtfully, the advantages can outweigh the disadvantages. Asserts that students must take greater responsibility for their own learning and develop independent inquiry skills. (CFR)

  5. A minimal model of a tidewater glacier

    NARCIS (Netherlands)

    Oerlemans, J.; Nick, Faezeh Maghami

    2005-01-01

    We propose a simple, highly parameterized model of a tidewater glacier. The mean ice thickness and the ice thickness at the glacier front are parameterized in terms of glacier length and, when the glacier is calving, water depth. We use a linear relation between calving rate and water depth. The cha

  6. When a regulation becomes a learning process

    DEFF Research Database (Denmark)

    Nunez, Heilyn Camacho; Cespedes, Paula

    Adoption and effective use of information and communication technology (ICT) becomes a need for organizations of any size and type, however, ICT adoption is still a challenge for organizations, its implementation must be a strategic decision that involves design, delivery and use of software...... small consulting company from Costa Rica, is using action learning to implement COBIT in the financial sector in Costa Rica....

  7. A modified total synthesis of cystothiazole A

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A modified total synthesis of cystothiazole A is described. In this synthetic strategy, a one-step transformation of acylated oxazolidinone to β-ketoester has been successfully applied, thus making the synthetic route more efficient. This method may also be potentially applied in synthesis of other related β-substituted-β-methoxyl acrylates (bb-MOAs).

  8. Once a Nightmare, Always a Nightmare?

    Science.gov (United States)

    Picchioni, Dante; DeBrule, Daniel S.

    2005-01-01

    While counterintuitive, there is evidence that some nightmares may serve a beneficial function. The theory behind this idea is presented within the context of a continuity hypothesis of dreaming where the negative emotions presented in a nightmare can lead to psychosocial development, just as some negative experiences do so during wake. The…

  9. A Bayesian Bootstrap for a Finite Population

    OpenAIRE

    Lo, Albert Y.

    1988-01-01

    A Bayesian bootstrap for a finite population is introduced; its small-sample distributional properties are discussed and compared with those of the frequentist bootstrap for a finite population. It is also shown that the two are first-order asymptotically equivalent.

  10. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... a Composite Resin (White Filling)? Why is Oral Health Important for Men? How Do I Care for My Child's Baby Teeth? What is Orofacial Pain? Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  11. A. F. Ames, Village Schoolmaster. A Memoir.

    Science.gov (United States)

    Ames, Edward C.

    This booklet sketches the life, educational theories, and accomplishments of Albert F. Ames (1888-1931). Ames was trained as a mathematician, and served six years as a mathematics teacher in Canada before becoming superintendent of schools in Riverside, Illinois. He co-authored five mathematics textbooks with J. A. McLellan. These texts,…

  12. A Method of Operating a Fuel Cell

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a method of determining the net water drag coefficient (rd) in a fuel cell. By measuring the velocity of the fluid stream at the outlet of the anode, rd can be determined. Real time monitoring and adjustments of the water balance of a fuel cell may be therefore...

  13. Sterilization: A Conference and a Report.

    Science.gov (United States)

    Dillingham, Brint

    1978-01-01

    This article continues a series on Native American sterilization, based on a conference of the National Council of Churches' Interreligious Foundation for Community Organization (IFCO). Also included are an article and a report by the American Civil Liberties Union. (Author/RTS)

  14. "Score Choice": A Tempest in a Teapot?

    Science.gov (United States)

    Hoover, Eric

    2009-01-01

    A new option that allows students to choose which of their test scores to send to colleges has generated renewed criticism of the College Board. College Board officials tout the option, called Score Choice, as a way to ease test taker anxiety. Some prominent admissions officials have publicly described Score Choice as a sales tactic that will…

  15. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Decay? Check Menstrual Calendar for Tooth Extraction The History of Dental Advances Men: Looking for a Better Job? Start by Visiting the Dentist Learn what those dental words mean. The Life of a Tooth games Home | InfoBites | Find a ...

  16. A Model Technology Educator: Thomas A. Edison

    Science.gov (United States)

    Pretzer, William S.; Rogers, George E.; Bush, Jeffery

    2007-01-01

    Reflecting back over a century ago to the small village of Menlo Park, New Jersey provides insight into a remarkable visionary and an exceptional role model for today's problem-solving and design-focused technology educator: Thomas A. Edison, inventor, innovator, and model technology educator. Since Edison could not simply apply existing knowledge…

  17. A microfluidic device with a diffusion barrier

    DEFF Research Database (Denmark)

    2014-01-01

    The invention provides a microfiuidic device for macromoiecuie amplification by sequential addition of liquid reagents. The device of the invention comprises a chip forming a plurality of reaction chambers each extending between an inlet and an outlet, each inlet being in fluid communication with...

  18. A case of tripody in a pigeon

    International Nuclear Information System (INIS)

    In a pigeon of the breed ''Thuringian White Bib'' a stunted third leg was found, which was attached to the left of the ventral cloacal aspect. A disturbance of the embryonic development at the third to fourth day of incubation was thought to be the cause of this anomaly

  19. Teratogenia da vitamina A Vitamin A teratogenicity

    Directory of Open Access Journals (Sweden)

    Maria Helena de Castro Chagas

    2003-09-01

    Full Text Available A vitamina A é essencial à preservação e ao funcionamento normal dos tecidos, assim como, ao crescimento e desenvolvimento. No humano há evidência indireta que a vitamina A em excesso, durante as primeiras semanas de gestação é teratogênica. Do contrário, não há dúvidas sobre os efeitos deletérios, de uma alimentação carente neste micronutriente e sobre a disponibilidade do conhecimento técnico para evitá-los. A preocupação com o fato de que a vitamina A conduziria a teratogenia em humanos, tem retardado a implementação de programas de combate a carência de vitamina A, atingindo principalmente os programas de enriquecimento de alimentos. A literatura é controvertida e dispõe de poucas informações sobre as doses para suplementação de gestantes. Como o retinol circulante materno é controlado homeostaticamente após o consumo de alimentos fonte de vitamina A, espera-se a mesma resposta metabólica após o consumo de alimentos fortificados, indicando que não há risco de teratogenia. Consequentemente, parece altamente improvável que o consumo de alimentos enriquecidos ou de suplementos de vitamina A pré-formada, nas doses unitárias habituais, tenha efeito teratogênico no homem.The vitamin A is essential to the preservation and the normal functioning of tissues, as well as, to the growth and development. In the human being it has indirect evidence that the vitamin A in excess, during the first weeks of gestation is teratogenic. Of the opposite, it does not have doubts on the deleterious effect, of a devoid feeding in this micronutrient and on the availability of the knowledge technician to prevent them. The concern with the fact of that the vitamin A would lead it the teratogenicity in human beings, has delayed the implementation of combat programs the vitamin A lack, mainly reaching the programs of food enrichment. Literature is controverted and makes use of few information on the doses for supplementation of

  20. A reversible conversion between a skyrmion and a domain-wall pair in a junction geometry

    OpenAIRE

    Zhou, Y.; Ezawa, M

    2014-01-01

    A skyrmion is a topological texture in the continuum field theory. Recent experimental observation of skyrmions in chiral magnet evokes a flourish of its extensive study. Skyrmion is expected to be a key component of the next generation spintronics device called skyrmionics. On the other hand, there is a well established memory device encoded by a sequence of domain walls. A skyrmion carries a topological number, whereas a domain wall does not. Nevertheless, we show a conversion is possible b...

  1. A Psychological Factor Affecting a Cardiac Condition in a Psychotherapist

    Directory of Open Access Journals (Sweden)

    R Waxman

    2009-03-01

    Full Text Available It has been established that intense emotions can affect the development and course of cardiac arrhythmias. This study sought to convey that a lack of expression of emotion can also have an effect on arrhythmias. A psychotherapist with Idiopathic Ventricular Fibrillation and an Implantable Cardioverter Defibrillator measured his rate of Premature Ventricular Contractions using a Holter monitor during three separate six-week periods and in three domains: A work days vs. off days, B a 27 hour work week vs. 22 hour work week, and C in 5 different modalities including 1 Meeting with department head 2 Individual psychotherapy with patients 3 Group therapy with patients 4 Supervision of residents 5 Personal psychoanalysis. The results showed more than a 3-fold increase of arrhythmogenic activity during the 27-hour work week vs. 22 and a 5-fold increase in arrhythmogenic activity on work days compared to days off. Department Head meetings were found to be most arrhythmogenic and personal psychoanalysis was least. The data suggest that the psychiatrist’s lack of emotional expression in his clinical work has been demonstrated to markedly worsen his arrhythmia. The results also point to the potential ameliorating effects of the therapist’s own psychotherapy.

  2. A PURCHASING DECISION: SELECTING A SUPPLIER FOR A CONSTRUCTION COMPANY

    Institute of Scientific and Technical Information of China (English)

    Ozden BAYAZIT; Birsen KARPAK; Ayhan YAGCI

    2006-01-01

    Supplier selection is one of the most crucial activities performed by organizations because of its strategic importance. Supplier selection is a multi-objective problem involving both quantitative and qualitative criteria. Over the years a number of quantitative approaches have been tried. Although the Analytic Hierarchy Process (AHP) has previously been used in supplier selection problems, one major weakness of the application-oriented AHP literature is that it tends to focus on the mechanics of AHP instead of on the theoretical and practical implications associated with finding a solution. Though it is one of the most extensively used Multiple Criteria Decision Analysis methodologies, our literature search indicated that most studies found the best solution and stopped there, ignoring sensitivity analysis. Performing sensitivity analysis is very important for practical decision making, sometimes even as important as finding the best solution. In this paper for the first time a comprehensive application of AHP for a real-world case is presented along with sensitivity analysis in choosing the best suppliers for a Turkish construction company. As a result of this study the company decided to allocate the order quantities between the two top suppliers.

  3. Pellets - A fuel with a future

    International Nuclear Information System (INIS)

    This special brochure presents a series of articles on the topic of wood pellets as a fuel of the future. Dr. Walter Steinmann, director of the Swiss Federal Office of Energy (SFOE) introduces the topic, stressing that the Swiss Confederation and the Cantons are supporting efforts to increase the sustainable use of wood fuels. Further articles take a closer look at pellets and their form. Pellets-fired heating units are introduced as a viable alternative to traditional oil-fired units. Tips are presented on the various ways of storing pellets. Quality-assurance aspects are examined and manufacturers and distributors of wood pellets are listed. A further article takes a closer look at a large Swiss manufacturer of pellets and describes the production process used as well as the logistics necessary for the transportation of raw materials and finished products. The brochure also presents a selection of pellet ovens and heating systems from various manufacturers. A further article illustrates the use of pellets as a means of heating apartment blocks built to the MINERGIE low-energy-consumption standard. In the example quoted, the classic combination of solar energy for the pre-heating of hot water and pellets for the central heating and hot water supply is used. The use of a buried spherical tank to store pellets - and thus the saving of space inside the building - is described in a further article that takes a look at the refurbishment of the heating system in a single-family home. Finally, various contributions presented at the Pellets Forum held in Berne in November 2003 are summarised in a short article

  4. Eurasian Union: A Utopia, a Dream or a Coming Reality?

    Directory of Open Access Journals (Sweden)

    Tuğçe Varol SEVIM

    2013-11-01

    Full Text Available Twenty years passed after the dissolution of the USSR and the re-birth of Russian Federation and Central Asian states in the world arena in such a unipolar world. Since the rise of Vladimir Putin to power Russia resists on unipolar system and sees that as a treat to its security. Hence, Kremlin perceives that the economic strength is the sine qua non for the future of Russia in order to sustain a Big Power status not only in its region but also in the world. In 2011, Russia, Belarus and Kazakhstan have achieved to form a Customs Union among them and invited all the states in the region to join the organization. There were thesis which mainly argued that Russia would no longer be a “power” in the Central Asia and could only be a regional power just in case of maintaining of its own unity. However, the circumstances have changed in the region accordingly Russian weight as a result of the new conjuncture. In 2012, Russia had a new presidential election and Putin returned to Kremlin as President himself. It has been understood from his words that Kremlin's new strategy to be focused on creating a Eurasian Union including Kyrgyzstan and Tajikistan at the first stage. It is aimed to analyze in this study that whether this project could be successful and if so, what could be the impacts on world order in terms of competition between Russia, the United States and China also. And finally, what could be the result of such an organization for the Russia.

  5. Homenagem a Ecléa Bosi

    Directory of Open Access Journals (Sweden)

    Marilena Chauí

    2008-03-01

    Full Text Available Neste ensaio, buscamos a principal contribuição de Ecléa Bosi para a Psicologia Social, qual seja, a relação entre teoria, método e técnicas de pesquisa e militância social, política e cultural, a partir da definição da psicologia como fenomenologia dos atos expressivos e da relação de amizade entre o pesquisador e o pesquisado como pessoa.

  6. Prospects for a group A streptococcal vaccine.

    Science.gov (United States)

    McMillan, David J; Chhatwal, Gursharan S

    2005-02-01

    Group A streptococcal (GAS) infections are associated with a number of human diseases, including pharyngitis, impetigo, necrotizing fasciitis, streptococcal toxic shock syndrome and rheumatic heart disease. An increase in the incidence of severe GAS infections in Western countries, and the awareness of the burden of GAS-associated diseases in developing nations, which remains high in spite of the availability of antibiotics, has provided the impetus for development of a safe and efficacious GAS vaccine. This has focused on the M protein, a major GAS virulence factor, however, with the publication of several GAS genomes, a number of non-M vaccine candidates are now under investigation. PMID:15732524

  7. Josephine Baker: A Chanteuse and a Fighter

    Directory of Open Access Journals (Sweden)

    Konomi Ara

    2010-03-01

    Full Text Available

    This excerpt is from her newly-published biography of Josephine Baker, “A Fighting Diva.” It tells the intriguing story of Baker’s travels to Japan, her close friendship with the Japanese humanitarian Miki Sawada, and her adoption of a pair of Japanese orphans. Even after she achieved celebrity in France, Baker’s experience as a Black American led her to develop an antiracist philosophy at a worldwide level, and she combined political militancy in the public sphere with a personal commitment through the formation of an international multiracial household of children, the “Rainbow Tribe.”

  8. Josephine Baker: A Chanteuse and a Fighter

    Directory of Open Access Journals (Sweden)

    Konomi Ara

    2010-03-01

    Full Text Available This excerpt is from her newly-published biography of Josephine Baker, “A Fighting Diva.” It tells the intriguing story of Baker’s travels to Japan, her close friendship with the Japanese humanitarian Miki Sawada, and her adoption of a pair of Japanese orphans. Even after she achieved celebrity in France, Baker’s experience as a Black American led her to develop an antiracist philosophy at a worldwide level, and she combined political militancy in the public sphere with a personal commitment through the formation of an international multiracial household of children, the “Rainbow Tribe.”

  9. Comparing a Linguistic and a Stochastic Tagger

    CERN Document Server

    Samuelsson, C; Samuelsson, Christer; Voutilainen, Atro

    1997-01-01

    Concerning different approaches to automatic PoS tagging: EngCG-2, a constraint-based morphological tagger, is compared in a double-blind test with a state-of-the-art statistical tagger on a common disambiguation task using a common tag set. The experiments show that for the same amount of remaining ambiguity, the error rate of the statistical tagger is one order of magnitude greater than that of the rule-based one. The two related issues of priming effects compromising the results and disagreement between human annotators are also addressed.

  10. Comparing a Linguistic and a Stochastic Tagger

    OpenAIRE

    Samuelsson, Christer; Voutilainen, Atro

    1997-01-01

    Concerning different approaches to automatic PoS tagging: EngCG-2, a constraint-based morphological tagger, is compared in a double-blind test with a state-of-the-art statistical tagger on a common disambiguation task using a common tag set. The experiments show that for the same amount of remaining ambiguity, the error rate of the statistical tagger is one order of magnitude greater than that of the rule-based one. The two related issues of priming effects compromising the results and disagr...

  11. Creating a website for a small business

    OpenAIRE

    Assefa, Bethelhem

    2011-01-01

    This Bachelor thesis is about creating a website for a small business. Santakehys Oy is the company who commissioned this thesis. Santakehys Oy used to have a website under the domain name ‘www.monalisa.fi’. This domain name is taken by another business and does not exist anymore under Santakehys. The current owner of the company wants to strength the business so that he decided to have a new website. This thesis focused on two main thing. The first one is creating (developing) a website f...

  12. A Beautiful Blonde: a Nash coordination game

    OpenAIRE

    Anderson, Simon P.; Maxim Engers

    2002-01-01

    In a memorable scene from the …lm ”A Beautiful Mind,” John Nash explains to his friends how to direct their attentions to women in a bar. Game theorists who have seen the …lm point out that the proposed solution is not a Nash equilibrium. Here we determine the Nash equilibria to the attention game. The symmetric mixed strategy equilibrium has resembles a common property resource problem. It has perverse comparative static properties that are not borne out by experimental data. Finally, we dis...

  13. To be a Barbie - a feasible dream

    OpenAIRE

    Brito, Maria; Gama, Maria Gabriela

    2012-01-01

    From friend to partner Barbie was winning a legion of fans, and there are many girls who idealize seem like a doll. The utopia of perfect body leads to questioning the immersion of technique in life, i.e., the junction of the bios with technè, the hybridity between the organic and the inorganic. The new technical possibilities provide a number of opportunities, and what was until then an aspiration, volition, is realized today in a right and a duty that is claimed. All differences are convert...

  14. A Wimba Way, A Wimba Way

    OpenAIRE

    Miller, Katherine; Taylor, Sally; Beck, Charlotte

    2010-01-01

    Wimba Classroom, like other online teaching tools, gives us a way to connect to our learners at a distance. This software can be used to share desktops, PowerPoint presentations, polls and more. Come and see a demonstration of the software and hear how we’re using Wimba Classroom to teach health care practitioners in a distance education program, undergraduate students in a first-year biology course and participants in an online RefWorks workshop. We’ll also talk about our “Train the Trainer”...

  15. Redefining disability: a rejoinder to a critique

    Directory of Open Access Journals (Sweden)

    Solveig Magnus Reindal

    2010-01-01

    Full Text Available Recently, scholars have argued that disability activists' redefinition of disability' as a social problem, rather than a medical problem, is maleficent, unjust, and inconsistent. It seems that the discussion on whether disability is a medical or a social category is not settled and that disability is an essentially contested concept. However, the question is: What is the social aspect in disability? It appears that there is some confusion as to what the social is in a social definition of disability. The article pursues possible reasons for this confusion by investigating the critique of the social model. This is followed by a discussion on what a possible space for the social might be in a social definition of disability. Such a space is illuminated by using the framework of the World Health Organization's International Classification of Functioning Disability and Health (ICF. The article suggests that disability as a social category is not inconsistent if reframed within a social relational model of disability.http://dx.doi.org/10.5324/eip.v4i1.1744

  16. A Spectrum is Worth a Thousand Pictures

    Science.gov (United States)

    Gelderman, Richard F.

    2006-12-01

    A wise astronomer once pointed out that if a picture is worth a thousand words, then a spectrum is worth a thousand pictures. Unfortunately, spectra are rarely emphasized in the introductory astronomy courses and few students exit such a course with any meaningful understanding or appreciation of spectroscopy. Part of the problem is lack of background knowledge; the typical introductory astronomy student has little experience with spectroscopy or atomic physics. Another issue is that spectra are not pretty pictures and are not intuitively understandable. We present and discuss a series of “minds-on” exercises and activities built into a college-level “stars, galaxies, and cosmology” intro astronomy course. The lessons are structured to help students improve their ability to recognize patterns and improve their ability to really see the details in front of them. Another goal is for students to realize there is “more than meets the eye” to learn how to discover “hidden” diagnostics, such as different sources of light their eyes see as white light. A curriculum that emphasizes spectroscopy also provides the opportunity to stress the story of the “Harvard Women,” a tale that bridges gender gaps and often humanizes scientists in the eyes of non-science majors. Finally, with a solid foundation in spectroscopy, students are better prepared to understand exciting topics such as Hubble’s Law and the importance of primordial nucleosynthesis.

  17. A Random Laser as a Dynamical Network

    CERN Document Server

    Höfner, M; Henneberger, F

    2013-01-01

    The mode dynamics of a random laser is investigated in experiment and theory. The laser consists of a ZnCdO/ZnO multiple quantum well with air-holes that provide the necessary feedback. Time-resolved measurements reveal multimode spectra with individually developing features but no variation from shot to shot. These findings are qualitatively reproduced with a model that exploits the specifics of a dilute system of weak scatterers and can be interpreted in terms of a lasing network. Introducing the phase-sensitive node coherence reveals new aspects of the self-organization of the laser field. Lasing is carried by connected links between a subset of scatterers, the fields on which are oscillating coherently in phase. In addition, perturbing feedback with possibly unfitting phases from frustrated other scatterers is suppressed by destructive superposition. We believe that our findings are representative at least for weakly scattering random lasers. A generalization to random laser with dense and strong scattere...

  18. A numerical model for a room fire

    International Nuclear Information System (INIS)

    A simple room fire experiment has been used as a development case for numerical fire simulation based on computational fluid dynamics. Experimental values (Steckler et al. 1982) are used to verify simulation. A limited method to use a flee flow boundary condition has been described (flow is assumed to be oblique to the boundary). Description of buoyancy terms, atmospheric pressure and additional terms of turbulence due to buoyancy are also given. Fire source is described as a predefined heat source. Comparison to the experiments shows that flow velocity at the room door, which is the only opening to the room, can be predicted with a good and temperature with a moderate accuracy. (au) (3 refs., 13 figs., 2 tabs.)

  19. A vision system for a Mars rover

    Science.gov (United States)

    Wilcox, Brian H.; Gennery, Donald B.; Mishkin, Andrew H.; Cooper, Brian K.; Lawton, Teri B.; Lay, N. Keith; Katzmann, Steven P.

    1988-01-01

    A Mars rover must be able to sense its local environment with sufficient resolution and accuracy to avoid local obstacles and hazards while moving a significant distance each day. Power efficiency and reliability are extremely important considerations, making stereo correlation an attractive method of range sensing compared to laser scanning, if the computational load and correspondence errors can be handled. Techniques for treatment of these problems, including the use of more than two cameras to reduce correspondence errors and possibly to limit the computational burden of stereo processing, have been tested at JPL. Once a reliable range map is obtained, it must be transformed to a plan view and compared to a stored terrain database, in order to refine the estimated position of the rover and to improve the database. The slope and roughness of each terrain region are computed, which form the basis for a traversability map allowing local path planning. Ongoing research and field testing of such a system is described.

  20. SUPERNOVA 1987A: CELEBRATING A SILVER JUBILEE

    Directory of Open Access Journals (Sweden)

    Nino Panagia

    2013-12-01

    Full Text Available The story of the SN 1987A explosion is briefly reviewed. Although this supernova was somewhat peculiar, the study of SN 1987A has clarified quite a number of important aspects of the nature and the properties of supernovae, such as the confirmation of the core collapse of a massive star as the cause of the explosion, as well the confirmation that the decays 56Ni–56Co–56Fe at early times and 44Ti–44Sc at late times, are the main sources of the energy radiated by the ejecta. Still we have not been able to ascertain whether the progenitor was a single star or a binary system, nor have we been able to detect the stellar remnant, a neutron star that should be produced in the core collapse process.

  1. A marketing strategy for a nursing college

    Directory of Open Access Journals (Sweden)

    M. Pryde

    1995-05-01

    Full Text Available The objective of this study is to explore and describe a marketing strategy for a nursing college. An explorative and descriptive research design, within the context of a nursing college and affiliated hospitals, was followed. A literature study of marketing models was undertaken and the Delphi-method was utilised to determine the contribution of marketing staff and the possible content of a marketing strategy for a nursing college. The results were utilised to describe guidelines for such a strategy, consisting of marketers/marketing agents, target market, product, price, promotional activities, place and market research. Recommendations include the planning, implementation and evaluation of strategy, inservice training for potential marketing agents, inclusion of marketing as part of the formal education of tutors and nurse managers,as well as an impact study of the scholar as the main consumer.

  2. A merger shock in A2034

    Energy Technology Data Exchange (ETDEWEB)

    Owers, Matt S.; Couch, Warrick J.; Hopkins, Andrew M. [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Nulsen, Paul E. J.; Ma, Cheng-Jiun; David, Laurence P.; Forman, William R.; Jones, Christine; Van Weeren, Reinout J., E-mail: matthew.owers@aao.gov.au [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2014-01-10

    We present a 250 ks Chandra observation of the cluster merger A2034 with the aim of understanding the nature of a sharp edge previously characterized as a cold front. The new data reveal that the edge is coherent over a larger opening angle and is significantly more bow-shock-shaped than previously thought. Within ∼27° about the axis of symmetry of the edge, the density, temperature, and pressure drop abruptly by factors of 1.83{sub −0.08}{sup +0.09}, 1.85{sub −0.41}{sup +0.41}, and 3.4{sub −0.7}{sup +0.8}, respectively. This is inconsistent with the pressure equilibrium expected of a cold front and we conclude that the edge is a shock front. We measure a Mach number M=1.59{sub −0.07}{sup +0.06} and corresponding shock velocity v {sub shock} ≅ 2057 km s{sup –1}. Using spectra collected at the MMT with the Hectospec multi-object spectrograph, we identify 328 spectroscopically confirmed cluster members. Significantly, we find a local peak in the projected galaxy density associated with a bright cluster galaxy that is located just ahead of the nose of the shock. The data are consistent with a merger viewed within ∼23° of the plane of the sky. The merging subclusters are now moving apart along a north-south axis approximately 0.3 Gyr after a small impact parameter core passage. The gas core of the secondary subcluster, which was driving the shock, appears to have been disrupted by the merger. Without a driving 'piston,' we speculate that the shock is dying. Finally, we propose that the diffuse radio emission near the shock is due to the revival of pre-existing radio plasma that has been overrun by the shock.

  3. Turning a Wild Plant into a Model A Dvu Story

    Directory of Open Access Journals (Sweden)

    Daniel Ioan PACURAR

    2009-06-01

    Full Text Available In the past two decades we have witnessed how a useless wild weed has been transformed from an anonymous into a model plant, probably the most widely cultivated plant species. The process has been rather slowly in the beginning, very laborious on the way, extremely expensive and time consuming, but the outcome is priceless the knowledge that is most likely to frame and fill the blueprint of the first artificial plant, as system biology promises. The plant species is Arabidopsis thaliana and the growers are highly qualified researchers worldwide. This review introduces a new anonymous Brachypodium distachyon that raised big hopes for addressing specific problems of fundamental and practical biology in temperate cereals and forage grasses, and is rapidly becoming a sweetheart for the researchers working with these crops, and not only.

  4. A Project Team: A Team or Just a Group?

    Directory of Open Access Journals (Sweden)

    Katerina Hrazdilova Bockova

    2013-11-01

    Full Text Available This paper deals with issues related to work in either teams or groups. The theoretical part which discusses a team and a group with regards to its definition, classification and basic distinction brings in more on the typology of team roles, personality assessment and sociometric methods. The analytical part tests the project (work team of a medical center represented in terms of personality and motivational types, team roles and interpersonal team relations concerning the willingness of cooperation and communication. The main objective of this work was to determine whether the existing team is not by its nature rather a working group that contributes to the generally perceived stagnation of that field.

  5. Haemorrhage in a scrotal lymphangioma in a child: A rarity

    Directory of Open Access Journals (Sweden)

    Rattan Kamal

    2009-01-01

    Full Text Available We report here a case of cystic lymphangioma of scrotum presenting as acute scrotum due to haemorrhage. The diagnosis was confirmed on ultrasonography and magnetic resonance imaging and managed successfully by surgical excision. There was past history of bilateral congenital cataract for which the patient had undergone surgery with complete visual recovery. Scrotal cystic lymphangioma complicated by haemorrhage is rare; hence, the case is being reported with a review of literature.

  6. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Snowboarding, Skating Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  7. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that ...

  8. Tricolorin A as a Natural Herbicide

    Directory of Open Access Journals (Sweden)

    Blas Lotina-Hennsen

    2013-01-01

    Full Text Available Tricolorin A acts as pre- and post-emergence plant growth inhibitor. In pre-emergence it displays broad-spectrum weed control, inhibiting germination of both monocotyledonous (Lolium mutliflorum and Triticum vulgare and dicotyledonous (Physalis ixocarpa and Trifolium alexandrinum seeds, being the dicotyledonous seeds the most inhibited. Tricolorin A also inhibited seedling growth, and seed respiration, and since the concentrations required for inhibiting both germination and respiration were similar, we suggest that respiration is one of its targets. Tricolorin A at 60 µM acts as a post- emergence plant growth inhibitor by reducing dry plant biomass by 62%, 37%, 33%, and 22% for L. multiflorum, T. alexandrinum, T. vulgare, and P. ixocarpa, respectively, 18 days after its application. In order to determine the potency of tricolorin A as a plant growth inhibitor, paraquat was used as control; the results indicate that tricolorin A acts as a non-selective post-emergence plant growth inhibitor similar to paraquat, since both reduced the biomass production in P. ixocarpa and T. alexandrinum. Therefore, we suggest that tricolorin A will be a good biodegradable herbicide for weeds.

  9. Shaping a Scientific Self

    DEFF Research Database (Denmark)

    Andrade-Molina, Melissa; Valero, Paola

    us to understand how a truth is reproduced, circulating among diverse fields of human knowledge. Also it will show why we accept and reproduce a particular discourse. Finally, we state Euclidean geometry as a truth that circulates in scientific discourse and performs a scientific self. We unfold the...... importance of having students following the path of what schools perceive a real scientist is, no to become a scientist, but to become a logical thinker, a problem solver, a productive citizen who uses reason....

  10. Electrophoresis of a polyelectrolyte through a nanopore

    CERN Document Server

    Ghosal, S

    2006-01-01

    A hydrodynamic model for determining the electrophoretic speed of a polyelectrolyte through a nanopore is presented. It is assumed that the speed is determined by a balance of electrical and viscous forces arising from within the pore and that classical continuum electrostatics and hydrodynamics may be considered applicable. An explicit formula for the translocation speed as a function of the pore geometry and other physical parameters is obtained and is shown to be consistent with experimental measurements on DNA translocation through nanopores in silicon membranes. Experiments also show a weak dependence of the translocation speed on polymer length that is not accounted for by the present model. It is hypothesized that this is due to secondary effects that are neglected here.

  11. When is a bottleneck a bottleneck?

    CERN Document Server

    Schadschneider, Andreas; Popkov, Vladislav

    2015-01-01

    Bottlenecks, i.e. local reductions of capacity, are one of the most relevant scenarios of traffic systems. The asymmetric simple exclusion process (ASEP) with a defect is a minimal model for such a bottleneck scenario. One crucial question is "What is the critical strength of the defect that is required to create global effects, i.e. traffic jams localized at the defect position". Intuitively one would expect that already an arbitrarily small bottleneck strength leads to global effects in the system, e.g. a reduction of the maximal current. Therefore it came as a surprise when, based on computer simulations, it was claimed that the reaction of the system depends in non-continuous way on the defect strength and weak defects do not have a global influence on the system. Here we reconcile intuition and simulations by showing that indeed the critical defect strength is zero. We discuss the implications for the analysis of empirical and numerical data.

  12. Broadcasting a message in a parallel computer

    Energy Technology Data Exchange (ETDEWEB)

    Archer, Charles J; Faraj, Ahmad A

    2013-04-16

    Methods, systems, and products are disclosed for broadcasting a message in a parallel computer that includes: transmitting, by the logical root to all of the nodes directly connected to the logical root, a message; and for each node except the logical root: receiving the message; if that node is the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received; if that node received the message from a parent node and if that node is not a leaf node, then transmitting the message to all of the child nodes; and if that node received the message from a child node and if that node is not the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received and transmitting the message to the parent node.

  13. Hoarding: From a Symptom to a Disorder

    Directory of Open Access Journals (Sweden)

    Suheyla Dogan Bulut

    2015-09-01

    Full Text Available Hoarding is a psychological disorder characterized by excessive collecting, storage and inability to discard large quantities of the objects, usually accompanying a severe level of distress or dysfunctionality. Despite the concept has been known for more than a century, it used to be conceptualized as a component of obsessive compulsive disorder. However, hoarding disorder appears as a distinct psychiatric disorder in the last updated version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5. Accordingly, in this review we aimed to make a general framework in understanding of hoarding disorder which is an attention-grabbing diagnosis in these days. In this regard, we addressed the etiology, clinical features of, and treatment approaches to hoarding disorder. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2015; 7(3.000: 319-332

  14. A Small Deformation of a Simple Theory

    CERN Document Server

    Buican, Matthew

    2016-01-01

    We study an interesting relevant deformation of the simplest interacting N=2 SCFT---the original Argyres-Douglas (AD) theory. We argue that, although this deformation is not strictly speaking Banks-Zaks like (certain operator dimensions change macroscopically), there are senses in which it constitutes a mild deformation of the parent AD theory: the exact change in the "a" anomaly is small and is essentially saturated at one loop. Moreover, contributions from IR operators that have a simple description in the UV theory reproduce a particular limit of the IR index to a remarkably high order. These results lead us to conclude that the IR theory is an N=1 SCFT with the smallest-known "a" and "c" central charges for an interacting SCFT in four dimensions.

  15. Broadcasting a message in a parallel computer

    Energy Technology Data Exchange (ETDEWEB)

    Archer, Charles J; Faraj, Daniel A

    2014-11-18

    Methods, systems, and products are disclosed for broadcasting a message in a parallel computer that includes: transmitting, by the logical root to all of the nodes directly connected to the logical root, a message; and for each node except the logical root: receiving the message; if that node is the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received; if that node received the message from a parent node and if that node is not a leaf node, then transmitting the message to all of the child nodes; and if that node received the message from a child node and if that node is not the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received and transmitting the message to the parent node.

  16. GRB 130427A: a Nearby Ordinary Monster

    CERN Document Server

    Maselli, A; Nava, L; Mundell, C G; Kawai, N; Campana, S; Covino, S; Cummings, J R; Cusumano, G; Evans, P A; Ghirlanda, G; Ghisellini, G; Guidorzi, C; Kobayashi, S; Kuin, P; La Parola, V; Mangano, V; Oates, S; Sakamoto, T; Serino, M; Virgili, F; Zhang, B -B; Barthelmy, S; Beardmore, A; Bernardini, M G; Bersier, D; Burrows, D; Calderone, G; Capalbi, M; Chiang, J; D'Avanzo, P; D'Elia, V; De Pasquale, M; Fugazza, D; Gehrels, N; Gomboc, A; Harrison, R; Hanayama, H; Japelj, J; Kennea, J; Kopac, D; Kouveliotou, C; Kuroda, D; Levan, A; Malesani, D; Marshall, F; Nousek, J; O'Brien, P; Osborne, J P; Pagani, C; Page, K L; Page, M; Perri, M; Pritchard, T; Romano, P; Saito, Y; Sbarufatti, B; Salvaterra, R; Steele, I; Tanvir, N; Vianello, G; Weigand, B; Wiersema, K; Yatsu, Y; Yoshii, T; Tagliaferri, G

    2014-01-01

    Long-duration Gamma-Ray Bursts (GRBs) are an extremely rare outcome of the collapse of massive stars, and are typically found in the distant Universe. Because of its intrinsic luminosity ($L\\sim 3 \\times 10^{53}$ erg s$^{-1}$) and its relative proximity ($z=0.34$), GRB 130427A was a unique event that reached the highest fluence observed in the gamma-ray band. Here we present a comprehensive multiwavelength view of GRB 130427A with Swift, the 2-m Liverpool and Faulkes telescopes and by other ground-based facilities, highlighting the evolution of the burst emission from the prompt to the afterglow phase. The properties of GRB 130427A are similar to those of the most luminous, high-redshift GRBs, suggesting that a common central engine is responsible for producing GRBs in both the contemporary and the early Universe and over the full range of GRB isotropic energies.

  17. A Guarda durante a II Guerra Mundial

    OpenAIRE

    Tadeu, Tiago Agostinho Arrifano

    2011-01-01

    O trabalho que aqui se apresenta foca a economia de guerra portuguesa durante a Segunda Guerra Mundial, mais concretamente no distrito da Guarda. A análise de uma zona específica do país permitirá fazer a comparação com os estudos já realizados para a realidade nacional do país. A delimitação geográfica escolhida também ganha uma acrescida importância tendo em conta que se trata de uma área de fronteira, onde havia intensos contactos com Espanha, fruto de fenómenos típicos de guerra como o co...

  18. Scattering of a Baseball by a Bat

    CERN Document Server

    Cross, R; Cross, Rod; Nathan, Alan M.

    2006-01-01

    A ball can be hit faster if it is projected without spin but it can be hit farther if it is projected with backspin. Measurements are presented in this paper of the tradeoff between speed and spin for a baseball impacting a baseball bat. The results are inconsistent with a collision model in which the ball rolls off the bat and instead imply tangential compliance in the ball, the bat, or both. If the results are extrapolated to the higher speeds that are typical of the game of baseball, they suggest that a curveball can be hit with greater backspin than a fastball, but by an amount that is less than would be the case in the absence of tangential compliance.

  19. A numerical simulation of a contrail

    Energy Technology Data Exchange (ETDEWEB)

    Levkov, L.; Boin, M.; Meinert, D. [GKSS-Forschungszentrum Geesthacht GmbH, Geesthacht (Germany)

    1997-12-31

    The formation of a contrail from an aircraft flying near the tropopause is simulated using a three-dimensional mesoscale atmospheric model including a very complex scheme of parameterized cloud microphysical processes. The model predicted ice concentrations are in very good agreement with data measured during the International Cirrus Experiment (ICE), 1989. Sensitivity simulations were run to determine humidity forcing on the life time of contrails. (author) 4 refs.

  20. Telecom 2-A (TC2A)

    Science.gov (United States)

    Dulac, J.; Latour, J.

    1991-01-01

    The DSN (Deep Space Network) mission support requirements for Telecom 2-A (TC2A) are summarized. The Telecom 2-A will provide high-speed data link applications, telephone, and television service between France and overseas territories. The mission objectives are outlined and the DSN support requirements are defined through the presentation of tables and narratives describing the spacecraft flight profile; DSN support coverage; frequency assignments; support parameters for telemetry, command and support systems; and tracking support responsibility.

  1. A Hemangiosarcoma Case in a Dog

    OpenAIRE

    KARABAĞLI, Gamze; DÜZGÜN, Oktay; YILDAR, Esma; ERDOĞAN, Özge; GÜREL, Aydın

    2011-01-01

    The material of this study is a 3.5 years old male Rottweiler dog presented to Istanbul University Veterinary Faculty Surgery Clinics with a complaint of swelling in the right shoulder region. A diagnosis of hematoma was made and treatment was performed, but swelling started to grow gradually and general well-being deteriorated. When the drain was controlled, drainage of fluid containing blood was observed. Anemia and leucocytosis was determined on examination of the blood. The patient was op...

  2. A silicon diode dosimeter with a memory

    International Nuclear Information System (INIS)

    An integrating dosimeter using a silicon diode has been developed which can be used to check the calibration of radiation therapy treatment units at remote facilities by mail. The dose reading is retained indefinitely in a battery-operated CMOS digital counter. The accuracy of the device is at least +-0.6% standard deviation, as determined by 60Co irradiations over a two month period. (orig.)

  3. Dialog between a Lexicographer and a Translator

    OpenAIRE

    Mark Kit; Violetta Koseska-Toszewa

    2015-01-01

    Dialog between a Lexicographer and a TranslatorThe discussion between the authors of the paper concerns the most pressing issues encountered in natural language semantics, as well as in corpus linguistics and computational linguistics. A broad range of knowledge, allowing linguists and information scientists to work together, is required in these areas. The paper describes some primary problems of human and machine translation caused by gaps between different fields of knowledge. The authors ...

  4. A Brain Gain with a Brain Drain

    OpenAIRE

    Stark, Oded; Prskawetz, Alexia; Helmenstein, Christian

    1997-01-01

    Abstract: We study human capital depletion and formation in an economy open to out-migration, as opposed to an economy which is closed. Under the natural assumption of asymmetric information, the enlarged opportunities and the associated different structure of incentives can give rise to a brain gain in conjunction with a brain drain. Migration by high-skill members of its workforce notwithstanding, the home country can end up with a higher average level of human capital per worker.;

  5. [A gun silencer of a special kind].

    Science.gov (United States)

    Schyma, C; Schyma, P; Milbradt, H

    2000-01-01

    The authors report about a small bore pistol with silencer. In addition, the silencer can be sealed up by a rubber plate. This leads to a false estimation of the shooting distance. Also at close range shots the shot with the silencer and the rubber seal leaves hardly gunshot residues. The bullet wipe persists but microradiography shows his changed morphological composition. The use of the rubber seal leads predominantly to atypical bullet holes. PMID:10829239

  6. Shame : a pastoral study / Craig A. Brannan

    OpenAIRE

    Brannan, Craig Alexander

    2005-01-01

    Shame may be considered one of the most painful emotions that an individual must endure. Recent research within the scientific discipline of theology has identified the fact that there has been little theological study on shame from a basis-theoretical perspective. This has resulted in a deficiency of theological-practical interventions to assist pastoral counsellors and believers in addressing shame from a Biblical-integrative perspective. Although many of the scientific disci...

  7. A tandem repeat gene in a picornavirus.

    OpenAIRE

    Forss, S; Schaller, H

    1982-01-01

    Three closely related genes for the small genome-linked protein (VPg) of picornaviruses have been identified by sequence analysis as a tandem repeat in the genome of Foot and Mouth Disease Virus (FMDV), strain O1K. This unusual structure was also found in the genome of strain C1O, belonging to a different FMDV serotype. Predicted biochemical properties of the three VPg gene products are in excellent agreement with the data from protein analysis of a heterogeneous VPg population from a third F...

  8. A pipette dispenses a charged droplet

    Science.gov (United States)

    Choi, Dongwhi; Lee, Horim; Im, Do Jin; Kang, In Seok; Kang, Kwan Hyoung

    2012-11-01

    Micropipettes are widely used in many scientific and engineering fields. However, it is hardly known that a droplet dispensed from a plastic pipette tip has a considerable amount of charges (order of 10-10 C). Here we report that the charged droplet is dispensed from a commercial and disposable plastic pipette tip and this charge is originated from the natural electrification between a solution and the inner surface of the pipette tip. The charge amount is dependent on not only the physicochemical properties of a solution (e.g., pH and a concentration) but also dispensing environments (e.g., atmospheric humidity and type of commercial pipette tip). To investigate the effects of the charge on the droplet dispensing, we calculate the electrical force between the droplet and the pipette tip though numerical simulation. The micropipette users especially, who are dealing with discrete droplets in their experiments, should consider this charge effect in their dispensing of a droplet. This work was supported by the National Research Foundation of Korea (NRF) Grant No. R0A-2007-000-20098-0 funded by the Korea government (MEST) and No. 20090083510 through Multiphenomena CFD Engineering Research Center.

  9. A City Is a Complex Network

    CERN Document Server

    Jiang, Bin

    2015-01-01

    A city is not a tree but a semi-lattice. To use a more fashionable term, a city is a complex network. The complex network constitutes a unique topological perspective on cities and enables us to better understand the kind of problem a city is. The topological perspective differentiates it from the perspectives of Euclidean geometry and Gaussian statistics that deal with essentially regular shapes and more or less similar things. Many urban theories, such as the Central Place Theory, Zipf's Law, the Image of the City, and the Theory of Centers can be interpreted from the point of view of complex networks. A livable city consists of far more small things than large ones, and their shapes tend to be irregular and rough. This chapter illustrates the complex network view and argues that we must abandon the kind of thinking guided by Euclidean geometry and Gaussian statistics, and instead adopt fractal geometry, power-law statistics, and Alexander's living geometry to develop sustainable cities. Keywords: Scaling, ...

  10. Converting a Display Screen into a Touchscreen

    Institute of Scientific and Technical Information of China (English)

    Qun Wang; Jun Cheng; San-Ming Shen; Yi-Jiang Shen; Jian-Xin Pang

    2014-01-01

    A method is presented to convert any display screen into a touchscreen by using a pair of cameras. Most state of art touchscreens make use of special touch-sensitive hardware or depend on infrared sensors in various configurations. We describe a novel computer-vision-based method that can robustly identify fingertips and detect touch with a precision of a few millimeters above the screen. In our system, the two cameras capture the display screen image simultaneously. Users can interact with a computer by the fingertip on the display screen. We have two important contributions:first, we develop a simple and robust hand detection method based on predicted images. Second, we determine whether a physical touch takes places by the homography of the two cameras. In this system, the appearance of the display screen in camera images is inherently predictable from the computer output images. Therefore, we can compute the predicted images and extract human hand precisely by simply subtracting the predicted images from captured images.

  11. A second supernova inside Puppis A?

    International Nuclear Information System (INIS)

    Here we present narrow-band images of an unusual swirl structure located near the centre of the Puppis A supernova remnant, which reveal three overlapping filamentary systems of highly diverse composition. One is dominated by emission lines of nitrogen, one by oxygen and one by sulphur. Spectra indicate that these small rings have high velocities and a corresponding kinematic age of less than 800 yr. The youth and unusual chemistry lead us to suggest that a second supernova has exploded within the shell of Puppis A, giving rise to the swirl structure. (author)

  12. Simulating a Guitar with a Conventional Sonometer

    Science.gov (United States)

    Burstein, Zily; Gower, Christina M.; Varieschi, Gabriele U.

    Musical acoustics is an interesting sub-field of physics which is usually able to engage students in a dual perspective, by combining science and art together. The physics principles involved in most musical instruments can be easily demonstrated with standard laboratory equipment and can become part of lecture or lab activities. In particular, we will show in this paper how to simulate a guitar using a conventional sonometer, in relation to the problem of the instrument intonation, i.e., how to obtain correctly tuned notes on a guitar or similar string instruments.

  13. Simulating a guitar with a conventional sonometer

    CERN Document Server

    Burstein, Zily; Varieschi, Gabriele U

    2011-01-01

    Musical acoustics is an interesting sub-field of physics which is usually able to engage students in a dual perspective, by combining science and art together. The physics principles involved in most musical instruments can be easily demonstrated with standard laboratory equipment and can become part of lecture or lab activities. In particular, we will show in this paper how to simulate a guitar using a conventional sonometer, in relation to the problem of the instrument intonation, i.e., how to obtain correctly tuned notes on a guitar or similar string instruments.

  14. A forgotten clinical sign making a comeback.

    Science.gov (United States)

    Chiam, K H; A Hing, C T; Low, L L

    2014-02-01

    We report a case of Staphylococcus aureus infective endocarditis in a patient presenting with fever and rare cutaneous manifestations of Osler Nodes and Janeway Lesions. There had not been any distinct risk factors. His echocardiography subsequently revealed vegetation at the anterior mitral valve leaflet. As Staphylococcus aureus infective endocarditis is of utmost significance in morbidity and mortality, a sharp clinical acumen and follow up investigations is required alongside a prolonged course of antibiotics. Our patient was then started on intravenous cloxacillin for 28 days and gentamicin for 5 days to which he made good progress and recovery. PMID:24814630

  15. Playing a quantum game with a qutrit

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Urbasi [Institute for Quantum Computing, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L3G1 and Raman Research Institute, Sadashivanagar, Bangalore 560080 (India); Kolenderski, Piotr [Institute for Quantum Computing, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L3G1 and Institute of Physics, Copernicus University, Grudziqdzka 5, 87-100 Torun (Poland); Youning, Li [Department of Physics, Tsinghua University, Beijing 100084, P.R. (China); Zhao, Tong; Volpini, Matthew; Laflamme, Raymond; Jennewein, Thomas [Institute for Quantum Computing, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L3G1 (Canada); Cabello, Adan [Departmento de Fisica Aplicada II, Universidad de Sevilla, E-41012, Sevilla, Spain and Department of Physics, Stockholm University, S-10691 Stockholm (Sweden)

    2014-12-04

    The Aharon Vaidman (AV) quantum game [1] demonstrates the advantage of using simple quantum systems to outperform classical strategies. We present an experimental test of this quantum advantage by using a three-state quantum system (qutrit) encoded in a spatial mode of a single photon passing through a system of three slits [2,3]. We prepare its states by controlling the photon propagation and the number of open and closed slits. We perform POVM measurements by placing detectors in the positions corresponding to near and far field. These tools allow us to perform tomographic reconstructions of qutrit states and play the AV game with compelling evidence of the quantum advantage.

  16. A conversation with Marvin A. Schneiderman

    OpenAIRE

    Simon, Richard M.

    1997-01-01

    Marvin A. Schneiderman was born on December 25, 1918, in Brooklyn, New York. He received a B.S. degree in mathematics and statistics from the City College of New York in 1939, an M.S. degree in statistics from American University in 1953 and a Ph.D. in statistics from American University in 1961. Additional graduate training and research was done at Ohio State University, Harvard Graduate School of Business and the London School of Hygiene and Tropical Medicine. He is a Fell...

  17. A Proposal for a Mindset of a Project Manager

    DEFF Research Database (Denmark)

    Eriksson, Joakim; Hansen, Claus Thorp

    2008-01-01

    A company’s product strategy and its management of the product development process have been found to be key factors for a product’s success on the market [1]. Project managers of development projects need support to make process decisions and defining goals that are consistent with the business...... product development projects it is desirable to reduce the level of uncertainty in order to make decisions without having to redo them later in the project resulting in longer lead time and higher costs. It is the project manager’s responsibility to manage this uncertainty in a complex ever...... clarification of decision situations and consequences is rarely used in practice and structured reasoning about project and product performance when making decisions is also rare. In order to enhance the project managers’ understanding of decision-making in product development projects, the objective of this...

  18. Towards a personalized Internet: a case for a full decentralization.

    Science.gov (United States)

    Kermarrec, Anne-Marie

    2013-03-28

    The Web has become a user-centric platform where users post, share, annotate, comment and forward content be it text, videos, pictures, URLs, etc. This social dimension creates tremendous new opportunities for information exchange over the Internet, as exemplified by the surprising and exponential growth of social networks and collaborative platforms. Yet, niche content is sometimes difficult to retrieve using traditional search engines because they target the mass rather than the individual. Likewise, relieving users from useless notification is tricky in a world where there is so much information and so little of interest for each and every one of us. We argue that ultra-specific content could be retrieved and disseminated should search and notification be personalized to fit this new setting. We also argue that users' interests should be implicitly captured by the system rather than relying on explicit classifications simply because the world is by nature unstructured, dynamic and users do not want to be hampered in their actions by a tight and static framework. In this paper, we review some existing personalization approaches, most of which are centralized. We then advocate the need for fully decentralized systems because personalization raises two main issues. Firstly, personalization requires information to be stored and maintained at a user granularity which can significantly hurt the scalability of a centralized solution. Secondly, at a time when the 'big brother is watching you' attitude is prominent, users may be more and more reluctant to give away their personal data to the few large companies that can afford such personalization. We start by showing how to achieve personalization in decentralized systems and conclude with the research agenda ahead. PMID:23419849

  19. What Is a Colonoscopy

    Medline Plus

    Full Text Available ... a gastroenterologist for the last 25 years. And, we are about to do a colonoscopy, which is ... that will prevent colon cancer from forming. So, we have become a standard. We are in a ...

  20. Create a Logo.

    Science.gov (United States)

    Duchen, Gail

    2002-01-01

    Presents an art lesson that introduced students to graphic art as a career path. Explains that the students met a graphic artist and created a logo for a pretend client. Explains that the students researched logos. (CMK)

  1. A Journey from a Corruption Port to a Tax Haven

    OpenAIRE

    Hebous, Shafik; Lipatov, Vilen

    2012-01-01

    We sketch a model according to which tax havens attract corporate income generated in corrupted countries. We consider the choice of optimal bribes by corrupt o¢ cials and the share of the proceeds of corruption that will be concealed in tax havens. In our framework, tax havens have two opposite e¤ects on welfare. First, tax havens?services have a positive e¤ect on welfare through encouraging investment by ?rms fearing expropriation and bribes in corrupt countries. Second, by supporting corru...

  2. Vampire as a metaphor

    OpenAIRE

    Jovanović Bojan G.

    2004-01-01

    A vampire, as a demonized deceased human, is used as a specific metaphor to explain unknown sources of various troubles in a community. A malicious deceased one is a mythical creature and as such is to blame for the existing troubles in a community; the creature, in turn, becomes a subject i.e., a victim in a ritual performed to avert the difficulties, so that the community in question could return to its daily life. A myth revival establishes diagnosis and appropriate therapy for the crisis ...

  3. Impact of a postcard versus a questionnaire as a first reminder in a postal lifestyle survey.

    OpenAIRE

    Roberts, H; Pearson, J C; DENGLER, R.

    1993-01-01

    STUDY OBJECTIVE--The study aimed to consider the impact of two different types of reminder on response rates and costs in a postal survey. DESIGN--The study was a cross sectional survey. A self-completion lifestyle questionnaire was used. Those who did not respond after the initial mailing were randomly allocated to receive either a postcard or questionnaire as a first reminder. All outstanding non-responders received a questionnaire as a second reminder. SUBJECTS--A representative sample of ...

  4. Motion of a Pendulum

    Directory of Open Access Journals (Sweden)

    Jared Wynn

    2010-01-01

    Full Text Available The objective of this project is to derive and solve the equation of motion for a pendulum swinging at small angles in one dimension. The pendulum may be either a simple pendulum like a ball hanging from a string or a physical pendulum like a pendulum on a clock. For simplicity, we only considered small rotational angles so that the equation of motion becomes a harmonic oscillator.

  5. A case of ectrodactyly in a neonate.

    Science.gov (United States)

    Kalathia, Mitul B; Seta, Avani A; Parmar, Parin N

    2013-07-01

    Ectrodactyly also known as Split hand/foot malformation is a rare limb malformation with autosomal dominant in heritance with variable penetrance, commonly known as "lobster claw hand". Usually it involves midline clefts of the hands and feet with syndactyly. We report a neonate with ectrodactyly and brief review of literature of condition. PMID:24251264

  6. A Case of Ectrodactyly in a Neonate

    OpenAIRE

    Kalathia, Mitul B.; Seta, Avani A.; Parmar, Parin N.

    2013-01-01

    Ectrodactyly also known as Split hand/foot malformation is a rare limb malformation with autosomal dominant in heritance with variable penetrance, commonly known as "lobster claw hand". Usually it involves midline clefts of the hands and feet with syndactyly. We report a neonate with ectrodactyly and brief review of literature of condition.

  7. A VORTEX MODEL OF A HELICOPTER ROTOR

    Directory of Open Access Journals (Sweden)

    Valentin BUTOESCU

    2009-06-01

    Full Text Available A vortex model of a helicopter rotor is presented. Each blade of the rotor has three degrees of freedom: flapping, lagging and feathering. The motions after each degree of freedom are also known for all blades. The blade is modelled as a thin vortex surface. The wakes are free fluid surfaces. A system of five equations are obtained: the first one is the integral equation of the lifting surface (rotor, the next three describe the wakes motion, and the last one relates the vortex strength on the wakes and the variation of vorticity on the rotor. A numerical solution of this system is presented. To avoid the singularities that can occur due to the complexity of vortex system, a desingularized model of the vortex core was adopted. A Mathcad worksheet containing the method has been written.The original contribution of the work. The calculation method of the motion of the wakes free vortex system, the development of the vortex cores in time and a new method to approximate the aerodynamic influence of remoted wake regions.

  8. A toolkit for a generative lexicon

    CERN Document Server

    Henry, Patrick

    2008-01-01

    In this paper we describe the conception of a software toolkit designed for the construction, maintenance and collaborative use of a Generative Lexicon. In order to ease its portability and spreading use, this tool was built with free and open source products. We eventually tested the toolkit and showed it filters the adequate form of anaphoric reference to the modifier in endocentric compounds.

  9. A farmer becomes a social pedagogue

    DEFF Research Database (Denmark)

    Mellon, Karsten

    2016-01-01

    Summary: In Denmark various non-traditional students are mature-age students who already have some kind of a vocational background. When applying to do a professional degree, most of them fall outside the traditional admission requirements, which is why individual assessment of applicants is nece...

  10. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... dental words mean. The Life of a Tooth games Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | Reprints and Permissions | Privacy Statement | Terms and Conditions © 1996-2016 Academy of General Dentistry. All Rights Reserved.

  11. A step up for a few postdocs

    CERN Multimedia

    2000-01-01

    Dutch postdocs at the Netherlands Cancer Institute complained recently of their lack of research independance and poor career progress. As a result they are now getting a proper career structure. Other institutions should also tackle this problem before serious recruitment problems develop (1/2 p).

  12. A Miracle over A Decadef Wuxi Sunmart

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ Miracle started A decade ago, Wuxi Sunmart was just no name.At that time, few people noticed Jiangsu Snow Leopard Atomi-zation Pot Industry Limited Company, which was established in early 1998, as it was a small workshop with the registered capital of only RMB 1.6 million.And that is where Wuxi Sunmart's miracle began.

  13. Ciencia: Nivel A (Science: Level A).

    Science.gov (United States)

    Duron, Dolores; And Others

    A teacher's manual was developed for an elementary level science course in Spanish as part of an immersion program for English speaking children. The Level A manual is designed for kindergarten and grade 1 pupils. The five units cover the basic concepts of the weather, colors, animals, plants, and the five senses. Each unit includes vocabulary,…

  14. Build a School, Inspire a Community

    Science.gov (United States)

    Bowen-Eggebraaten, Mary; Hoffman, Paul J.

    2010-01-01

    When River Crest Elementary School opened on September 2, 2008, it was clear that the effect of a "green" school would extend beyond the students who walked through the doors for class each day. The 93,450-square-foot facility in Hudson, Wisconsin, serves as a catalyst for sustainable change and has been an educational tool for ecofriendly…

  15. A Small Essay About a Big Boulevard

    Directory of Open Access Journals (Sweden)

    Elena Grigoryeva

    2015-08-01

    Full Text Available The essay presents the analogies of turning city borders and walls into boulevards and gardens through the examples of Moscow and Irkutsk. The main street of Irkutsk is viewed in a new light, as a boulevard. It is proposed to take into consideration the peculiarities of the four sense-parts of the street when working on design codes.

  16. A child with pica. A case presentation.

    Directory of Open Access Journals (Sweden)

    Lidia Rosa Pérez González

    2005-04-01

    Full Text Available This is a case of a 4 year old child who was brought to the provincial Pediatric Hospital because of faecal stones. Iron deficit and intestinal parasites were found . The patient received treatment for 6 months till the ingestion of stones disappeared with the control of the etiologic factors that caused it.

  17. Radioactivity a history of a mysterious science

    CERN Document Server

    Malley, Marjorie C

    2011-01-01

    Beginning with an obscure discovery in 1896, radioactivity led researchers on a quest for understanding that ultimately confronted the intersection of knowledge and mystery. This book tells the story of a new science that profoundly changed physics and chemistry, as well as areas such as medicine, geology, meteorology, archaeology, industry, politics, and popular culture.

  18. Matematicas: Nivel A (Mathematics: Level A).

    Science.gov (United States)

    Duron, Dolores; And Others

    A teacher's manual was developed for an elementary level mathematics course in Spanish as part of an immersion program for English speaking children. The Level A manual is designed for kindergarten and grade 1 pupils. Teaching procedures, conceptual objectives, vocabulary, and structures are included. Activities are designed to teach either…

  19. [A strong man with a weak shoulder].

    Science.gov (United States)

    Henket, Marjolijn; Lycklama á Nijeholt, Geert J; van der Zwaal, Peer

    2013-01-01

    A 47-year-old former olympic athlete had pain and weakness of his left shoulder. There was no prior trauma. He had full range-of-motion and a scapular dyskinesia. There was atrophy of the trapezius and sternocleidomastoideus muscles. He was diagnosed with 'idiopathic neuritis of the accessorius nerve'. PMID:24326139

  20. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health Why is Oral Health Important for Men? Men: Looking for a Better ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  1. Building a Digital Library on a Shoestring

    Science.gov (United States)

    Boyd, Kate Foster; Creighton, Alma

    2006-01-01

    In this article, the authors discuss ways one can create a digital library on a shoestring despite the current high technology costs. Here, they describe the University of South Carolina's digital library development. The cost associated with building and maintaining the digital collections seems to have been worth it based on the feedback that…

  2. A Proposal for a Civics Study Program

    Science.gov (United States)

    Marcus, Stuart Paul; Richman, Paul Jeffrey

    1978-01-01

    Two high school students recommend a civics study program which would include (1) a required course on governmental structure, responsibilities, and the U.S. Constitution, and (2) elective courses on crime, juvenile delinquency, state and local government, and history of constitutional law. (AV)

  3. Urihi A: A Terra-Floresta Yanomami

    OpenAIRE

    Welch, James R.

    2010-01-01

    Review of Urihi A: A Terra-Floresta Yanomami. Bruce Albert and William Milliken with Gale Goodwin Gomez. São Paulo: Instituto Socioambiental, 2009. 207 pp., illustrations, tables, bibliography, appendices, index. Paperback ISBN: 978‐85 85994‐72‐3.

  4. Just a routine operation: a critical discussion.

    Science.gov (United States)

    McClelland, G; Smith, M B

    2016-05-01

    This article has summarised a critical discussion of the human factors that contributed to the death of a patient from a failure to respond appropriately to a 'can't intubate, can't ventilate' scenario. The contributory factors included the clinical team's inability to communicate, prioritise tasks and demonstrate effective leadership and assertive followership. The film Just a routine operation has now been in circulation for several years. When a system is designed and introduced with the intention of making a change to clinical practice, it can quickly become just another component of an organisation's architecture and complacency around its use can develop. This article has been written specifically for perioperative practitioners to renew the debate around the human factors that contribute to patient harm. By critically discussing Just a routine operation and attempting to review why the incident occurred, this article has attempted to emphasise that some of the conditions and behaviours that contributed to the death of Elaine Bromiley may be latent within our organisations and teams, and may continue to contribute to failures that affect patient safety. PMID:27400489

  5. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health Men: Looking for a Better Job? Start by ... a Composite Resin (White Filling)? Why is Oral Health Important for Men? How Do I Care for ...

  6. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health When Should My Child First See a Dentist? ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  7. Locating a circle on a sphere

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2007-01-01

    We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of distances between the circle and the facilities is minimized or such that the maximum distance is minimized. The problem properties are analyzed, and we give solution...... contexts such as search-and-rescue missions and medical or biological studies....

  8. How Could a Beaver Start a War?

    Science.gov (United States)

    Millward, Robert

    2010-01-01

    Students gain a better understanding of war and economics when the variables come alive through stories, artifacts, and paintings. In this article, the author describes a short story about the fur trade which can generate lots of student questions about the fur economics, the Eastern Woodland Indians, trade artifacts, and war. The author also…

  9. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Quick Reference Learn more Nutrition - Adults What is Dental Amalgam (Silver Filling)? Are You Biting Off More Than You Can Chew? What is Baby Bottle Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist Is My Child at Risk for Early Childhood ... The Life of a Tooth games ...

  10. Life of a Tooth: A Visual Timeline

    Science.gov (United States)

    ... Quick Reference Learn more Nutrition - Adults What is Dental Amalgam (Silver Filling)? Are You Biting Off More Than You Can Chew? What is Baby Bottle Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist Is My Child at Risk for Early Childhood ... The Life of a Tooth games ...

  11. Danish - a Language with a Future?

    DEFF Research Database (Denmark)

    Petersen, Margrethe; Shaw, Philip

    1999-01-01

    A project on the use of English for academic purposes in Denmark has revealed that the academic article written in Danish may be a dying genre. Based on this finding and on observations on the use of English in Danish texts (or contexts), the future of the Danish language and of translation and...

  12. A Report on A Christmas Carol

    Institute of Scientific and Technical Information of China (English)

    周志聪

    2010-01-01

    @@ Charles Dickens is generally considered the greatest English novelist of the Victorian period,as well as a vigorous social campaigner.His works are characterized by attacks on social evils,injustice and hypocrisy,and among which there is one that Dickens called his "little Christmas Book",that is A Christmas Carol.

  13. A Reverse Shock in GRB 160509A

    CERN Document Server

    Laskar, Tanmoy; Berger, Edo; Fong, Wen-fai; Margutti, Raffaella; Shivvers, Isaac; Williams, Peter K G; Kopac, Drejc; Kobayashi, Shiho; Mundell, Carole; Gomboc, Andreja; Zheng, WeiKang; Menten, Karl M; Graham, Melissa L; Filippenko, Alexei V

    2016-01-01

    We present the second multi-frequency radio detection of a reverse shock in a $\\gamma$-ray burst. By combining our extensive radio observations of the Fermi-LAT GRB 160509A at $z = 1.17$ up to $20$ days after the burst with Swift X-ray observations and ground-based optical and near-infrared data, we show that the afterglow emission comprises distinct reverse shock and forward shock contributions: the reverse shock emission dominates in the radio band at $\\lesssim10~$days, while the forward shock emission dominates in the X-ray, optical, and near-infrared bands. Through multi-wavelength modeling, we determine a circumburst density of $n_0\\approx10^{-3}~$cm$^{-3}$, supporting our previous suggestion that a low-density circumburst environment is conducive to the production of long-lasting reverse shock radiation in the radio band. We infer the presence of a large excess X-ray absorption column, $N_{\\rm H} \\approx 1.5\\times10^{22}~$cm$^{-2}$, and a high rest-frame optical extinction, $A_{\\rm V}\\approx3.4~$mag. We...

  14. A Monopole Near a Black Hole

    CERN Document Server

    Bunster, C; Bunster, Claudio; Henneaux, Marc

    2007-01-01

    We study an electric charge held at rest outside a magnetically charged black hole. We find that even if the electric charge is treated as a perturbation on a spherically symmetric magnetic Reissner-Nordstrom hole, the geometry at large distances is that of a magnetic Kerr-Newman black hole. When the charge approaches the horizon and crosses it, the exterior geometry becomes that of a Kerr-Newman hole with electric and magnetic charges and with total angular momentum given by the standard value for a charged monopole pair. Thus, in accordance with the "no-hair theorem", once the charge is captured by the black hole, the angular momentum associated with the charge monopole system, looses all traces of its exotic origin and it is perceived from the outside as common rotation. It is argued that a similar analysis performed on Taub-NUT space should give the same result, namely, if one holds an ordinary mass outside of the horizon of a Taub-NUT space with only magnetic mass, the system, as seen from large distance...

  15. A false explosion for a real intervention

    CERN Multimedia

    2006-01-01

    Together with their French and Swiss counterparts, the CERN Fire Brigade carried out a spectacular exercise in the LHCb cavern. It was designed to test the coordination of the fire and rescue services of the Organization's two Host States. Inside a temporary medical station set up above ground, the emergency teams deliver medical care to the injured before they are taken to hospital.An accident victim in the underground cavern about to be evacuated. 'I was taking a group of visitors on a tour of the LHCb cavern when there was a huge explosion and I suffered serious burns to the thorax. The rescue services arrived on the scene and I was taken to the medical station'. Fortunately, this is not an account of real events but a scenario given to one of 20 volunteer 'victims' who took part in a large-scale safety exercise in the LHCb cavern. On 26 September, the CERN Fire Brigade organised a spectacular exercise in collaboration with the CERN Medical Service, the Fire and Rescue Service (SDIS) of the Department of t...

  16. Keeping a Marine Aquarium - A Manual.

    Science.gov (United States)

    Valenti, Christopher

    Presented is advice on how to set up and maintain a saltwater aquarium, and a discussion on everything from algae growth to constructing an underground filter to hatch brine shrimp. Information on which tropical and temperate animals are appropriate for marine aquaria and how to collect them is also included. (Author/SB)

  17. A smectic A polymorphism at low temperature

    OpenAIRE

    Sigaud, G.; Achard, M. F.; Hardouin, F.; Gasparoux, H.

    1985-01-01

    Evidence is given for the first time at low temperature of an example of a polymorphism of smectic A phases, in mixtures of cyanocyclohexylcyclohexane with aminopyrene. We briefly discuss the conditions required to stabilize bilayered fluid smectics in such new cyano-amino associated systems.

  18. Marketing Education on a Shoestring: A Model.

    Science.gov (United States)

    Shreeve, William; And Others

    Few educators envision themselves as marketing or public relations experts, yet economic reality is forcing many academicians into these roles. Over the past four years, the Eastern Washington University Department of Education has developed a successful marketing model for educators. The model begins with a successful reform of department…

  19. A phylogenetic blueprint for a modern whale.

    Science.gov (United States)

    Gatesy, John; Geisler, Jonathan H; Chang, Joseph; Buell, Carl; Berta, Annalisa; Meredith, Robert W; Springer, Mark S; McGowen, Michael R

    2013-02-01

    The emergence of Cetacea in the Paleogene represents one of the most profound macroevolutionary transitions within Mammalia. The move from a terrestrial habitat to a committed aquatic lifestyle engendered wholesale changes in anatomy, physiology, and behavior. The results of this remarkable transformation are extant whales that include the largest, biggest brained, fastest swimming, loudest, deepest diving mammals, some of which can detect prey with a sophisticated echolocation system (Odontoceti - toothed whales), and others that batch feed using racks of baleen (Mysticeti - baleen whales). A broad-scale reconstruction of the evolutionary remodeling that culminated in extant cetaceans has not yet been based on integration of genomic and paleontological information. Here, we first place Cetacea relative to extant mammalian diversity, and assess the distribution of support among molecular datasets for relationships within Artiodactyla (even-toed ungulates, including Cetacea). We then merge trees derived from three large concatenations of molecular and fossil data to yield a composite hypothesis that encompasses many critical events in the evolutionary history of Cetacea. By combining diverse evidence, we infer a phylogenetic blueprint that outlines the stepwise evolutionary development of modern whales. This hypothesis represents a starting point for more detailed, comprehensive phylogenetic reconstructions in the future, and also highlights the synergistic interaction between modern (genomic) and traditional (morphological+paleontological) approaches that ultimately must be exploited to provide a rich understanding of evolutionary history across the entire tree of Life. PMID:23103570

  20. A multiplicity trigger for a Cherenkov detector

    International Nuclear Information System (INIS)

    The Multiplicity Trigger (MT) is a device for deciding if, in a given time window, the number of wires that are hit in a multi wire proportional chamber (MWPC) is within given limits. The MT is designed for a Cherenkov detector, using a MWPC with 155 sense wires. It has ten inputs with sixteen channels on each, for 160 ECL input signals from the MWPC. With the MT, it is possible to decide if the number of hits is greater than n out of 160, where n is called the multiplicity. Here, 2 < n < 30, with an accuracy of +- 1. The time window can be adjusted from 0.7 to 4 μs. The MT has four separate NIM outputs, to make it possible to have four different values of n at the same time. The propagation delay from input to output is at the most 100 ns. (author)

  1. A fat Higgs with a magnetic personality

    Science.gov (United States)

    Craig, Nathaniel; Stolarski, Daniel; Thaler, Jesse

    2011-11-01

    We introduce a novel composite Higgs theory based on confining supersymmetric QCD. Supersymmetric duality plays a key role in this construction, with a "fat" Higgs boson emerging as a dual magnetic degree of freedom charged under the dual magnetic gauge group. Due to spontaneous color-flavor locking in the infrared, the electroweak gauge symmetry is aligned with the dual magnetic gauge group, allowing large Yukawa couplings between elementary matter fields and the composite Higgs. At the same time, this theory exhibits metastable supersymmetry breaking, leading to low-scale gauge mediation via composite messengers. The Higgs boson is heavier than in minimal supersymmetric theories, due to a large F -term quartic coupling as well as small non-decoupling D-terms. This theory predicts quasi-stable TeV-scale pseudo-modulini, some of which are charged under standard model color, possibly giving rise to long-lived R-hadrons at the LHC.

  2. A new approach to a unified force

    International Nuclear Information System (INIS)

    The assumption is presented that the true structure of the world is a six dimensional (6D) Euclidian space in which our 4D world is embedded properly. Because of the local isomorphism of SO(6) and SU(4) physics developed for this space crystallizes as being very symmetric with only one force and no gravity. Analyzing how this 6D physics can be interpreted by a 4D observer it emerges that the transition seems to be something like a universal remedy. It shows that the result allows formulating our known physics. It gives reason why quantum physics is a probabilistic theory, can explain quarks as transformed 6D symmetry, can deduct our three forces from the one 6D force, can introduce particle mass in the Lagrange density and can implement gravity. The paper presents a structural description. To achieve quantitative results mathematical problems have to be overcome.

  3. A broken heart in a broken car.

    Science.gov (United States)

    Schlossbauer, Susanne Anna; Ghadri, Jelena-Rima; Cammann, Victoria Lucia; Maier, Willibald; Lüscher, Thomas F; Templin, Christian

    2016-01-01

    Takotsubo syndrome (TTS) is still a relatively understudied and often undetected disease. It is usually preceded by emotional or physical triggers. We here report a case of TTS following a car accident. Typical apical ballooning with moderate reduction of left ventricular ejection fraction (LVEF) and increased level of pro-B-type natriuretic peptide (BNP) as well as slightly increased creatine kinase and troponin T values were found in this 76-year-old female patient, 6 h after a car accident. At 10 weeks follow-up, we observed a normalization of regional wall motion, LVEF, electrocardiogram and pro-BNP. TTS is an acute heart failure syndrome and an important differential diagnosis of acute coronary syndrome. PMID:27377800

  4. GRB 130427A: A Nearby Ordinary Monster

    Science.gov (United States)

    Maselli, A.; Melandri, A.; Nava, L.; Mundell, C. G.; Kawai, N.; Campana, S.; Covino, S.; Cummings, J. R.; Cusumano, G.; Evans, P. A.; Ghirlander, G.; Ghisellini, G.; Guidorzi, C.; Kobayashi, S.; Kuin, P.; La Parola, V.; Mangano, V.; Oates, S.; Barthelmy, S.; Gehrels, N.; Marshall, F.; Wiegand, B.

    2014-01-01

    Long-duration gamma-ray bursts (GRBs) are an extremely rare outcome of the collapse of massive stars and are typically found in the distant universe. Because of its intrinsic luminosity (L approx. 3 x 10(exp 53) ergs/s and its relative proximity (z = 0.34), GRB 130427A reached the highest fluence observed in the gamma-ray band. Here, we present a comprehensive multiwavelength view of GRB 130427A with Swift, the 2-meter Liverpool and Faulkes telescopes, and by other ground-based facilities, highlighting the evolution of the burst emission from the prompt to the afterglow phase. The properties of GRB 130427A are similar to those of the most luminous, high-redshift GRBs, suggesting that a common central engine is responsible for producing GRBs in both the contemporary and the early universe and over the full range of GRB isotropic energies.

  5. A cabeça voraz

    Directory of Open Access Journals (Sweden)

    Betty Mindlin

    1996-08-01

    Full Text Available o artigo focaliza um mito indígena sobre a cabeça voadora e voraz, registrado pela autora em vários grupos indígenas da Amazônia, como os Tupari, os Macurap, os Jabuti, os Aruá, os Sateré-Mawé. Cada versão do mito tem um enredo diferente, mas o tema intrigante é sempre o mesmo: a mutilação do corpo, a cabeça que se transforma ou cola-se num outro ser. Procura-se mergulhar no significado desse mito, ao qual Claude Lévi-Strauss dedicou boa parte de dois livros magistrais, A origem das maneiras da mesa e A oleira ciumenta, e que foi usado por Mário de Andrade no livro clássico sobre o herói brasileiro, Macunaína, uma das poucas obras de fição brasileira a se inspirar em temas e personagens míticos indígenas. O registro de campo desse mito é uma pequena ponta de um amplo trabalho de documentação da tradição e dos mitos indígenas brasileiros, que a autora vem realizando há alguns anos. A intenção, nesse texto, é compreender a riqueza do imaginário indígena brasileiro, insistir na necessidade de documentar culturas que são nossas contemporâneas e ainda bastante desconhecidas. A fição e a arte brasileiras poderiam ampliar muito o seu universo ao explorar e tentar compreender as raízes brasileiras que nos são dadas por mais de 200 povos indígenas do país. Também para os índios, escrever, contar, divulgar e usar nas próprias escolas os seus mitos é importante para reafirmar a identidade étnica e valorizar sua participação na sociedade brasileira.The article focuses an indian myth about a flying and voracious head, that was told to the author by several indian tribes from the Amazon, such as the Tupari, the Macurap, the Jabuti, the Aruá, the Sateré-Mawé. Each version has a different plot, but the intriguing theme is always the same: the mutilation of the body, a head that is transformed or attaches itself to another being. The essay delves into the meaning of this myth, to which Claude L

  6. A view to a (staged) kill?

    DEFF Research Database (Denmark)

    Gamborg, Christian; Jensen, Frank Søndergaard; Sandøe, Peter

    2015-01-01

    Is it acceptable, in principle, to shoot wild animals as a sport? The ethical controversy around recreational hunting is not only of academic interest but plays an important role in public and political discussions concerning the legitimacy of hunting. For the hunter, hunting is typically imbued...... with a perception of deeper meaning. For ardent non-hunters it may be hard to understand the meaning of enjoying nature by shooting at other living beings. This lack of mutual understanding makes it difficult to create a dialogue. However, the issue is not just about whether or not to accept hunting...... but also the specific forms of hunting. The aim of the paper is to explore the attitudes at stake in debates about a controversial form of hunting: shooting of birds that are farm reared and subsequently released for the purpose of being hunted. The paper is based on a nationally representative survey...

  7. Morphing a plasmonic nanodisk into a nanotriangle.

    Science.gov (United States)

    Schmidt, Franz P; Ditlbacher, Harald; Hofer, Ferdinand; Krenn, Joachim R; Hohenester, Ulrich

    2014-08-13

    We morph a silver nanodisk into a nanotriangle by producing a series of nanoparticles with electron beam lithography. Using electron energy loss spectroscopy (EELS), we map out the plasmonic eigenmodes and trace the evolution of edge and film modes during morphing. Our results suggest that disk modes, characterized by angular order, can serve as a suitable basis for other nanoparticle geometries and are subject to resonance energy shifts and splittings, as well as to hybridization upon morphing. Similar to the linear combination of atomic orbitals (LCAO) in quantum chemistry, we introduce a linear combination of plasmonic eigenmodes to describe plasmon modes in different geometries, hereby extending the successful hybridization model of plasmonics. PMID:25000389

  8. Education:a discipline or a field?

    Institute of Scientific and Technical Information of China (English)

    WANG Hongcai

    2007-01-01

    Historically,scholars have made unfailing efforts to position education as a standard science,but no solid success has been achieved regardless of the positivistic paradigm,quantitative approaches,or value-free neutral stances they adopted.In China,scholars have set up a so-called"three independency"standard for the scientific study of education,but it has been finally proved invalid in practice.As interdisciplines permeate the field of education,education experiences a crisis of being colonized.After serious rethinking,interdisciplines were widely believed to do more good than harm to education.Therefore,education is beginning to transform from a"colony"to an"empire".In this transformation,education finds it necessary to break the traditional disciplinary boundaries and make it a field in which interdisciplinary communication is contributory to the enrichment of scholarship.

  9. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Here's Help White House Lunch Recipes Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de una tomografía computada (video) CAT stands for "computerized axial tomography." Translated, that means ...

  10. Getting a CAT Scan

    Medline Plus

    Full Text Available ... Skiing, Snowboarding, Skating Crushes What's a Booger? Getting a CAT Scan (Video) KidsHealth > For Kids > Getting a CAT Scan (Video) Print A A A Text Size en español Obtención de ...

  11. Biodiesel: A fuel, a lubricant, and a solvent

    Science.gov (United States)

    Biodiesel is well-known as a biogenic alternative to conventional diesel fuel derived from petroleum. It is produced from feedstocks such as plant oils consisting largely of triacylglycerols through transesterification with an alcohol such as methanol. The properties of biodiesel are largely compet...

  12. A Year To Make a Difference

    Science.gov (United States)

    Howell, J. Emory

    1999-01-01

    Secondary School Feature Articles * Animating Reactions: A Low-Cost Activity for Particle Conceptualization at the Secondary Level, by Robert W. Milne, p 50. * The Gravity of the Situation, by Damon Diemente, p 55. You must be the change you wish to see in the world. Mahatma Ghandi The beginning of a new year always brings with it a feeling of anticipation, a desire to achieve new goals, and a certain urgency to accomplish. Beginning the last year of the 1900s seems somehow to amplify these feelings. This week I was reminded twice of the challenge that lies in focusing on those things that we can change and not being fettered by those we cannot. The first example occurred in my office on a Monday afternoon. A young woman was considering the choice between entering graduate school or seeking a high school teaching position. After approximately 10 years in the workforce, she had entered college and was now within a semester of graduation. While pursuing her studies she had served as a substitute teacher in her home community, believing the experience would affirm her longstanding desire to teach. The behavioral characteristics of some students seemed to be at odds with her memories of high school only a dozen years earlier. Now she was questioning whether she could make a difference in young lives or if she should give up the idea of teaching in high school in favor of graduate degrees in her discipline, which would lead to a career in post-secondary education. Although I assured her that she could indeed have a great impact on high school students, I empathized with the concern she was feeling. The second example occurred the same day, in a class for chemistry majors who are preparing to teach high school chemistry. While considering the importance of performance assessment, with discussion centered on a JCE article ((a href="//1998/jan/abs64.html">Rasp, S. L. J. Chem. Educ. 1998, 75, 64-66), one class member asked why we only discussed and read about what teachers

  13. Orbit of a Giant and a Dwarf

    Science.gov (United States)

    Kohler, Susanna

    2015-11-01

    The binary system Procyon, located a mere 11 light-years away, consists of a bright, subgiant star and a faint white dwarf presenting a distinct challenge for astronomers to observe. But careful analysis of two decades of precise measurements with the Hubble Space Telescope has now finally revealed some of its secrets.Challenging ObservationsPerturbations were detected as early as 1844 in the orbit of Procyon, originally thought to be a single star. Astronomers of the time suspected that this wobbling was due to the pull of a companion orbiting Procyon, but it wasnt until five decades later that the companion was first detected visually.Why? Because the subgiant Procyon A is the 8th brightest star in the sky. Its companion, on the other hand, is a white dwarf thats fainter (in visual wavelengths) by a factor of nearly 16,000! And the two stars are separated by an angular distance of less than 5.Due to the difficulty observing the system, the measurements of its motion and resulting estimates of the masses of the two stars have been a subject of debate for the better part of the last century.Led by Howard Bond (Pennsylvania State University and the Space Telescope Science Institute), a team of astronomers has now analyzed two decades of Hubble observations of the system, combined with historical, ground-based observations dating back to the 19th century. Bond and collaborators used these data to precisely measure the orbital elements of Procyon and obtain dynamical masses of the two stars.Surprising MixingRelative orbit of Procyon B around Procyon A. The red curve is the authors fit to the orbit, and the open blue circles are positions predicted by the orbital elements found. The black dots are the HST observations of Procyon B. The open green and turquoise circles are the (significantly less precise!) historical, ground-based observations. [Bond et al. 2015]The team reports that this system orbits once every 40.8 years. They find masses for the two stars of 1

  14. A geomechanical model of a sinkhole formation

    Science.gov (United States)

    Danchiv, Alexandru; Zamfirescu, Florian; Mocuta, Marius; Popa, Iulian; Zlibut, Alexandru; Huggenberger, Peter; Zechner, Eric; Dresmann, Horst; Scheidler, Stefan; Wiesmeier, Stefan

    2016-04-01

    On December 2010 a sinkhole was suddenly formed close to the eastern flank of Ocna-Mures salt dome. Soon after the collapse the sinkhole was filled with brine forming a salt lake called Plus Lake. The total volume of sinkhole of about 100000 m3 remained constant since February 2011. The Ocna Mures salt dome is situated on the western border of the Transylvanian basin (Romania) and has been exploited for a long time. The ceilings of some shallow mine chambers are now collapsed and filled with brine. Along the eastern flank of the salt dome there is a disturbed zone due to diapirism. Its presence is suggested by the strong fragmentation of rock in the boreholes drilled along the salt-sterile contact, as it resulted from the low values of RQD index. The sinkhole is probably due to a pressure increase along the diapir flank. The causes of this sudden increase of pressure are not well known. Most probably it is due to the damage of the tubing of a flank borehole as mentioned in a technical report of the exploiting company. The injected fresh water expelled through the breaches of the damaged borehole and, due to the high pressure flushed up the crushed material of the disturbed zone. In order to better understand the setting up of the Plus Lake joint research efforts were performed by teams from Bucharest and Basel Universities since 2013. For the geomechanical approach a numerical model was performed using the Flac 7.0 code. In a first stage the creep behavior of salt was analyzed considering a Norton creep law. It resulted that after 100 years the salt reached equilibrium, the creep could be neglected and in a first approximation mechanical equilibrium could be analyzed considering only an elasto-plastic behavior of both the salt and the sterile. For both the salt and the surrounding sedimentary rocks the Mohr-Coulomb criterion was considered. The properties of sterile rocks were estimated following the GSI system. Due to poor rock quality the strength parameters have

  15. A reductive coupling strategy towards ripostatin A

    Directory of Open Access Journals (Sweden)

    Kristin D. Schleicher

    2013-07-01

    Full Text Available Synthetic studies on the antibiotic natural product ripostatin A have been carried out with the aim to construct the C9−C10 bond by a nickel(0-catalyzed coupling reaction of an enyne and an epoxide, followed by rearrangement of the resulting dienylcyclopropane intermediate to afford the skipped 1,4,7-triene. A cyclopropyl enyne fragment corresponding to C1−C9 has been synthesized in high yield and demonstrated to be a competent substrate for the nickel(0-catalyzed coupling with a model epoxide. Several synthetic approaches toward the C10−C26 epoxide have been pursued. The C13 stereocenter can be set by allylation and reductive decyanation of a cyanohydrin acetonide. A mild, fluoride-promoted decarboxylation enables construction of the C15−C16 bond by an aldol reaction. The product of this transformation is of the correct oxidation state and potentially three steps removed from the targeted epoxide fragment.

  16. Birth of a theorem a mathematical adventure

    CERN Document Server

    Villani, Cédric

    2015-01-01

    This man could plainly do for mathematics what Brian Cox has done for physics" (Sunday Times). What goes on inside the mind of a rock-star mathematician? Where does inspiration come from? With a storyteller's gift, Cedric Villani takes us on a mesmerising journey as he wrestles with a new theorem that will win him the most coveted prize in mathematics. Along the way he encounters obstacles and setbacks, losses of faith and even brushes with madness. His story is one of courage and partnership, doubt and anxiety, elation and despair. We discover how it feels to be obsessed by a theorem during your child's cello practise and throughout your dreams, why appreciating maths is a bit like watching an episode of Columbo, and how sometimes inspiration only comes from locking yourself away in a dark room to think. Blending science with history, biography with myth, Villani conjures up an inimitable cast of characters including the omnipresent Einstein, mad genius Kurt Godel, and Villani's personal hero, John Nash. Bir...

  17. Grasshoppers as a food source? A review

    Directory of Open Access Journals (Sweden)

    Paul, A.

    2016-01-01

    Full Text Available Description of the subject. Current trends suggest an increasing future demand for conventional meats, which indicates a strong need to shift this dependency to other alternative protein sources such as insects. Literature. From a nutritional point of view, of all the insects consumed globally, grasshoppers are particularly important as a human food. Data from the literature regarding the nutrient composition, amino acid profile, fatty acid profile, mineral composition and vitamin content of grasshoppers as reviewed in this paper, suggest that a number of grasshopper species are a good source of nutrients. It also highlights some of the health related aspects that might arise from the consumption of grasshoppers, mostly linked to agricultural practices and the allergic response of sensitive individuals. The paper also summarizes some religious, social and economic factors that are associated with grasshopper consumption. Conclusions. The success of introducing grasshoppers as a novel food in western countries depends on changes in consumer attitudes. It would be interesting to develop food products derived from grasshoppers in a form acceptable to consumers. Furthermore, it is important to explore the food potential of some grasshopper species native to western countries and to develop their rearing methodologies to enhance availability.

  18. PSYCHOTHERAPY FOR A SPORTS PERSON: A REVIEW

    Directory of Open Access Journals (Sweden)

    Kumudlata Singh

    2015-04-01

    Full Text Available Sports is all forms of usually competitive physical activity which, through casual or organized participation, aim to use, maintain or improve physical ability and skills while providing entertainment to participants, and in some cases, spectators. Sport participation can contribute to the development of social skills and self esteem, emotional well-being, social connectedness, and lead to a reduction in stress and improved mental health (Steptoe & Butler, 1996; Bailey, 2006; Asztalos et al., 2008; Armstrong & Oomen-Early, 2009. However, at higher levels of athletics, and in collegiate settings where pressures placed on the athlete are not just sport-related, athletes may be at risk for developing emotional and psychological problems. Sports psychology concerns with both psychological factors that influence participation and performance in sport and exercise as well as psychological effects derived from them. This is a study in the theory and philosophy of Psychotherapy. The focus is on the psychotherapeutic technique of reframing – a technique for helping sportsmen to see their situation in a new light, from a new perspective. Psychotherapy is the treatment by psychological means of the problem of an emotional nature, in which a trained person deliberately establishes a professional relationship with the patient.

  19. ViA: a perceptual visualization assistant

    Science.gov (United States)

    Healey, Chris G.; St. Amant, Robert; Elhaddad, Mahmoud S.

    2000-05-01

    This paper describes an automated visualized assistant called ViA. ViA is designed to help users construct perceptually optical visualizations to represent, explore, and analyze large, complex, multidimensional datasets. We have approached this problem by studying what is known about the control of human visual attention. By harnessing the low-level human visual system, we can support our dual goals of rapid and accurate visualization. Perceptual guidelines that we have built using psychophysical experiments form the basis for ViA. ViA uses modified mixed-initiative planning algorithms from artificial intelligence to search of perceptually optical data attribute to visual feature mappings. Our perceptual guidelines are integrated into evaluation engines that provide evaluation weights for a given data-feature mapping, and hints on how that mapping might be improved. ViA begins by asking users a set of simple questions about their dataset and the analysis tasks they want to perform. Answers to these questions are used in combination with the evaluation engines to identify and intelligently pursue promising data-feature mappings. The result is an automatically-generated set of mappings that are perceptually salient, but that also respect the context of the dataset and users' preferences about how they want to visualize their data.

  20. Tesla - A Flash of a Genius

    Science.gov (United States)

    Teodorani, M.

    2005-10-01

    This book, which is entirely dedicated to the inventions of scientist Nikola Tesla, is divided into three parts: a) all the most important innovative technological creations from the alternate current to the death ray, Tesla research in fundamental physics with a particular attention to the concept of "ether", ball lightning physics; b) the life and the bright mind of Nikola Tesla and the reasons why some of his most recent findings were not accepted by the establishment; c) a critical discussion of the most important work by Tesla followers.

  1. A certain ambiguity a mathematical novel

    CERN Document Server

    Suri, Gaurav

    2010-01-01

    While taking a class on infinity at Stanford in the late 1980s, Ravi Kapoor discovers that he is confronting the same mathematical and philosophical dilemmas that his mathematician grandfather had faced many decades earlier--and that had landed him in jail. Charged under an obscure blasphemy law in a small New Jersey town in 1919, Vijay Sahni is challenged by a skeptical judge to defend his belief that the certainty of mathematics can be extended to all human knowledge--including religion. Together, the two men discover the power--and the fallibility--of what has long been considered the pinn

  2. A SEISMIC SIGNATURE OF A SECOND DYNAMO?

    International Nuclear Information System (INIS)

    The Sun is a variable star whose magnetic activity varies most perceptibly on a timescale of approximately 11 years. However, significant variation is also observed on much shorter timescales. We observe a quasi-biennial (2 year) signal in the natural oscillation frequencies of the Sun. The oscillation frequencies are sensitive probes of the solar interior and so by studying them we can gain information about conditions beneath the solar surface. Our results strongly point to the 2 year signal being distinct and separate from, but nevertheless susceptible to the influence of, the main 11 year solar cycle.

  3. Aproximaciones a la Econometría

    OpenAIRE

    Antoni ESPASA

    1994-01-01

    En la concepción de la Econometría pueden adoptarse básicamente dos tipos de enfoques, que corresponden a dos formas distintas de concebir esta disciplina. Esta nota se hace eco de los comentarios críticos que la orientación econométrica basada en el supuesto de que las relaciones económicas son exactas ha recibido en la literatura, y se alinea en la corriente econométrica que se ha venido desarrollando a partir del trabajo pionero de Haavelmo (1944). Sobre esta publicación se puede decir, ut...

  4. From a Fratricide to a Family Memory

    OpenAIRE

    Riina Haanpää

    2008-01-01

    When a research deals with researcher’s own family history, a significant challenge is presented: “What is the significance of the familiarity the researcher has for their object of research? What is the researcher’s role and how their own memories influence their work?” In this article I explore the possibilities my own family history offers by observing a fratricide that took place in my family, as well as the narrations it has created. My grandfather’s brother...

  5. Who has a child as a teenager?

    OpenAIRE

    Ermisch, John; Pevalin, David J.

    2003-01-01

    This paper uses data from the British Household Panel Survey (BHPS) and the British 1970 Cohort Study (BCS70) to investigate the family background and childhood factors that are associated with having a child as a teenager. The advantage of combining results from these two sets of data is that the BHPS analyses are restricted to a few background factors while the BCS70 analyses have far more. However, the results obtained from the BHPS data are reasonably replicated with the BCS70 data in tha...

  6. A Conversation with Richard A. Olshen

    OpenAIRE

    Rice, John A.

    2015-01-01

    Richard Olshen was born in Portland, Oregon, on May 17, 1942. Richard spent his early years in Chevy Chase, Maryland, but has lived most of his life in California. He received an A.B. in Statistics at the University of California, Berkeley, in 1963, and a Ph.D. in Statistics from Yale University in 1966, writing his dissertation under the direction of Jimmie Savage and Frank Anscombe. He served as Research Staff Statistician and Lecturer at Yale in 1966–1967. ¶ Richard accepted a facult...

  7. A growth model in a random environment

    OpenAIRE

    Gravner, Janko; Tracy, Craig A.; Widom, Harold

    2002-01-01

    We consider a model of interface growth in two dimensions, given by a height function on the sites of the one--dimensional integer lattice. According to the discrete time update rule, the height above the site $x$ increases to the height above $x-1$, if the latter height is larger; otherwise the height above $x$ increases by 1 with probability $p_x$. We assume that $p_x$ are chosen independently at random with a common distribution $F$, and that the initial state is such that the origin is fa...

  8. Radon: a friend or a foe?

    International Nuclear Information System (INIS)

    Radon has two facets. On the one hand, it poses grave health hazards to not only uranium miners but also people living in normal houses and buildings. On the other hand, it helps in mineral exploration, earthquake prediction, study of volcanic activities, and search for geothermal energy sources. Some of the characteristics of radon are now well known, while others are yet to be explored. It has proved to be a good friend and a powerful enemy at the same time. This paper is a brief introduction of the potential benefits and possible threats of radon and its daughters. (author)

  9. Dialog between a Lexicographer and a Translator

    Directory of Open Access Journals (Sweden)

    Mark Kit

    2015-06-01

    Full Text Available Dialog between a Lexicographer and a TranslatorThe discussion between the authors of the paper concerns the most pressing issues encountered in natural language semantics, as well as in corpus linguistics and computational linguistics. A broad range of knowledge, allowing linguists and information scientists to work together, is required in these areas. The paper describes some primary problems of human and machine translation caused by gaps between different fields of knowledge. The authors suggest that interdisciplinary approach is required when it comes to contrastive studies in linguistics.

  10. A mathematical model for a gaming community

    CERN Document Server

    Breban, Romulus

    2016-01-01

    We consider a large community of individuals who mix strongly and meet in pairs to bet on a coin toss. We investigate the asset distribution of the players involved in this zero-sum repeated game. Our main result is that the asset distribution converges to the exponential distribution, irrespective of the size of the bet, as long as players can never go bankrupt. Analytical results suggests that the exponential distribution is a stable fixed point for this zero-sum repreated game. This is confirmed in numerical experiments.

  11. Are You a Man or a Mouse?

    DEFF Research Database (Denmark)

    Herrmann, Janne Rothmar

    2008-01-01

    British researchers in applications to the British regulator, HFEA (the Human Fertilisation and Embryology Authority) sparked worldwide debate and controversy reflecting a fear that this type of research was a slippery slope towards creating actual beings that were part human and part animal. The...... scientific community was, however, successful in explaining to both the public and policy-makers that this new technique did in fact not entail the creation of actual live interspecies beings, but rather provided a way forward in studying diseases in the petri dish and thereby improving chances of offering...

  12. A School Day is a School Day

    DEFF Research Database (Denmark)

    Engelhardt, Robin

    2007-01-01

    : Compared with the French communities, where many children have to repeat a year if they fail the tests, the children in the Flemish communities get a lot of help if they risk failing. In the beginning of the first school year, the students can do their homework in the school together with their own classes......Life of Science, edited by Lykke Margot Ricard and Robin Engelhardt. Learning Lab Denmark, Copenhagen, pages 7-13. 2003 Short description: The school Sint-Jozef-Klein-Seminarie in the Flemish town of Sint-Niklaas reveals a school system characterised by hard work, solicitude and tradition. Abstract...

  13. A case study, Bagnoli: a difficult transition

    Directory of Open Access Journals (Sweden)

    Maria Antonietta Selvaggio

    2015-01-01

    In this research work we intend to verify how a particular physical-spatial dimension has influenced the social relations and the same identities of the people and their “community”, how we can delineate the perception and the performance of a urban transformation largely failed, and which contribution the citizens of Bagnoli can give to the urban design through their own imaginary and meanings they ascribe to their environment (Lynch 1960. In this sense, the study aim at giving a contribution to the participative practice, that up to now is out of the transition dynamics.

  14. A suspended rope wrapped around a cylinder

    International Nuclear Information System (INIS)

    The problem of a suspended rope wrapped around a fixed cylinder is studied. If the suspension force is larger than a certain threshold (which is larger than the weight of the rope), the rope would remain tightly wrapped around the cylinder. For suspension forces smaller than that threshold but larger than another threshold, the rope becomes loose (loses contact with the cylinder) at some points, but still remains at rest. These thresholds are obtained when there is no friction. The system is then analysed also with friction, and the threshold of tight-wrapping is obtained for that case as well. (paper)

  15. Vampire as a metaphor

    Directory of Open Access Journals (Sweden)

    Jovanović Bojan G.

    2004-01-01

    Full Text Available A vampire, as a demonized deceased human, is used as a specific metaphor to explain unknown sources of various troubles in a community. A malicious deceased one is a mythical creature and as such is to blame for the existing troubles in a community; the creature, in turn, becomes a subject i.e., a victim in a ritual performed to avert the difficulties, so that the community in question could return to its daily life. A myth revival establishes diagnosis and appropriate therapy for the crisis solving. On the other hand, during the next crisis a vampire as a part of the mythical and ritual pattern becomes a troublemaker again.

  16. Managing a Voluntary Organisation

    OpenAIRE

    Dk. Hjh. Siti Fatimah - Pg. Hj. Petra

    2014-01-01

    This paper reveals the experience of a young member of a non-profitable organisation in managing a team of professionals in Brunei Darussalam. In a team, the experience of managing has not been as scary as expected; positions taken, however, must be firm and effective. Being a leader of the contingency approach type, actions and responses are based on circumstances. Marketing and managing changes need to be pursued as a new leader of a voluntary organization. Careful considerations and risks ...

  17. A theory of knowledge

    OpenAIRE

    1993-01-01

    In this dissertation I present a new solution to the renowned Gettier problem. My solution, which in a sense represents a defense of a rather traditional epistemological approach, is based upon a distinction between primary and secondary beliefs. I argue that primary beliefs are known if justified and true, whereas secondary beliefs are known iff they are believed on the basis of a known primary belief. Much emphasis is put upon defending this approach against potential objections, but I a...

  18. A Planck Vacuum Cosmology

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2009-04-01

    Full Text Available Both the big-bang and the quasi-steady-state cosmologies originate in some type of Planck state. This paper presents a new cosmological theory based on the Planck- vacuum negative-energy state, a state consisting of a degenerate collection of negative- energy Planck particles. A heuristic look at the Einstein field equation provides a con- vincing argument that such a vacuum state could provide a theoretical explanation for the visible universe.

  19. A spacetime cloak, or a history editor

    International Nuclear Information System (INIS)

    We introduce a new type of electromagnetic cloak, the spacetime cloak (STC), which conceals events rather than objects. Non-emitting events occurring during a restricted period are never suspected by a distant observer. The cloak works by locally manipulating the speed of light of an initially uniform light distribution, whilst the light rays themselves always follow straight paths. Any 'perfect' spacetime cloak would necessarily rely upon the technology of electromagnetic metamaterials, which has already been shown to be capable of deforming light in ways hitherto unforeseen—to produce, for example, an electromagnetic object cloak. Nevertheless, we show how it is possible to use intensity-dependent refractive indices to construct an approximate STC, an implementation that would enable the distinct signature of successful event cloaking to be observed. Potential demonstrations include systems that apparently violate quantum statistics, 'interrupt-without-interrupt' computation on convergent data channels and the illusion of a Star Trek transporter

  20. A feasibility study of a thermosyphoning rig

    International Nuclear Information System (INIS)

    This report covers the work performed to generate a conceptual design of a thermosyphoning test facility. Scaling methods have been reviewed; and a two phase scaling technique has been applied to determine the geometry and specifications of the facility. The instrumentation and the data acquisition systems have been defined such as to provide the most needed information on two phase thermosyphoning phenomena. Particular attention has been paid to the scaling of the primary heat transport system which consists of a figure-of-eight loop with five channels per pass and seven half-length, full-diameter heater elements per channel. The facility can be defined as 'half-length, half-height facility' with decay power capabilities for the primary system and full power for the secondary system

  1. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health What is Orofacial Pain? What is a Composite Resin (White Filling)? Why is Oral Health Important for Men? Are You Biting Off More ...

  2. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Oral Health Important for Men? When Should My Child First See a Dentist? What is Dental Amalgam (Silver Filling)? ... Statement | Terms and Conditions © 1996-2016 Academy of General Dentistry. All Rights Reserved.

  3. A certified private practice - a report

    International Nuclear Information System (INIS)

    Based on the requirements for internal quality assurance in our private practice a model for quality management was implemented. Using such a quality management system (QM-system) resulted in a systematic optimization and higher quality of operating procedures in all work areas. The realization of the new QM-system led to a higher transparency, improved economical efficiency, and an increase in personal motivation. Internal frictional losses could be effectively reduced saving time and money. The efforts in time, costs and personal resources during implementation of the QM-system, which had been considered as downsides in the beginning, are outweighed by the benefits by far according to our experience. In summary: ''We consider it worthwhile in all respects''. (orig.)

  4. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Sunday, August 28, 2016 About | ... More Than You Can Chew? How Do I Care for My Child's Baby Teeth? What is a ...

  5. What Makes a Wetland a Wetland?

    Science.gov (United States)

    Naturescope, 1986

    1986-01-01

    Provides descriptions of and activities about various kinds of wetlands. Contains seven learning activities ranging from creating wetland scenes with picture cutouts to actually exploring a wetland. Includes reproducible handouts and worksheets for several of the activities. (TW)

  6. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available Dental care and oral health information you need from the Academy of General Dentistry Wednesday, June 08, ... Orofacial Pain? Temporomandibular Joint Disorder Learn what those dental words mean. The Life of a Tooth games ...

  7. A Strange M\\`enage \\'A Trois

    OpenAIRE

    Bergh, Sidney van den

    2010-01-01

    The Magellanic Clouds may have joined our Milky Way system quite recently. The Large Magellanic Cloud turns out to be a remarkably luminous object that is close to the upper luminosity limit of the class of magellanic irregular galaxies.

  8. PNEUMOCONIOSIS IN A SPOONBILL - A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Shivaji Bhattacharya

    2013-12-01

    Full Text Available Pneumoconiosis has been identified in an adult dead spoonbill (Platalea leucorodia from a Zoo in Kolkata, West Bengal, India. An environmental automobile pollutants present around that ambient may be the cause of pneumoconiosis.

  9. A thing finished is a thing dead

    DEFF Research Database (Denmark)

    Baumeister, Ruth

    2014-01-01

    The article gives a general overview of Asger Jorn´s position in architecture. Besides his theoretical stands, it exemplifies his position by showing the artist´s private house and garden in Albissola, Italy....

  10. Can a Humean be a Contractarian?

    Directory of Open Access Journals (Sweden)

    Robert Sugden

    2009-01-01

    Full Text Available In this paper I argue, contrary to Hartmut Kliemt, that it is possible to be both a Humean and, in James Buchanan's sense, a contractarian. Hume sees principles of justice and political allegiance not as actual or hypothetical products of explicit agreement, but as conventions that have emerged spontaneously. However, it is fundamental to Hume's analysis that conventions are mutually advantageous, and hence cognate with agreements. The core idea in Buchanan's contractarianism is that the proper role of government is to implement voluntary exchanges between individuals, not to define and maximise a unified conception of social welfare. Although real politics cannot be based entirely on unanimous agreement, the voluntary exchange approach provides a valuable structure for normative economics.

  11. Packing a cake into a box

    CERN Document Server

    Skopenkov, Mikhail

    2010-01-01

    Given a cake in form of a triangle and a box that fits the mirror image of the cake, how to cut the cake into a minimal number of pieces so that it can be put into the box? The cake has an icing, so that we are not allowed to put it into the box upside down. V.G. Boltyansky asked this question in 1977 and showed that three pieces always suffice. In this paper we provide examples of cakes that cannot be cut into two pieces to put into the box. This shows that three is the answer to V.G. Boltyansky's question. Also we give examples of cakes which can be cut into two pieces.

  12. A man with a worrying potassium deficiency

    OpenAIRE

    Tabasum, A; Shute, C; Datta, D.; George, L

    2014-01-01

    Summary Hypokalaemia may present as muscle cramps and Cardiac arrhythmias. This is a condition commonly encountered by endocrinologists and general physicians alike. Herein, we report the case of a 43-year-old gentleman admitted with hypokalaemia, who following subsequent investigations was found to have Gitelman's syndrome (GS). This rare, inherited, autosomal recessive renal tubular disorder is associated with genetic mutations in the thiazide-sensitive sodium chloride co-transporter and ma...

  13. A Mainstreaming: Analysis of a Policy Instrument

    OpenAIRE

    Halpern, Charlotte; Jacquot, Sophie; Le Galès, Patrick

    2008-01-01

    In the world of public policy, waves of innovations and new policy developments are usually followed by movements of rationalisation. Most policy domains, in the EU as elsewhere, progressively become institutionalised, a sedimentation of institutions and policy instruments progressively creating a mille feuilles within which contradictions take place, hence the drive in due course either to add another layer, to change the institution or to create new instruments to rationalise existing on...

  14. A note on a walrus’ European odyssey

    Directory of Open Access Journals (Sweden)

    E W Born

    2014-02-01

    Full Text Available This study reports on the first successful identification of the site of origin of an extralimital walrus in Europe. On 24 February 2010 an adult male Atlantic walrus (Odobenus rosmarus rosmarus migrant was instrumented with a SPOT-5 satellite-linked transmitter (SLT while hauled out on a beach on the Faroe Islands at 62° 15' N/06° 32' W. This SLT transmitted until 5 March during which period the walrus made local movements, likely for feeding. Transmissions were not received during 6-25 March, however, visual observations during this time indicated that the walrus remained at the Faroe Islands. A second transmitter was deployed on the same animal on 25 March 2010 at another site on the islands (62° 16' N/07° 04' W. Activity data collected over 13 days indicated that the walrus hauled out in three different places in the Faroe Islands and used a total of 24% of its time resting on land.  On 29 March 2010 the walrus left the Faroe Islands and headed WNW towards NE Iceland. On 2 April it took a NNE course and swam towards Svalbard where the last location was received from a sea ice covered area on 25 April 2010 at 78° 27' N/09° 20' E (i.e. ca. 40 km west of the island of Prins Karls Forland in the western Svalbard archipelago. During 29 March-22 April the walrus swam a minimum distance of 2216 km between the last location at the Faroe Islands and the first location at Svalbard, with an average swimming speed of 4.5 km/h. A genetic analysis indicated that this walrus belonged to the Svalbard-Franz Josef Land subpopulation, thereby confirming that it returned to its site of origin.

  15. A Reminder and a Memorial [Book Review

    Directory of Open Access Journals (Sweden)

    Alfred White Franklin

    2009-09-01

    Full Text Available Originally published in the British Medical Journal on March 22, 1980, Volume 280, pages 851-855. The Quality of Life: the Peckham Approach to Human Ethology. Innes H Pearse. (Pp 194; £6 50. Scottish Academic Press.1979. The biologist studies man as a physical organism existing in a space-time world of measurable dimensions. This organism has the ability to adapt to changes in its environment; to the processes ofgrowth, development and aging; and to disease. The main objectives of medicine have been to help both adaptation and defence. Prevention through hygiene and immunisation, drugs, surgical removals, and replacements-all these make their contributions, which have increased in complexity and expense, disappointing Beveridge's hope in 1949 that a National Health Service plus rehabilitation (then a novelty would so improve health that the Service would wither away. To avoid and prevent ill health are worthy aims; to promote health is also worthy, but something different. It was to study healthy living that Dr Scott Williamson, Dr Innes Pearse, and their colleagues devised the Peckham experiment, of which this book is at once a reminder and a memorial. They wanted to study Homo sapiens in his natural habitat and they began their exploration as biologists. In an initial family club of 150 families they noted that disorders, however skilfully treated, recurred in the environment out of which the disorder had arisen. So, in 1935, they designed a laboratory in which human beings could be observed growing up and creating new families. The centre, purpose-built, combined maximum visibility throughout, flexibility, and free access to all members. By the outbreak of war 800-900 families had grown their own lively social life. Many of the original families rejoined when the centre reopened after the war. It finally closed in 1951. Meanwhile, the observers had invented a new role.

  16. What a Difference a Bank Makes

    OpenAIRE

    Klaus, Alexander; Marie, Ségolène

    2006-01-01

    Nowadays, the service industry, especially banks, faces increasing competition. In such environment, differentiation is necessary. The general purpose of this thesis is to understand how a bank can achieve differentiation based on a marketing approach. Two research questions will respectively examine the three additional P’s of the marketing mix (People, Presentation or Physical Evidence and Process) and the Customer Relationship Management as possible differentiators. To fulfill the purpose,...

  17. A toolkit for a generative lexicon

    OpenAIRE

    Henry, Patrick; Bassac, Christian

    2008-01-01

    poster - 6 pages International audience In this paper we describe the conception of a software toolkit designed for the construction, maintenance and collaborative use of a Generative Lexicon. In order to ease its portability and spreading use, this tool was built with free and open source products. We eventually tested the toolkit and showed it filters the adequate form of anaphoric reference to the modifier in endocentric compounds.

  18. Nagele, a green building without a roof

    OpenAIRE

    Abad Monllor, Enrique

    2014-01-01

    The paper shows the design process of Nagele, a Dutch modernist agrarian settlement designed during the Post-Second World War period by the internationally recognized group of architects De 8 en Opbouw: Rietveld, Van Eesteren, Merkelbach, van Eyck, Bakema, Stam, Ruys, etc. It is located in the Noordoostpolder (NOP), in the Flevoland province, which was entirely reclaimed from the sea. The country planning of the Noodoostpolder reveals a high rationalization in the disposal of roads, canals, ...

  19. A balanced psychology and a full life.

    OpenAIRE

    Martin E. P. Seligman; Parks, Acacia C; Steen, Tracy

    2004-01-01

    Psychology since World War II has been largely devoted to repairing weakness and understanding suffering. Towards that end, we have made considerable gains. We have a classification of mental illness that allows international collaboration, and through this collaboration we have developed effective psychotherapeutic or pharmacological treatments for 14 major mental disorders. However, while building a strong science and practice of treating mental illness, we largely forgot about everyday wel...

  20. A Vision For A Land Observing System

    Science.gov (United States)

    Lewis, P.; Gomez-Dans, J.; Disney, M.

    2013-12-01

    In this paper, we argue that the exploitation of EO land surface data for modelling and monitoring would be greatly facilitated by the routine generation of inter- operable low-level surface bidirectional reflectance factor (BRF) products. We consider evidence from a range of ESA, NASA and other products and studies as well as underlying research to outline the features such a processing system might have, and to define initial research priorities.

  1. A museum, the city, and a nation

    OpenAIRE

    Lepawsky, Joshua

    2008-01-01

    Abstract The purpose of this article is to understand how a corporate museum in Kuala Lumpur, Malaysia works to create proleptic myths of nationhood to under-gird a broader state-centric project of nationalist?capitalist modernization. The article examines how these myths are expressed in the museum's design plans and are manifested in the museum's displays and spatial layout. From this analysis it becomes apparent that, first, the museum's designers intend for Malaysian museum-goe...

  2. A proposal of a local modified QCD

    CERN Document Server

    de Oca, Alejandro Cabo Montes

    2012-01-01

    A local and renormalizable version of a modified PQCD introduced in previous works is presented. The construction indicates that it could be equivalent to massless QCD. The case in which only quark condensate effects are retained is discussed in more detail. Then, the appearing auxiliary fermion fields can be integrated leading to a theory with the action of massless QCD, to which one local and gauge invariant Lagrangian term for each quark flavour is added. These terms are defined by two gluon and two quark fields, in a form curiously not harming power counting renormalizability. The gluon self-energy is evaluated in second order in the gauge coupling and all orders in the new quark couplings, and the result became transversal as required by the gauge invariance. The vacuum energy was calculated in the two loop approximation and also became gauge parameter independent. The possibilities that higher loop contributions to the vacuum energy allow the generation of a quark mass hierarchy as a flavour symmetry br...

  3. Acute hypervitaminosis A in a young lady.

    Science.gov (United States)

    Khasru, M R; Yasmin, R; Salek, A K; Khan, K H; Nath, S D; Selim, S

    2010-04-01

    Acute vitamin A toxicity from a large dose has been reported to cause pseudotumour cerebri. Usually it is common in children. Herein we present the case of a young lady of 18 years old with the complaints of headache, vomiting, back pain and diplopia after ingestion of high dose (about 10 million international units) vitamin A capsule intentionally at a time due to some family problems. She gave no history of fever, convulsion, unconsciousness, pain in eyes, difficulties in walking and jaundice or any urinary problem during this illness. On query she gave no history of taking any other drugs including oral contraceptive and tetracycline & steroids. She also gave no history of sleep disorder. There was bilateral papilloedema, pupils were a bit dilated symmetrically but reacting to light, visual acuity 6/60 on left eye and 6/18 on right eye and bilateral 6th cranial nerve palsy more marked on left side. MRI of brain and orbits showed normal study. Patient improved after giving acetazolamide. PMID:20395929

  4. De Analogía a Digitalia

    Directory of Open Access Journals (Sweden)

    Dr. Xaime Fandiño Alonso

    2001-01-01

    Full Text Available La transformación hacia la tecnología numérica ha provocado en el último decenio cambios importantes en los entornos de creación, operación, transformación y distribución de productos audiovisuales.Los restos de la era analógica están dando sus últimos estertores de la mano de unos entornos digitales, desarrollados velozmente.Estos nuevos equipos son en la mayoría de los casos prototipos. La velocidad del mercado, la competencia, las joint-ventures..., no permiten ningún tipo de relajo a las empresas tecnológicas que participan en esta carrera desenfrenada de competitividad.Las maquinarias dedicadas a procesos puntuales, cada vez más, son historias para el recuerdo. Hoy todo es efímero y la tecnología de antaño basada en equipos mecánicos (magnetoscopios..., plataformas y soportes lineales (cintas... están abocados a la desaparición.Conceptos de solvencia empresarial tales como "los grandes y los pequeños", utilizados en otros ámbitos de la industria, son en el sector audiovisual cada vez más delicados. En los diarios económicos podemos leer cómo, con cierta asiduidad, empresas muy posicionadas en el sector se ven abocadas a establecer fusiones, compras y participaciones, con pequeñas células de creación y desarrollo que surgen de la creatividad de jóvenes emprendedores, hasta ayer desconocidos.La era digital está corriendo un enorme telón y deja atrás, por suerte, una etapa analógica en la que la posesión de los medios de producción, debido a sus costes, era motivo suficiente para negar la participación y el acceso, a equipos tecnológicos audiovisuales de carácter profesional, a los creadores.Hoy, lo digital proporciona nuevos sistemas con entornos productivos más amables a la vez que reduce considerablemente coste de los equipamientos. En este momento, despojados ya de los inconvenientes analógicos, el talento es el verdadero motor de la industria audiovisual, en un sector que aglutina tecnología

  5. Dispersive optomechanics: a membrane inside a cavity

    International Nuclear Information System (INIS)

    We present the results of theoretical and experimental studies of dispersively coupled (or 'membrane in the middle') optomechanical systems. We calculate the linear optical properties of a high finesse cavity containing a thin dielectric membrane. We focus on the cavity's transmission, reflection and finesse as a function of the membrane's position along the cavity axis and as a function of its optical loss. We compare these calculations with measurements and find excellent agreement in cavities with empty-cavity finesses in the range 104-105. The imaginary part of the membrane's index of refraction is found to be ∼10-4. We calculate the laser cooling performance of this system, with a particular focus on the less-intuitive regime in which photons 'tunnel' through the membrane on a timescale comparable to the membrane's period of oscillation. Lastly, we present calculations of quantum non-demolition measurements of the membrane's phonon number in the low signal-to-noise regime where the phonon lifetime is comparable to the QND readout time.

  6. A leitura: um passaporte para a vida

    Directory of Open Access Journals (Sweden)

    Armindo Teixeira Mesquita

    2011-06-01

    Full Text Available Nas sociedades actuais, a capacidade para usar material escrito é indispensável ao acesso a todo tipo de informação, tornando o uso da leitura cada vez mais necessário à participação real do cidadão em actividades produtivas e colectivas, porque ajuda a formar seres pensantes. O contacto com os livros deve ser iniciado o mais cedo possível, não só pelo manuseio, como também pela história contada ou pelos jogos rítmicos. Com efeito, na idade da infância, toda a energia do indivíduo é dirigida para a construção da sua identidade. Logo, as primeiras leituras entram no período da formação e da fundação, isto é, consignamos à leitura uma grande força de desenvolvimento pessoal. Os livros, para além de auxiliares na aprendizagem do mundo, formam o leitor no gosto. Formar o gosto e possibilitar escolhas são realidades fundamentais na vida adulta.

  7. A Cooperation Model Applied in a Kindergarten

    Directory of Open Access Journals (Sweden)

    Jose I. Rodriguez

    2011-10-01

    Full Text Available The need for collaboration in a global world has become a key factor for success for many organizations and individuals. However in several regions and organizations in the world, it has not happened yet. One of the settings where major obstacles occur for collaboration is in the business arena, mainly because of competitive beliefs that cooperation could hurt profitability. We have found such behavior in a wide variety of countries, in advanced and developing economies. Such cultural behaviors or traits characterized entrepreneurs by working in isolation, avoiding the possibilities of building clusters to promote regional development. The needs to improve the essential abilities that conforms cooperation are evident. It is also very difficult to change such conduct with adults. So we decided to work with children to prepare future generations to live in a cooperative world, so badly hit by greed and individualism nowadays. We have validated that working with children at an early age improves such behavior. This paper develops a model to enhance the essential abilities in order to improve cooperation. The model has been validated by applying it at a kindergarten school.

  8. A tribute to Peter A. Rona: A Russian Perspective

    Science.gov (United States)

    Sagalevich, Anatoly; Lutz, Richard A.

    2015-11-01

    In July 1985 Peter Rona led a cruise of the National Oceanic and Atmospheric Administration (NOAA) ship Researcher as part of the NOAA Vents Program and discovered, for the first time, black smokers, massive sulfide deposits and vent biota in the Atlantic Ocean. The site of the venting phenomena was the Trans-Atlantic Geotraverse (TAG) Hydrothermal Field on the east wall of the rift valley of the Mid-Atlantic Ridge at 26°08‧N; 44°50‧W (Rona, 1985; Rona et al., 1986). In 1986, Peter and an international research team carried out multidisciplnary investigations of both active and inactive hydrothermal zones of the TAG field using the R/V Atlantis and DSV Alvin, discovering two new species of shrimp (Rimicaris exoculata and Chorocaris chacei) (Williams and Rona, 1986) and a hexagonal-shaped form (Paleodictyon nodosum) thought to be extinct (Rona et al., 2009). In 1991 a Russian crew aboard the R/V Akademik Mstislav Keldysh, with two deep-diving, human-occupied submersibles (Mir-1 and Mir-2) (Fig. 1), had the honor of having Peter Rona and a Canadian IMAX film crew from the Stephen Low Company on board to visit the TAG hydrothermal vent field. This was the first of many deep-sea interactions between Russian deep-sea scientists and their colleagues from both the U.S. and Canada. This expedition to the TAG site was part of a major Russian undersea program aimed at exploring extreme deep-sea environments; between 1988 and 2005, the Mir submersibles visited hydrothermal vents and cold seep areas in 20 deep-sea regions throughout the world's oceans (Sagalevich, 2002). Images of several of these areas (the TAG, Snake Pit, Lost City and 9°50‧N vent fields) were obtained using an IMAX camera system emplaced for the first time within the spheres of the Mir submersibles and DSV Alvin in conjunction with the filming of science documentaries (e.g., "Volcanoes of the Deep Sea") produced by the Stephen Low Company in conjunction with Emory Kristof of National Geographic and

  9. A Fat strange Repeller

    Institute of Scientific and Technical Information of China (English)

    申影; 何阅; 姜玉梅; 何大韧

    2004-01-01

    This article reports an observation on a fat strange repeller, which appears after a characteristic crisis observed in a kicked rotor subjected to a piecewise continuous force field. The discontinuity border in the definition range of the two-dimensional mapping, which describes the system, oscillates as the discrete time develops. At a threshold of a control parameter a fat chaotic attractor suddenly transfers to a fat transient set. The strange repeller, which appears after the crisis, is also a fat fractal. This is the reason why super-transience happens

  10. Anatomy of a Bounce

    CERN Document Server

    Medved, A J M

    2003-01-01

    Holographic considerations are used in the scrutiny of a special class of brane-world cosmologies. Inherently to this class, the brane typically bounces, at a finite size, as a consequence of a charged black hole in the bulk. Whereas a prior treatment [hep-th/0301010] emphasized a brane that is void of standard-model matter, the analysis is now extended to include an intrinsic (radiation-dominated) matter source. An interesting feature of this generalized model is that a bounce is no longer guaranteed but, rather, depends on the initial conditions. Ultimately, we demonstrate that compliance with an appropriate holographic bound is a sufficient prerequisite for a bounce to occur.

  11. A Causal Rhythm Grouping

    DEFF Research Database (Denmark)

    Jensen, Karl Kristoffer

    2005-01-01

    This paper presents a method to identify segment boundaries in music. The method is based on a multi-step model; first a features is measured from the audio, then a measure of rhythm is calculated from the feature, the diagonal of a self-similarity matrix is calculated, and finally the segment...

  12. A Revamped Science Expo

    Science.gov (United States)

    Barth, Lorna

    2007-01-01

    By changing the venue from festival to a required academic exposition, the traditional science fair was transformed into a "Science Expo" wherein students were guided away from cookbook experiments toward developing a question about their environment into a testable and measurable experiment. The revamped "Science Expo" became a night for students…

  13. What's a Funny Bone?

    Science.gov (United States)

    ... Help White House Lunch Recipes What's a Funny Bone? KidsHealth > For Kids > What's a Funny Bone? Print A A A Text Size Have you ... prickly kind of dull pain? That's your funny bone! It doesn't really hurt as much as ...

  14. Creating a Marketing Plan.

    Science.gov (United States)

    Sevier, Robert A.

    1989-01-01

    A guide to developing a college marketing plan defines key marketing terms, outlines the development of a plan (including institutional analysis, market research, strategy formation and execution, and program evaluation), and provides a list of important principles with which to operate a program. (MSE)

  15. A Height Inequality

    OpenAIRE

    Zha, Yuhan

    2009-01-01

    We give a mathematical structure on an arithmetic surface, that has algebraic meanings over finite places and can estimate the canonical norm for a relative differential form on the arithmetic surface. This will give a lower bound for the canonical norm for a relative differential form on an arithmetic surface, which proves a Height Inequality on the arithmetic surface.

  16. A Night's Sleep, Ultracheap

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ You tote your own luggage, the bed's a bit stiff, and the decor in the spartan rooms and lobby is reminiscent of a college dorm. Oh-and you can't buy a beer. But for $22 a night,the indi One Hotel is one heck of a bargain.

  17. A Video Control Processor

    OpenAIRE

    Tripp, Gerald

    1992-01-01

    This report describes the design and implementation of a simple microprogrammable processor with a fast response time to external events. This processor was designed as a controller for a testbench video system capable of performing a number of functions such as windowing and frame rate conversion.

  18. Chopping a Point

    DEFF Research Database (Denmark)

    Chaochen, Z.; Hansen, Michael Reichhardt

    1996-01-01

    This paper introduces a super-dense chop modality into the Duration Calculi. The super-dense chop can be used to specify a super-dense computation, where a number of operations happens simultaneously, but in a specific order. With this modality, the paper defines a real-time semantics for an OCCA...

  19. Designing a Weather Station

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

  20. Advice to a Rookie

    Science.gov (United States)

    Hudnut, Thomas C.

    1976-01-01

    This article is a brief summary of the method of college advising used at St. Albans. It is in the form of a letter from an "old pro" to a neophyte. The author feels it is a useful checklist for college counselors, particularly those new to the business. It might also serve as a yardstick for experienced counselors who can measure their own…

  1. A Helical Stairway Project

    Science.gov (United States)

    Farmer, Tom

    2008-01-01

    We answer a geometric question that was raised by the carpenter in charge of erecting helical stairs in a 10-story hospital. The explanation involves the equations of lines, planes, and helices in three-dimensional space. A brief version of the question is this: If A and B are points on a cylinder and the line segment AB is projected radially onto…

  2. PREFACE: A Stellar Journey A Stellar Journey

    Science.gov (United States)

    Asplund, M.

    2008-10-01

    The conference A Stellar Journey was held in Uppsala, Sweden, 23 27June 2008, in honour of Professor Bengt Gustafsson's 65th birthday. The choice of Uppsala as the location for this event was obvious given Bengt's long-standing association with the city stemming back to his school days. With the exception of a two-year postdoc stint in Copenhagen, five years as professor at Stockholm University and two years as director of the Sigtuna foundation, Bengt has forged his illustrious professional career at Uppsala University. The symposium venue was Museum Gustavianum, once the main building of the oldest university in Scandinavia. The title of the symposium is a paraphrasing of Bengt's popular astronomy book Kosmisk Resa (in English: Cosmic Journey) written in the early eighties. I think this aptly symbolizes his career that has been an astronomical voyage from near to far, from the distant past to the present. The original book title was modified slightly to reflect that most of his work to date has dealt with stars in one way or another. In addition it also gives credit to Bengt's important role as a guiding light for a very large number of students, colleagues and collaborators, indeed for several generations of astronomers. For me personally, the book Kosmisk Resa bears particular significance as it has shaped my life rather profoundly. Although I had already decided to become an astronomer, when I first read the book as a 14-year-old I made up my mind then and there that I would study under Bengt Gustafsson and work on stars. Indeed I have remained true to this somewhat audacious resolution. I suspect that a great number of us have similar stories how Bengt has had a major influence on our lives, whether on the professional or personal level. Perhaps Bengt's most outstanding characteristic is his enthralling enthusiasm. This is equally true whether he is pondering some scientific conundrum, supervising students or performing in front of an audience, be it an

  3. Eph receptor A10 has a potential as a target for a prostate cancer therapy.

    Science.gov (United States)

    Nagano, Kazuya; Yamashita, Takuya; Inoue, Masaki; Higashisaka, Kazuma; Yoshioka, Yasuo; Abe, Yasuhiro; Mukai, Yohei; Kamada, Haruhiko; Tsutsumi, Yasuo; Tsunoda, Shin-ichi

    2014-07-18

    We recently identified Eph receptor A10 (EphA10) as a novel breast cancer-specific protein. Moreover, we also showed that an in-house developed anti-EphA10 monoclonal antibody (mAb) significantly inhibited proliferation of breast cancer cells, suggesting EphA10 as a promising target for breast cancer therapy. However, the only other known report for EphA10 was its expression in the testis at the mRNA level. Therefore, the potency of EphA10 as a drug target against cancers other than the breast is not known. The expression of EphA10 in a wide variety of cancer cells was studied and the potential of EphA10 as a drug target was evaluated. Screening of EphA10 mRNA expression showed that EphA10 was overexpressed in breast cancer cell lines as well as in prostate and colon cancer cell lines. Thus, we focused on prostate cancers in which EphA10 expression was equivalent to that in breast cancers. As a result, EphA10 expression was clearly shown in clinical prostate tumor tissues as well as in cell lines at the mRNA and protein levels. In order to evaluate the potential of EphA10 as a drug target, we analyzed complement-dependent cytotoxicity effects of anti-EphA10 mAb and found that significant cytotoxicity was mediated by the expression of EphA10. Therefore, the idea was conceived that the overexpression of EphA10 in prostate cancers might have a potential as a target for prostate cancer therapy, and formed the basis for the studies reported here. PMID:24924629

  4. Making a Difference: a Global Geoscience Initiative

    Science.gov (United States)

    Nickless, E.

    2013-05-01

    Since 2009, an informal group, comprising four former board members of the International Year of Planet Earth, has been promoting the concept of a so-called Global Geoscientific Initiative. The GGI should: i.Be inclusive, involve a geoscience community, which is broad both in terms of discipline and nationality, and involve the social sciences; ii.Have a clear socio-economic context and global societal relevance; iii.Focus on a globally significant science theme and preferably involve global processes; iv.Attract the support of geoscientific communities, funding agencies, governments and other institutions in many countries, under the umbrella of UNESCO, ICSU and its geoscientific unions. A series of five town hall meetings have been held at which usually three invited, well-respected figures from the geoscientific community gave presentations. Those presentations were followed by discussion about the importance or otherwise of particular areas of science, and the need to engage better with legislators, policy makers, the media and the lay public. No one challenged the desirability of a large-scale programme that would attract researchers from many geoscientific disciplines and potentially involve the geo-unions. The discussions can be summarised under three broad themes: i.Mineral and hydrocarbon resources and their waste products; ii.Living with natural hazards; iii.Strategic Earth science in Africa through the Africa Alive corridors. During the course of development of the GGI, ICSU has issued a number of papers, most recently a strategic plan, covering the period 2012-2017, working parties have been undertaking foresight analysis and there have also been discussions concerning regional environmental change: human action and adaptation with the question "what does it take to meet the Belmont challenge?". The Belmont Forum brings together a number of funding agencies and could provide the resource to enable some initiative to go forward. More recently a programme

  5. A black hole in a globular cluster.

    Science.gov (United States)

    Maccarone, Thomas J; Kundu, Arunav; Zepf, Stephen E; Rhode, Katherine L

    2007-01-11

    Globular star clusters contain thousands to millions of old stars packed within a region only tens of light years across. Their high stellar densities make it very probable that their member stars will interact or collide. There has accordingly been considerable debate about whether black holes should exist in these star clusters. Some theoretical work suggests that dynamical processes in the densest inner regions of globular clusters may lead to the formation of black holes of approximately 1,000 solar masses. Other numerical simulations instead predict that stellar interactions will eject most or all of the black holes that form in globular clusters. Here we report the X-ray signature of an accreting black hole in a globular cluster associated with the giant elliptical galaxy NGC 4472 (in the Virgo cluster). This object has an X-ray luminosity of about 4 x 10(39) erg s(-1), which rules out any object other than a black hole in such an old stellar population. The X-ray luminosity varies by a factor of seven in a few hours, which excludes the possibility that the object is several neutron stars superposed. PMID:17203062

  6. You are not a gadget a manifesto

    CERN Document Server

    Lanier, Jaron

    2011-01-01

    A programmer, musician, and father of virtual reality technology, Jaron Lanier was a pioneer in digital media, and among the first to predict the revolutionary changes it would bring to our commerce and culture. Now, with the Web influencing virtually every aspect of our lives, he offers this provocative critique of how digital design is shaping society, for better and for worse. Informed by Lanier’s experience and expertise as a computer scientist, You Are Not a Gadget discusses the technical and cultural problems that have unwittingly risen from programming choices—such as the nature of user identity—that were “locked-in” at the birth of digital media and considers what a future based on current design philosophies will bring. With the proliferation of social networks, cloud-based data storage systems, and Web 2.0 designs that elevate the “wisdom” of mobs and computer algorithms over the intelligence and wisdom of individuals, his message has never been more urgent.

  7. Use a defibrillator, save a life

    CERN Multimedia

    Joannah Caborn Wengler

    2012-01-01

    With the work for Long Shutdown 1 looming on the horizon, the CERN Fire Brigade is anticipating a heavy workload: more people working at CERN means more call-outs. So the more trained first-aiders around to help out before the paramedics arrive, the better. Would you know what to do in a medical emergency?   It could happen at any time: two colleagues are having a coffee at work, when one suddenly clutches his or her chest and falls to the floor unconscious. What would you do? Run to find a first-aider? Call the ambulance and wait, finishing your coffee? Neither response is entirely correct. On Monday 11 June in Building 40 the CMS safety group, in collaboration with the Fire Brigade and the Medical Service, demonstrated the recommended, potentially life-saving response to cardiac arrest (see the video), including the correct use of a defibrillator, ten of which were recently installed in key CERN locations (the Bulletin reported).     “In countries where...

  8. A metastatic colorectal carcinoma: A curative approach?

    Directory of Open Access Journals (Sweden)

    Basara Nadezda

    2014-01-01

    Full Text Available Background: Unresectable colorectal liver metastases can be resected after response to chemotherapy. The use of neoadjuvant chemotherapy with or without targeted monoclonal antibodies increases the proportion of resectable liver metastasis and conferred a long term survival of 40%. Methods: The current ongoing studies regarding neodjuvant treatment strategies aiming to increase a proportion of patients with resectable liver metastases is going to be presented. Results: Perioperative chemotherapy with FOLFOX4 is compatible with major liver surgery and reduces the risk of events of progression free survival in resected patients. The results of the CELIM study confirm a favourable long-term survival for patients with initially suboptimal or unresectable colorectal liver metastasis who respond to conversion therapy and undergo secondary resection. The New EPOC randomised trial does not support the addition of cetuximab to chemotherapy and surgery for operable colorectal liver metastasis in KRAS exon 2 wild-type patients. Conclusion: The ability of anti-epidermal growth factor receptor agents to increase response rate and resection when added to chemotherapy has been clearly shown in a number of trials. The resection rates are higher with chemotherapy plus Cetuximab, in general, a conversion is contributes to the better overall survival.

  9. A costal dispersion model

    International Nuclear Information System (INIS)

    A dispersion model to be used off costal waters has been developed. The model has been applied to describe the migration of radionuclides in the Baltic sea. A summary of the results is presented here. (K.A.E)

  10. Mucopolysaccharidosis: A New Variant?

    Science.gov (United States)

    Primrose, D. A.

    1972-01-01

    Described is a possibly new variant of mucopolysaccharidosis characterized by progressive mental and motor deficiency, bone abnormalities, a generalized skin lesion, and abnormal mucopolysaccharides in the urine as seen in a 20-year-old female. (DB)

  11. Using a cane

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000343.htm Using a cane To use the sharing features on this page, ... a walker may be better options for you. Cane Basics The most common question about using a ...

  12. A major safety overhaul

    CERN Document Server

    2003-01-01

    A redefined policy, a revamped safety course, an environmental project... the TIS (Technical Inspection and Safety) Division has begun a major safety overhaul. Its new head, Wolfgang Weingarten, explains to the Bulletin why and how this is happening.

  13. A Simple Calculator Algorithm.

    Science.gov (United States)

    Cook, Lyle; McWilliam, James

    1983-01-01

    The problem of finding cube roots when limited to a calculator with only square root capability is discussed. An algorithm is demonstrated and explained which should always produce a good approximation within a few iterations. (MP)

  14. Building a Better Planet

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Transitioning into a broader role as senior civil servant of the United Nations after 37 years as a Chinese diplomat,UN Under Secretary General Sha Zukang certainly has had a tough task to quickly understand UN culture

  15. What Is a Colonoscopy

    Medline Plus

    Full Text Available ... cancer from forming. So, we have become a standard. We are in a beautiful suite at Broward ... less than 1 mm. We have the high definition colonoscope by Olympus. This also has a filter ...

  16. A smattering of antimatter.

    CERN Multimedia

    Yam, P

    1996-01-01

    Physicists at CERN have succeeded in developing antihydrogen by directing a beam of antiprotons through a jet of xenon atoms. The antihydrogen results from the interaction of one antiproton with a xenon atom. However, it lasts for only 40 seconds.

  17. Checking a printed board

    CERN Multimedia

    1977-01-01

    An 'Interactive Printed Circuit Board Design System' has been developed by a company in a Member-State. Printed circuits are now produced at the SB's surface treatment workshop using a digitized photo-plotter.

  18. Vitamin A blood test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003570.htm Vitamin A blood test To use the sharing features on this page, please enable JavaScript. The vitamin A test measures the level of vitamin A ...

  19. Preventing hepatitis A

    Science.gov (United States)

    ... are available to protect against hepatitis A infection. Hepatitis A vaccination is recommended for all children older than age ... Saunders; 2016:chap 148. Sjogren MH, Bassett JT. Hepatitis A. In: ... Practices (ACIP); ACIP Child/Adolescent Immunization Work Group. ...

  20. Gardening from a Wheelchair

    Science.gov (United States)

    ... Paralysis > Health > Staying active > Gardening from a wheelchair Gardening from a wheelchair ☷ ▾ Page contents Tips from community ... round handles) on gate latches, doors, and faucets. Gardening as therapy For Gene Rothert gardening is a ...

  1. What's a Halo?

    Science.gov (United States)

    ... Delight: Melon Smoothie Pregnant? Your Baby's Growth What's a Halo? KidsHealth > For Parents > What's a Halo? Print ... confined to bed rest while they recover. What's a Halo? The halo gets its name from the ...

  2. Preventing hepatitis A

    Science.gov (United States)

    Hepatitis A is inflammation (irritation and swelling) of the liver caused by the hepatitis A virus. You can take several steps to ... reduce your risk of spreading or catching the hepatitis A virus: Always wash your hands thoroughly after ...

  3. A Czech Morphological Lexicon

    OpenAIRE

    Skoumalova, Hana

    1997-01-01

    In this paper, a treatment of Czech phonological rules in two-level morphology approach is described. First the possible phonological alternations in Czech are listed and then their treatment in a practical application of a Czech morphological lexicon.

  4. Herbs at a Glance

    Science.gov (United States)

    ... Events Multimedia (Video, Images, and Audio) NCCIH Clinical Digest A monthly newsletter with evidence-based information on ... desktop. If you have a Kindle device or reader, you can add a new eBook to your ...

  5. A vircator amplifier

    International Nuclear Information System (INIS)

    A cavity vircator has demonstrated that formation of a virtual cathode in a cavity can improve microwave production efficiency and narrow the radiation bandwidth. When the virtual cathode radiates the microwave fields grow from noise. For each cavity, there is only one or a limited number of allowable modes for a given frequency. In this paper, a novel device - a vircator amplifier is described. The device consists of a relativistic magnetron and a cavity vircator with both devices powered by a 1 MeV, 3 Ω, 65 ns FWHM pulser. The idea is to inject a signal from the magnetron before and during virtual cathode formation in a cavity. The injected signal should lock the frequency and enhance electron bunching and therefore improve efficiency further. Experiments underway to evaluate the amplifier operating characteristics are discussed. The applicability of vircator amplifiers to the next generation of high-power microwave devices are addressed

  6. Medullomyoblastoma : A case report.

    OpenAIRE

    ArunKumar M; Chacko G; Chandi S; Chandy M

    1999-01-01

    Medullomyoblastoma is a rare tumour seen in childhood. We report a medullomyoblastoma occurring in the cerebellar vermis of a 4 year old boy. The light microscopic features, immunohistochemistry and histogenesis are described.

  7. A Call for Justice

    OpenAIRE

    Marques-Silva, Joao; Brahmachari, Debahuti; Sakallah, Karem; Lynce, Ines

    2015-01-01

    Abstract A new development can be identified within the civil society in Malaysia. A development that has resulted in a general call for justice, voiced through coalition groups that cut across categories of affiliation. This development is triggered by an increasing inculcation of Islamic values into the political system, which has interfered with the understanding of Malaysia as a country that can provide a framework for coexistence within a multicultural society. This thesis seeks ...

  8. A Magnetic Wormhole

    OpenAIRE

    Jordi Prat-Camps; Carles Navau; Alvaro Sanchez

    2015-01-01

    Wormholes are fascinating cosmological objects that can connect two distant regions of the universe. Because of their intriguing nature, constructing a wormhole in a lab seems a formidable task. A theoretical proposal by Greenleaf et al. presented a strategy to build a wormhole for electromagnetic waves. Based on metamaterials, it could allow electromagnetic wave propagation between two points in space through an invisible tunnel. However, an actual realization has not been possible until now...

  9. Differentiating Ambiguity: A Comment.

    OpenAIRE

    Jurgen Eichberger; Simon Grant; David Kelsey

    2006-01-01

    In Ghirardato, Macheroni and MArcinaccri (GMM) propose a method for distinguishing between percieved ambiguity and the decision-maker's reaction to it. They study a general class of preferences which includes CEU and a-MEU and axiomatise a subclass of a-MEU preferences. We show that for Hurwicz preferences the proposed measure of ambiguity depends on parameters which intuitively reflect ambiguity-attitude. Furthermore, any a-MEU preferences which satisfy the CEU axioms, satisfy GMM's axioms i...

  10. Buying a New Car?

    Institute of Scientific and Technical Information of China (English)

    Paul; Maghielse

    2000-01-01

    You read it here first, folks: a car buying processthat first counsels its readers not to buy a car! Why?Because, no matter what mystical incantations a carsalesperson may whisper in your ear, cars are notinvestments. Certainly, there are a few exceptions to that rule,but in general. vehicles are what the accountantsamong us call depreciating assets. Think of a vehiclepurchase in comparison with the other big-ticketpurchases we make during our lifetimes. Buying a

  11. A Workshop that Works

    OpenAIRE

    Yunes, Nicolas; Key, Joey Shapiro

    2014-01-01

    The main goal of a scientific workshop is to bring together experts in a specific field or related fields to collaborate, to discuss, and to creatively make progress in a particular area. The organizational aspects of such a meeting play a critical role in achieving these goals. We here present suggestions from scientists to scientists that hopefully help in organizing a successful scientific workshop that maximizes collaboration and creativity.

  12. 'A Place to Sit'

    DEFF Research Database (Denmark)

    Hvejsel, Marie Frier; Klok, Julie Skovgaard; Bøhnke, Mia Marker

    Published in 2014 on the occasion of the third 'A Place to Sit' exhibition as a reflection upon three years of teaching tectonic method in architecture using the furniture scale as a learning basis.......Published in 2014 on the occasion of the third 'A Place to Sit' exhibition as a reflection upon three years of teaching tectonic method in architecture using the furniture scale as a learning basis....

  13. A Beautiful Spin

    International Nuclear Information System (INIS)

    Spin is a beautiful concept that plays an ever important role in modern physics. In this talk, I start with a discussion of the origin of spin, and then turn to three themes in which spin has been crucial in subatomic physics: a lab to explore physics beyond the standard model, a tool to measure physical observables that are hard to obtain otherwise, a probe to unravel nonperturbative QCD. I conclude with some remarks on a world without spin

  14. Building a professional portfolio.

    OpenAIRE

    Arhippainen, Mikko

    2016-01-01

    Building a professional portfolio is a thesis report with buiding a professional portfolio for the author with a background in graphic design and event management with main interest on aesthetics side. This report describes the main process of selecting materials, planning and actually producing the portfolio. In addition to the portfolio there is a chapter with inspection on LinkedIn and other social medias when planning for jobsearch. Altogether it is many channels and a combination of ...

  15. A sound sleep

    OpenAIRE

    Rudra Prosad Goswami; Swati Mondal; Subrata Basu; Partha Sarathi Karmakar; Alakendu Ghosh

    2012-01-01

    Benzodiazepine is a commonly encountered agent of poisoning, which is readily diagnosed by a pertinent history of drug ingestion and the clinical scenario. In the absence of a proper drug history, the diagnosis becomes challenging. Proper clinical assessment, urine assays and imaging play a very important role in reaching the diagnosis. We present a case of acute benzodiazepine poisoning without a history of drug intake. The key pointers toward diagnosis were an unarousable state with obstruc...

  16. Pop in a Popper

    Science.gov (United States)

    Reading Teacher, 2011

    2011-01-01

    This article describes Pop in a Popper, an effective lesson for teaching students how to choose and use words to give their writing fluency and flair. Pop in a Popper introduces the appositive: a group of words inserted after a noun to modify that noun. In simplest terms, writers pop this group of words into a sentence to tell more about a noun.…

  17. Gamification as a Service

    OpenAIRE

    Herzig, Philipp

    2014-01-01

    Gamification is a novel method to improve engagement, motivation, or participation in non-game contexts using game mechanics. To a large extent, gamification is a psychological- and design-oriented discipline, i.e., a lot of effort has to be spent already in the design phase of a gamification project. Subsequently, the design is implemented in information systems such as portals or enterprise resource planning applications. These systems act as mediators to transport a gameful design to its u...

  18. A power measuring device

    International Nuclear Information System (INIS)

    As a part of the klystron test facility of the Dutch NIKHEF-K accelerator, a sensitive power measuring device has been built. The high-frequency power of a klystron is stored in a water-cooled dummy load. Using a microcomputer, the increase of the water temperature and the water flow rate are transformed to a digital indication of the klystron power. (Auth.)

  19. Packing a cake into a box

    KAUST Repository

    Skopenkov, Mikhail

    2011-05-01

    Given a triangular cake and a box in the shape of its mirror image, how can the cake be cut into a minimal number of pieces so that it can be put into the box? The cake has icing, so we are not allowed to put it into the box upside down. V. G. Boltyansky asked this question in 1977 and showed that three pieces always suffice. In this paper we provide examples of cakes that cannot be cut into two pieces to be put into the box. This shows that three is the answer to Boltyansky\\'s question. We also give examples of cakes which can be cut into two pieces. © THE MATHEMATICAL ASSOCIATION OF AMERICA.

  20. A kinematic model of a solar flare.

    Science.gov (United States)

    Nakagawa, Y.; Wu, S. T.; Han, S. M.

    1973-01-01

    Hyder advocated the idea that the optical (H-alpha) flares can be identified with the response of the solar chromosphere to an infalling material stream resulting from the 'disparition brusque' of a prominence. Since some flares are observed without any apparent association with infalling streams, in this paper we examine the possibility of identifying the optical flare with the response of the chromosphere to a supersonic disturbance, i.e., a shock, propagating downward. The undisturbed chromosphere is represented by the Harvard-Smithsonian Reference Atmosphere and the evolution of the shock is evaluated with the use of the CCW (Chisnell, Chester, Whitham) approximation based on the theory of characteristics. It is shown that the chromosphere is heated by the shock, that radiation is enhanced, and that the enhanced radiation terminates the shock around the height of the temperature minimum.

  1. A sun holiday is a sunburn holiday

    DEFF Research Database (Denmark)

    Petersen, Bibi; Thieden, Elisabeth; Philipsen, Peter Alshede;

    2013-01-01

    percentage of body surface area with sunburn. Our study shows that holiday UVR exposure results in a high risk of sunburn, which potentially increases the risk of skin cancer. Possible protection by melanogenesis is insufficient to protect against sunburn during a 1-week sun holiday. Finally, our data...... by daily skin examinations by the same observer. Erythemally effective ultraviolet radiation (UVR) exposure was assessed with time-stamped personal dosimeters worn on the wrist. Volunteers reported their clothing cover and sunscreen use in diaries, and this information was used to determine body site......-specific UVR doses after adjustment for sun protection factor. Remarkably, we found that all volunteers sunburned at some point. The risk of sunburn correlated significantly with the adjusted body site-specific UVR dose. Furthermore, there was also a significant relationship between the daily UVR dose and...

  2. A plunger for a plunger lift

    Energy Technology Data Exchange (ETDEWEB)

    Abdulaadze, A.M.G.; Abdulzade, R.A.; Amiraslanov, Z.G.; Boboshko, A.V.; Spivak, A.I.

    1984-01-01

    The invention deals with equipment for removing accumulations of water on the bottom hole from gas wells. The purpose of the invention is to increase operational reliability by increasing its sealing capability. The stated purpose is achieved by the fact that in the plunger for the plunger lift, which contains a hollow cylindrical body with radial channels, on the exterior surface of which there is a sealing element, the body is made in the form of two telescopically installed, spring loaded parts which form a hermetically sealed chamber filled with gas with the sealing element, while the sealing element is rigidly linked with the parts of the body. The savings from the introduction of the invention is due to the increase in the reliability and the length of operation of the plunger lift.

  3. A Crypto-Steganography: A Survey

    Directory of Open Access Journals (Sweden)

    Md. Khalid Imam Rahmani

    2014-08-01

    Full Text Available The two important aspects of security that deal with transmitting information or data over some medium like Internet are steganography and cryptography. Steganography deals with hiding the presence of a message and cryptography deals with hiding the contents of a message. Both of them are used to ensure security. But none of them can simply fulfill the basic requirements of security i.e. the features such as robustness, undetectability and capacity etc. So a new method based on the combination of both cryptography and steganography known as Crypto-Steganography which overcome each other’s weaknesses and make difficult for the intruders to attack or steal sensitive information is being proposed. This paper also describes the basics concepts of steganography and cryptography on the basis of previous literatures available on the topic.

  4. Rehabilitating a brain with Alzheimer's: a proposal

    Directory of Open Access Journals (Sweden)

    Gonzalo Emiliano Aranda-Abreu

    2011-02-01

    Full Text Available Gonzalo Emiliano Aranda-Abreu1,3, María Elena Hernández-Aguilar1,3, Jorge Manzo Denes1,4, Luis Isauro García Hernández1,4, Marisol Herrera Rivero21Programa de Neurobiología, 2Doctorado en Ciencias Biomédicas, Universidad Veracruzana, Xalapa, Veracruz, México, 3Cuerpo Académico de Neuroquímica, 4Cuerpo Académico de Neurociencias.Abstract: Alzheimer's disease (AD is the most common neurodegenerative disorder, originating sporadically in the population aged over 65 years, and advanced age is the principal risk factor leading to AD development. In spite of the large amount of research going on around the globe and all the information now available about AD, there is still no origin or triggering process known so far. Drugs approved for the treatment of AD include tacrine, donepezil, rivastigmine, galantamine, and memantine. These may delay or slow down the degenerative process for a while, but they can neither stop nor reverse its progression. Because that this might be due to a lack of effect of these drugs on degenerating neurons, even when they are able to potentiate the brain in nondegenerative conditions, we propose here an alternative therapy consisting of initial repair of neuronal membranes followed by conventional drug therapies. The rehabilitation of neurons in a degeneration process would enable the drugs to act more effectively on them and improve the effects of treatment in AD patients.Keywords: Alzheimer, Rehabilitation, Drugs

  5. Melatonin as a radioprotective agent: a review

    International Nuclear Information System (INIS)

    Melatonin (N-acetyl-5-methoxytryptamine), the chief secretory product of the pineal gland in the brain, is well known for its functional versatility. In hundreds of investigations, melatonin has been documented as a direct free radical scavenger and an indirect antioxidant, as well as an important immunomodulatory agent. The radical scavenging ability of melatonin is believed to work via electron donation to detoxify a variety of reactive oxygen and nitrogen species, including the highly toxic hydroxyl radical. It has long been recognized that the damaging effects of ionizing radiation are brought about by both direct and indirect mechanisms. The direct action produces disruption of sensitive molecules in the cells, whereas the indirect effects (∼70%) result from its interaction with water molecules, which results in the production of highly reactive free radicals such as ·OH, ·H, and eaq- and their subsequent action on subcellular structures. The hydroxyl radical scavenging ability of melatonin was used as a rationale to determine its radioprotective efficiency. Indeed, the results from many in vitro and in vivo investigations have confirmed that melatonin protects mammalian cells from the toxic effects of ionizing radiation. Furthermore, several clinical reports indicate that melatonin administration, either alone or in combination with traditional radiotherapy, results in a favorable efficacy:toxicity ratio during the treatment of human cancers. This article reviews the literature from laboratory investigations that document the ability of melatonin to scavenge a variety of free radicals (including the hydroxyl radical induced by ionizing radiation) and summarizes the evidence that should be used to design larger translational research-based clinical trials using melatonin as a radioprotector and also in cancer radiotherapy. The potential use of melatonin for protecting individuals from radiation terrorism is also considered

  6. A rare case of a transabdominal impalement after a fall from a ladder

    Directory of Open Access Journals (Sweden)

    Angelopoulos Stamatios

    2016-01-01

    Conclusion: The article describes a case of a transabdominal impalement injury and pinpoints the strategies followed regarding the prehospital care, as well as the intra- and postoperative management.

  7. A Study on a Software Quality Assurance of a Process and a Product

    International Nuclear Information System (INIS)

    Since nuclear plants and facilities have made increasing use of digital technology, the safety and reliability of software is a primary concern. Software errors are more difficult to detect and handle than hardware-related failures. It is crucial to consider the a process and a product of a software life cycle to increase the quality of a software. This paper discusses the quality assurance of a process and a product of a software life cycle based on two prominent standards, ISO 9001:2000 and CMMI

  8. What Is a Constitution?

    Science.gov (United States)

    OAH Magazine of History, 1988

    1988-01-01

    Provides a lesson plan designed to help students better understand the concept of a constitution, distinguish constitutional law from statutory law, and recognize examples of constitutional government. (BSR)

  9. A versatile electrostatic trap

    CERN Document Server

    van Veldhoven, J; Meijer, G; Schnell, M; Bethlem, Hendrick L.; Meijer, Gerard; Schnell, Melanie; Veldhoven, Jacqueline van

    2006-01-01

    A four electrode electrostatic trap geometry is demonstrated that can be used to combine a dipole, quadrupole and hexapole field. A cold packet of 15ND3 molecules is confined in both a purely quadrupolar and hexapolar trapping field and additionally, a dipole field is added to a hexapole field to create either a double-well or a donut-shaped trapping field. The profile of the 15ND3 packet in each of these four trapping potentials is measured, and the dependence of the well-separation and barrier height of the double-well and donut potential on the hexapole and dipole term are discussed.

  10. Between a Map and a Data Rod

    Science.gov (United States)

    Teng, W. L.; Rui, H.; Strub, R. F.; Vollmer, B.

    2015-12-01

    A "Digital Divide" has long stood between how NASA and other satellite-derived data are typically archived (time-step arrays or "maps") and how hydrology and other point-time series oriented communities prefer to access those data. In essence, the desired method of data access is orthogonal to the way the data are archived. Our approach to bridging the Divide is part of a larger NASA-supported "data rods" project to enhance access to and use of NASA and other data by the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) Hydrologic Information System (HIS) and the larger hydrology community. Our main objective was to determine a way to reorganize data that is optimal for these communities. Two related objectives were to optimally reorganize data in a way that (1) is operational and fits in and leverages the existing Goddard Earth Sciences Data and Information Services Center (GES DISC) operational environment and (2) addresses the scaling up of data sets available as time series from those archived at the GES DISC to potentially include those from other Earth Observing System Data and Information System (EOSDIS) data archives. Through several prototype efforts and lessons learned, we arrived at a non-database solution that satisfied our objectives/constraints. We describe, in this presentation, how we implemented the operational production of pre-generated data rods and, considering the tradeoffs between length of time series (or number of time steps), resources needed, and performance, how we implemented the operational production of on-the-fly ("virtual") data rods. For the virtual data rods, we leveraged a number of existing resources, including the NASA Giovanni Cache and NetCDF Operators (NCO) and used data cubes processed in parallel. Our current benchmark performance for virtual generation of data rods is about a year's worth of time series for hourly data (~9,000 time steps) in ~90 seconds. Our approach is a specific

  11. A heating partition for a coking furnace

    Energy Technology Data Exchange (ETDEWEB)

    Strelov, K.K.; Ivanova, A.V.; Kaufman, A.A.; Kuznetsov, G.I.; Likhogub, Ye.P.; Turman, D.S.; Varshavskiy, T.P.; Volfovskiy, G.M.

    1983-01-01

    A coking furnace heating partition (OPKT) is proposed in order to increase reliability by increasing its strength. The proposal includes equipping with a vertical wall (St) made of Dinas brick and positioning it along the longitudinal axis of the coking furnace heating panel. The dividing walls are made of Dinas brick and their faces are disposed between the bricks of the wall of the coking chamber (KK). The surface of the coking chamber wall is made from magnesite or corundum brick which makes up 70 to 80 percent of the operational surface (Pv) of the wall. The presence of the vertical wall in combination with the

  12. Electricity - a gateway to a better environment

    International Nuclear Information System (INIS)

    It is shown that the use and production of electricity in the domains of building heating, industrial processes and transportation, in terms of emissions into the atmosphere may be environmentally more advantageous than the local use of other types of energy. This applies particularly to the Swedish electricity production system (mainly hydro and nuclear power) but is also demonstrated that the use of electricity from modern power plants based on a natural gas combined cycle (NGCC) or coal-fired condensing plant with a high standard of treatment can compete environmentally in several respects with the local use of oil. 7 figs., 1 tab

  13. Diaspora: A Look Back on a Concept

    Directory of Open Access Journals (Sweden)

    William Berthomière

    2007-10-01

    Full Text Available There are some words that are used at loosing theirs meanings. Diaspora is one of these. Full or empty of meaning, we are speaking today of “Cultural Diasporas” (Cohen, of “Fear Diasporas” (Appaduraï, of “Virtual Diasporas,” etc. This introductive paper is an attempt to clarify the development of a concept since the beginning of its life inside the Social Sciences during the 70’s. The term diaspora finds its roots in the Greek language and is based on a translation of the Hebrew word, Galut...

  14. Death ends a life, not a relationship

    DEFF Research Database (Denmark)

    Christensen, Dorthe Refslund; Sandvik, Kjetil

    2014-01-01

    In the final chapter, “Death Ends a Life, not a Relationship: objects as media on children’s graves”, Dorthe Refslund Christensen and Kjetil Sandvik investigate the relational affordances offered by objects as media in practices of death and commemoration on children’s graves. The authors argue...... that when it comes to bereavement practices as they materialize on children’s graves, it is the accommodation and decoration of the grave itself that function as media with their variety of physical objects as ritual and relational tools for communication. The bereaved perform practices on children’s...

  15. A Higgs or Not a Higgs?

    CERN Document Server

    Burgess, C P; Pospelov, M E

    2001-01-01

    This talk summarizes a method for analyzing the properties of any new scalar particle, which is systematic in the sense that it minimizes apriori theoretical assumptions about the properties of the scalar particle, leading to very model-independent results. This kind of analysis lends itself to systematic survey through the terrain of candidate theories, which we find has vast unpopulated areas. It is also useful for quantifying the comparison of the goodness of fit of competing descriptions of data, should a new scalar be found.

  16. A conversation with Ralph A. Bradley

    OpenAIRE

    Hollander, Myles

    2001-01-01

    Ralph A. Bradley was born in Smith Falls, Ontario, Canada on Nvember 28, 1923, but grew up in the village of Wellington on the shores of Lake Ontario. He graduated from Queen’s University in 1944 with an honors degree in mathematics and physics, was in the Canadian Army, 1944–1945 and returned to Queen's to complete an M.A. degree in 1946. In 1946 he entered the then new doctoral program in theoretical statistics at the University of Nrth Carolina and received the Ph.D. degr...

  17. What a Difference a Swath Makes!

    Science.gov (United States)

    Mayer, L. A.; Gardner, J. V.

    2014-12-01

    Since the introduction to the academic community of multibeam sonar swath mapping techniques in the late 1970s, the ability to collect high-resolution bathymetry and seafloor imagery has steadily increased. Early systems provided a limited number (e.g., 16) of relatively broad (2-4 degree) beams and swath widths of approximately one times the water depth, whereas current systems offer hundreds of narrower (0.5 to 1 degree) beams over swath widths of five to seven times water depth. Innovations like chirped pulses and high-density beam forming (multiple depth solutions per beam footprint) have also pushed the resolution of modern systems. Despite these improvements, the resolution achievable is fundamentally limited by trade-offs between beam width, bandwidth, transducer size and propagation, resulting in the need for short ranges to the seafloor to achieve the highest levels of resolution. In the deep sea this means delivery of high-frequency, high-resolution mapping systems close to the bottom by means of towed or autonomous vehicles, the trade-off here being limited areal coverage due to narrow swaths and slow mapping speeds. Despite these constraints, we cannot forget that only a small fraction of the deep ocean has been mapped by any sort of swath mapping system (10-20%) and that even a single well-calibrated and properly operated multibeam swath collected at high-speed during a long transit can offer a remarkable amount of insight into seafloor processes. We will illustrate this through the exploration of a single transit by the R/V KILO MOANA (using a Kongsberg EM120 MBES) from Hawaii to Kodiak Alaska. When compared to the best available global bathymetric compilations using both satellite derived bathymetry and existing bathymetric data (e.g., Global Topography of Smith and Sandwell, GMRT, or ETOPO-1), the single swath offers detailed views of deep-sea channels, seamount and guyots, tectonic structure and volcanic processes that are totally absent in the

  18. A Study of a Mechanical Swimming Dolphin

    Science.gov (United States)

    Fang, Lilly; Maass, Daniel; Leftwich, Megan; Smits, Alexander

    2007-11-01

    A one-third scale dolphin model was constructed to investigate dolphin swimming hydrodynamics. Design and construction of the model were achieved using body coordinate data from the common dolphin (Delphinus delphis) to ensure geometric similarity. The front two-thirds of the model are rigid and stationary, while an external mechanism drives the rear third. This motion mimics the kinematics of dolphin swimming. Planar laser induced florescence (PLIF) and particle image velocimetry (PIV) are used to study the hydrodynamics of the wake and to develop a vortex skeleton model.

  19. A Renaissance Depiction of a Tornado.

    Science.gov (United States)

    Hoinka, Klaus P.; de Castro, Manuel

    2005-04-01

    In the Renaissance, impressive weather features inspired considerable interest among artists. The depiction of a tornado and other weather features are discussed that appear on a sixteenth-century series of 12 huge tapestries (“Conquest of Tunis”) woven by the carpet manufacturer Willem de Pannemaker in Brussels, Belgium, between 1549 and 1551. The outstanding depiction of the tornado is presumably the earliest pictorial presentation of a tornado, at least in the Latin west.During the Renaissance, tapestries were an obligatory fixture of a European court and were used as an instrument for political propaganda and dynastic demonstration. The “Conquest of Tunis” tapestries are important pieces of Eu-ropean art commissioned by the Habsburgian emperor Charles V (1500–58), one of the most important ruling personalities in Euro-pean history. In 1535, he undertook a crusade to Tunis, Tunisia, in order to diminish the Ottoman emperor's power in the western Mediterranean region. Charles V wanted to ensure that the expedition would not be forgotten. In order to guarantee this, the emperor took along the Flemish painter Jan Cornelisz Vermeyen who painted sketches that were used as prototypes for the “Conquest of Tunis” tapestries. These present a highly detailed narrative of the expedition to Tunis.The depiction of a tornado, along with heavy rain and a sandstorm, raises the question of why these meteorological features are included in the scene. To the authors' knowledge, no mention is made of them in the art literature (except for the sandstorm, which actually occurred). This is particularly surprising because the tornado, at least, appears so prominently in one of the tapestries. Therefore, the weather features are discussed in terms of their meteorological, decorative, and symbolic importance. The tornado and the heavy rain seem to have been rendered in order to emphasize symbolically the beginning and ending of the military campaign. Although these weather

  20. A vision for a continental energy strategy

    International Nuclear Information System (INIS)

    This paper presented a vision with respect to a continental energy strategy and the principles and goals that must underlie such a strategy. These principles include relying on signals emanating from energy markets to guide investment; limiting the role of government to that of ensuring that the policy and institutional framework is conducive to the development and operation of competitive and innovative energy markets; and ensuring free and open energy trade in energy commodities, both within the continent and with the rest of the world. The paper also identified a number of important factors that, would shape and condition continental energy development and trade. The paper provided an overview of the North American energy use and supply situation for the following resources: oil; natural gas; electricity; coal; nuclear power; hydroelectricity; geothermal energy; wind power; solar power; and ethanol. It also discussed the contribution of the North American Free Trade Agreement (NAFTA) through increased natural gas exports. It was concluded that given the petroleum resources of the three countries and their increased value because of higher oil and gas prices, there was considerable incentive for Canada, the United States, and Mexico to streamline regulations in order to facilitate the efficient development, transportation, and use of the continent's energy resources in accordance with market conditions. 38 refs., 2 tabs., 21 figs