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Sample records for antimycin a

  1. Laboratory studies on antimycin A as a fish toxicant

    Science.gov (United States)

    Berger, Bernard L.; Lennon, Robert E.; Hogan, James W.

    1969-01-01

    Liquid and sand formulations of antimycin A were tested in laboratory waters of various temperature, hardness, pH, and turbidity against 31 species of fresh-water fish of various sizes and life stages. Each formulation of toxicant was lethal under all water conditions to fish eggs, fry, fingerlings, and adult fish. Trouts are the most sensitive and catfishes the least sensitive. Of the 31 species, 24 succumb to 5 p.p.b. or less of the toxicant; only certain catfishes survive 25 p.p.b, The order of toxicity to various species of fish suggests that antimycin has possibilities for selective or partial control of certain unwanted fish. Although toxic to fish under ice, antimycin is more active in warm water than in cold. It is slightly more active in soft water than in hard; it is more active and persists far longer in water at pH 5 to 8 than at pH 9 or 10. It is active on fish in either clear and turbid waters, and it can be detoxified by potassium permanganate, The results contributed to registration of antimycin A in Fintrol-5 formulation as a fish toxicant.

  2. Regulation of antimycin biosynthesis by the orphan ECF RNA polymerase sigma factor σAntA

    Directory of Open Access Journals (Sweden)

    Ryan F. Seipke

    2014-02-01

    Full Text Available Antimycins are an extended family of depsipeptides that are made by filamentous actinomycete bacteria and were first isolated more than 60 years ago. Recently, antimycins have attracted renewed interest because of their activities against the anti-apoptotic machineries inside human cells which could make them promising anti-cancer compounds. The biosynthetic pathway for antimycins was recently characterised but very little is known about the organisation and regulation of the antimycin (ant gene cluster. Here we report that the ant gene cluster in Streptomyces albus is organized into four transcriptional units; the antBA, antCDE, antGF and antHIJKLMNO operons. Unusually for secondary metabolite clusters, the antG and antH promoters are regulated by an extracytoplasmic function (ECF RNA polymerase sigma factor named σAntA which represents a new sub-family of ECF σ factors that is only found in antimycin producing strains. We show that σAntA controls production of the unusual precursor 3-aminosalicylate which is absolutely required for the production of antimycins. σAntA is highly conserved in antimycin producing strains and the −10 and −35 elements at the σAntA regulated antG and antH promoters are also highly conserved suggesting a common mechanism of regulation. We also demonstrate that altering the C-terminal Ala-Ala residues found in all σAntA proteins to Asp-Asp increases expression of the antFG and antGHIJKLMNO operons and we speculate that this Ala-Ala motif may be a signal for the protease ClpXP.

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

    Directory of Open Access Journals (Sweden)

    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.

  4. 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. Copyright © 2011 John Wiley & Sons, Ltd.

  5. The regulation and biosynthesis of antimycins

    Directory of Open Access Journals (Sweden)

    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.

  6. 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.

  7. Binding of the respiratory chain inhibitor antimycin to the mitochondrial bc1 complex: a new crystal structure reveals an altered intramolecular hydrogen-bonding pattern.

    Science.gov (United States)

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

    2005-08-19

    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 2.28 A 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 cytochrome 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 alphaA helix.

  8. 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.

  9. 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...

  10. Open reading frame ssr2016 is required for antimycin A-sensitive photosystem I-driven cyclic electron flow in the cyanobacterium Synechocystis sp. PCC 6803

    NARCIS (Netherlands)

    Yeremenko, Nataliya; Jeanjean, Robert; Prommeenate, Peerada; Krasikov, Vladimir; Nixon, Peter J.; Vermaas, Wim F. J.; Havaux, Michel; Matthijs, Hans C. P.

    2005-01-01

    Open reading frame ssr2016 encodes a protein with substantial sequence similarities to PGR5 identified as a component of the antimycin A-sensitive ferredoxin:plastoquinone reductase (FQR) in PSI cyclic photophosphorylation in Arabidopsis thaliana. We studied cyclic electron flow in Synechocystis sp.

  11. 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.

  12. Anti-apoptotic effects of pan-caspase inhibitor (Z-VAD), SOD or catalase on antimycin A-induced HeLa cell death.

    Science.gov (United States)

    Han, Yong Hwan; Kim, Suhn Hee; Kim, Sung Zoo; Park, Woo Hyun

    2009-01-01

    Antimycin A (AMA) is an inhibitor of the electron transport chain in mitochondria. In this study, we investigated the anti-apoptotic effects of pan-caspase inhibitor (Z-VAD), superoxide dismutase (SOD) or catalase on AMA-induced HeLa cell death in relation to the cell cycle. Treatment with Z-VAD, SOD or catalase rescued some HeLa cells from AMA-induced apoptosis, but did not prevent the growth inhibition of HeLa cells by AMA. DNA flow cytometric analysis indicated that treatment with AMA significantly induced an S-phase arrest of the cell cycle at 72 h. Interestingly, Z-VAD, SOD and catalase intensified S-phase arrest in AMA-treated cells. In conclusion, treatment with Z-VAD, SOD or catalase decreased apoptotic levels in AMA-treated cells, which was associated with the enhancement of the S-phase arrest of the cell cycle in these cells.

  13. 31P NMR saturation-transfer measurements in Saccharomyces cerevisiae: characterization of phosphate exchange reactions by iodoacetate and antimycin A inhibition

    International Nuclear Information System (INIS)

    Campbell-Burk, S.L.; Jones, K.A.; Shulman, R.G.

    1987-01-01

    31 P 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. 13 C NMR and O 2 electrode measurements were also conducted to monitor changes in rates of glucose consumption and O 2 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

  14. Effect of rainbow trout size on response to rotenone and antimycin.

    Science.gov (United States)

    Brown, Peter J.; Johnson, Heather; Zale, Alexander V.

    2011-01-01

    The piscicides rotenone and antimycin are commonly used to eradicate unwanted fish populations. However, the relationships (if present) between their toxicities and fish sizes are unknown and could be especially important when bioassay fish are used to detect piscicide presence and effectiveness. Size-mediated toxicity could lead to either excessive or inadequate piscicide applications if bioassay fish are larger or smaller than the fish being eradicated. The relationships between time to death and weight of rainbow trout Oncorhynchus mykiss (0.7–574.0 g) at an antimycin concentration of 7.5 μg/L and a rotenone concentration of 12.5 μg/L were determined. Antimycin took significantly longer than rotenone to kill rainbow trout at concentrations typically used in eradication projects. Significant positive relationships existed between fish size and time to death for rotenone and antimycin exposures and were probably caused by size-mediated differences in metabolic rate; however, these relationships accounted for less than 21% of the variation in time to death. Smaller fish appeared to be affected by the chemicals more quickly, but their deaths did not consistently occur before the deaths of larger fish.

  15. 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

    1. Cytochrome b-562 is more reduced in submitochondrial particles of mutant 28 during the aerobic steady-state respiration with succinate than in particles of the wild type. When anaerobiosis is reached, the reduction of cytochrome b is preceded by a rapid reoxidation in the mutnat. A similar reo...

  16. Cellular Quantitative Structure–Activity Relationship (Cell-QSAR): Conceptual Dissection of Receptor Binding and Intracellular Disposition in Antifilarial Activities of Selwood Antimycins

    Science.gov (United States)

    2012-01-01

    We present the cellular quantitative structure–activity relationship (cell-QSAR) concept that adapts ligand-based and receptor-based 3D-QSAR methods for use with cell-level activities. The unknown intracellular drug disposition is accounted for by the disposition function (DF), a model-based, nonlinear function of a drug’s lipophilicity, acidity, and other properties. We conceptually combined the DF with our multispecies, multimode version of the frequently used ligand-based comparative molecular field analysis (CoMFA) method, forming a single correlation function for fitting the cell-level activities. The resulting cell-QSAR model was applied to the Selwood data on filaricidal activities of antimycin analogues. Their molecules are flexible, ionize under physiologic conditions, form different intramolecular H-bonds for neutral and ionized species, and cross several membranes to reach unknown receptors. The calibrated cell-QSAR model is significantly more predictive than other models lacking the disposition part and provides valuable structure optimization clues by factorizing the cell-level activity of each compound into the contributions of the receptor binding and disposition. PMID:22468611

  17. Cellular quantitative structure-activity relationship (Cell-QSAR): conceptual dissection of receptor binding and intracellular disposition in antifilarial activities of Selwood antimycins.

    Science.gov (United States)

    Natesan, Senthil; Wang, Tiansheng; Lukacova, Viera; Bartus, Vladimir; Khandelwal, Akash; Subramaniam, Rajesh; Balaz, Stefan

    2012-04-26

    We present the cellular quantitative structure-activity relationship (cell-QSAR) concept that adapts ligand-based and receptor-based 3D-QSAR methods for use with cell-level activities. The unknown intracellular drug disposition is accounted for by the disposition function (DF), a model-based, nonlinear function of a drug's lipophilicity, acidity, and other properties. We conceptually combined the DF with our multispecies, multimode version of the frequently used ligand-based comparative molecular field analysis (CoMFA) method, forming a single correlation function for fitting the cell-level activities. The resulting cell-QSAR model was applied to the Selwood data on filaricidal activities of antimycin analogues. Their molecules are flexible, ionize under physiologic conditions, form different intramolecular H-bonds for neutral and ionized species, and cross several membranes to reach unknown receptors. The calibrated cell-QSAR model is significantly more predictive than other models lacking the disposition part and provides valuable structure optimization clues by factorizing the cell-level activity of each compound into the contributions of the receptor binding and disposition.

  18. Bcl-2 protects against apoptosis induced by antimycin A and bongkrekic acid without restoring cellular ATP levels.

    NARCIS (Netherlands)

    Graaf, A.O. de; Meijerink, J.P.P.; Heuvel, L.P.W.J. van den; Abreu, R.A. de; Witte, T.J.M. de; Jansen, J.H.; Smeitink, J.A.M.

    2002-01-01

    Several studies indicate that mitochondrial ATP production as well as ADP/ATP exchange across mitochondrial membranes are impaired during apoptosis. We investigated whether Bcl-2 could protect against cell death under conditions in which ATP metabolism is inhibited. Inhibition of ATP production

  19. 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.

  20. A High-Throughput Flow Cytometry Screen Identifies Molecules That Inhibit Hantavirus Cell Entry.

    Science.gov (United States)

    Buranda, Tione; Gineste, Catherine; Wu, Yang; Bondu, Virginie; Perez, Dominique; Lake, Kaylin R; Edwards, Bruce S; Sklar, Larry A

    2018-04-01

    Hantaviruses cause hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS), which infects more than 200,000 people worldwide. Sin Nombre virus (SNV) and Andes virus (ANDV) cause the most severe form of HCPS, with case fatality ratios of 30%-40%. There are no specific therapies or vaccines for SNV. Using high-throughput flow cytometry, we screened the Prestwick Chemical Library for small-molecule inhibitors of the binding interaction between UV-inactivated and fluorescently labeled SNV R18 particles, and decay-accelerating factor (DAF) expressed on Tanoue B cells. Eight confirmed hit compounds from the primary screen were investigated further in secondary screens that included infection inhibition, cytotoxicity, and probe interference. Antimycin emerged as a bona fide hit compound that inhibited cellular infection of the major HCPS (SNV)- and HCPS (Hantaan)-causing viruses. Confirming our assay's ability to detect active compounds, orthogonal testing of the hit compound showed that antimycin binds directly to the virus particle and blocks recapitulation of physiologic integrin activation caused by SNV binding to the integrin PSI domain.

  1. Identification of a New Isoindole-2-yl Scaffold as a Qo and Qi Dual Inhibitor of Cytochrome bc1Complex: Virtual Screening, Synthesis, and Biochemical Assay.

    Science.gov (United States)

    Azizian, Homa; Bagherzadeh, Kowsar; Shahbazi, Sophia; Sharifi, Niusha; Amanlou, Massoud

    2017-09-18

    Respiratory chain ubiquinol-cytochrome (cyt) c oxidoreductase (cyt bc 1 or complex III) has been demonstrated as a promising target for numerous antibiotics and fungicide applications. In this study, a virtual screening of NCI diversity database was carried out in order to find novel Qo/Qi cyt bc 1 complex inhibitors. Structure-based virtual screening and molecular docking methodology were employed to further screen compounds with inhibition activity against cyt bc 1 complex after extensive reliability validation protocol with cross-docking method and identification of the best score functions. Subsequently, the application of rational filtering procedure over the target database resulted in the elucidation of a novel class of cyt bc 1 complex potent inhibitors with comparable binding energies and biological activities to those of the standard inhibitor, antimycin.

  2. Utilization of adenosine triphosphate in rat mast cells during histamine release induced by the ionophore A23187

    DEFF Research Database (Denmark)

    Johansen, Torben

    1979-01-01

    The role of endogenous adenosine triphosphate (ATP) in histamine release from rat mast cells induced by the ionophore A23187 in vitro has been studied. 2 The amount of histamine released by calcium from rat mast cells primed with the ionophore A23187 was dependent on the ATP content of the mast...... cells. 3 In aerobic experiments a drastic reduction in mast cell ATP content was found during the time when histamine release induced by A23187 takes place. 4 Anaerobic experiments were performed with metabolic inhibitors (antimycin A, oligomycin, and carbonyl cyanide p...... The observations are consistent with the view that energy requiring processes are involved in ionophore-induced histamine release from rat mast cells although part of the ATP reduction in the aerobic experiments may be due to an uncoupling effect of calcium on the oxidative phosphorylation....

  3. A single Sfp-type phosphopantetheinyl transferase plays a major role in the biosynthesis of PKS and NRPS derived metabolites in Streptomyces ambofaciens ATCC23877.

    Directory of Open Access Journals (Sweden)

    Robert Bunet

    Full Text Available The phosphopantetheinyl transferases (PPTases are responsible for the activation of the carrier protein domains of the polyketide synthases (PKS, non ribosomal peptide synthases (NRPS and fatty acid synthases (FAS. The analysis of the Streptomyces ambofaciens ATCC23877 genome has revealed the presence of four putative PPTase encoding genes. One of these genes appears to be essential and is likely involved in fatty acid biosynthesis. Two other PPTase genes, samT0172 (alpN and samL0372, are located within a type II PKS gene cluster responsible for the kinamycin production and an hybrid NRPS-PKS cluster involved in antimycin production, respectively, and their products were shown to be specifically involved in the biosynthesis of these secondary metabolites. Surprisingly, the fourth PPTase gene, which is not located within a secondary metabolite gene cluster, appears to play a pleiotropic role. Its product is likely involved in the activation of the acyl- and peptidyl-carrier protein domains within all the other PKS and NRPS complexes encoded by S. ambofaciens. Indeed, the deletion of this gene affects the production of the spiramycin and stambomycin macrolide antibiotics and of the grey spore pigment, all three being PKS-derived metabolites, as well as the production of the nonribosomally produced compounds, the hydroxamate siderophore coelichelin and the pyrrolamide antibiotic congocidine. In addition, this PPTase seems to act in concert with the product of samL0372 to activate the ACP and/or PCP domains of the antimycin biosynthesis cluster which is also responsible for the production of volatile lactones.

  4. A single Sfp-type phosphopantetheinyl transferase plays a major role in the biosynthesis of PKS and NRPS derived metabolites in Streptomyces ambofaciens ATCC23877.

    Science.gov (United States)

    Bunet, Robert; Riclea, Ramona; Laureti, Luisa; Hôtel, Laurence; Paris, Cédric; Girardet, Jean-Michel; Spiteller, Dieter; Dickschat, Jeroen S; Leblond, Pierre; Aigle, Bertrand

    2014-01-01

    The phosphopantetheinyl transferases (PPTases) are responsible for the activation of the carrier protein domains of the polyketide synthases (PKS), non ribosomal peptide synthases (NRPS) and fatty acid synthases (FAS). The analysis of the Streptomyces ambofaciens ATCC23877 genome has revealed the presence of four putative PPTase encoding genes. One of these genes appears to be essential and is likely involved in fatty acid biosynthesis. Two other PPTase genes, samT0172 (alpN) and samL0372, are located within a type II PKS gene cluster responsible for the kinamycin production and an hybrid NRPS-PKS cluster involved in antimycin production, respectively, and their products were shown to be specifically involved in the biosynthesis of these secondary metabolites. Surprisingly, the fourth PPTase gene, which is not located within a secondary metabolite gene cluster, appears to play a pleiotropic role. Its product is likely involved in the activation of the acyl- and peptidyl-carrier protein domains within all the other PKS and NRPS complexes encoded by S. ambofaciens. Indeed, the deletion of this gene affects the production of the spiramycin and stambomycin macrolide antibiotics and of the grey spore pigment, all three being PKS-derived metabolites, as well as the production of the nonribosomally produced compounds, the hydroxamate siderophore coelichelin and the pyrrolamide antibiotic congocidine. In addition, this PPTase seems to act in concert with the product of samL0372 to activate the ACP and/or PCP domains of the antimycin biosynthesis cluster which is also responsible for the production of volatile lactones.

  5. Evaluation of whole antioxidant defenses of human mononuclear cells by a new in vitro biological test: lack of correlation between erythrocyte and mononuclear cell resistance to oxidative stress.

    Science.gov (United States)

    Caspar-Bauguil, Sylvie; Maestre, Nicolas; Segafredo, Céline; Galinier, Anne; Garcia, Jésus; Prost, Michel; Périquet, Brigitte; Pénicaud, Luc; Salvayre, Robert; Casteilla, Louis

    2009-04-01

    This work aims to evaluate the resistance of mononuclear cells to oxidative stress using a "KRL" test, formerly utilized to evaluate the resistance of erythrocyte to free radicals. The "KRL" test evaluates the resistance to lysis of cells treated by free radicals generated under standardized conditions. We defined new analytical parameters (level of radical production, time course, number of cells) to obtain an accurate assay determining the resistance to oxidative stress of mononuclear cells, in comparison to that of erythrocytes. This test allows the evaluation of change in the redox state of mononuclear cells (improved by an antioxidant mix or deteriorated by antimycin A-induced mitochondrial radical overproduction). Interestingly, our data show that the sensitivity of mononuclear cells to oxidative stress is not correlated with the susceptibility of erythrocytes to oxidative stress. The quantification of the susceptibility of mononuclear cells to oxidative stress gives additional information (in addition to erythrocyte resistance) and could be helpful for patients with chronic inflammation.

  6. Acetate oxidation by bloodstream forms of Trypanosoma cruzi.

    Science.gov (United States)

    Docampo, R; Cruz, F S; Leon, W; Schmunis, G A

    1979-05-01

    Bloodstream forms of Trypanosoma cruzi had a substantial increase in respiration in the presence of acetate. Oxidation of acetate took place via the tricarboxylic acid cycle and involved an antimycin A-sensitive respiratory pathway. Oxygen uptake in the presence of acetate was a sensitive to antimycin A inhibition as was CO2 production. There was a 6--7% residual O2 uptake which was not inhibited by high antimycin concentrations. Human anti-T. cruzi sera had no effect on oxygen uptake.

  7. Respiration in the yeast and mycelial phases of Histoplasma capsulatum.

    Science.gov (United States)

    Maresca, B; Lambowitz, A M; Kobayashi, G S; Medoff, G

    1979-05-01

    Respiration in the yeast and mycelial phases of Histoplasma capsulatum proceeds via a cytochrome system and an alternate oxidase, both present constitutively. The mycelial cytochrome system is distinguished by an additional partial shunt around the antimycin-sensitive site.

  8. 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.

  9. 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.

  10. Ex vivo hyperpolarized MR spectroscopy on isolated renal tubular cells: A novel technique for cell energy phenotyping.

    Science.gov (United States)

    Juul, Troels; Palm, Fredrik; Nielsen, Per Mose; Bertelsen, Lotte Bonde; Laustsen, Christoffer

    2017-08-01

    It has been demonstrated that hyperpolarized 13 C MR is a useful tool to study cultured cells. However, cells in culture can alter phenotype, which raises concerns regarding the in vivo significance of such findings. Here we investigate if metabolic phenotyping using hyperpolarized 13 C MR is suitable for cells isolated from kidney tissue, without prior cell culture. Isolation of tubular cells from freshly excised kidney tissue and treatment with either ouabain or antimycin A was investigated with hyperpolarized MR spectroscopy on a 9.4 Tesla preclinical imaging system. Isolation of tubular cells from less than 2 g of kidney tissue generally resulted in more than 10 million live tubular cells. This amount of cells was enough to yield robust signals from the conversion of 13 C-pyruvate to lactate, bicarbonate and alanine, demonstrating that metabolic flux by means of both anaerobic and aerobic pathways can be quantified using this technique. Ex vivo metabolic phenotyping using hyperpolarized 13 C MR in a preclinical system is a useful technique to study energy metabolism in freshly isolated renal tubular cells. This technique has the potential to advance our understanding of both normal cell physiology as well as pathological processes contributing to kidney disease. Magn Reson Med 78:457-461, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  11. The glucose sensor-like protein Hxs1 is a high-affinity glucose transporter and required for virulence in Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Tong-Bao Liu

    Full Text Available Cryptococcus is a major fungal pathogen that frequently causes systemic infection in patients with compromised immunity. Glucose, an important signal molecule and the preferred carbon source for Cryptococcus, plays a critical role in fungal development and virulence. Cryptococcus contains more than 50 genes sharing high sequence homology with hexose transporters in Saccharomyces cerevisiae. However, there is no report on their function in glucose sensing or transport. In this study, we investigated two hexose transporter-like proteins (Hxs1 and Hxs2 in Cryptococcus that share the highest sequence identity with the glucose sensors Snf3 and Rgt2 in S. cerevisiae. The expression of HXS1 is repressed by high glucose, while the HXS2 expression is not regulated by glucose. Functional studies showed that Hxs1 is required for fungal resistance to oxidative stress and fungal virulence. The hxs1Δ mutant exhibited a significant reduction in glucose uptake activity, indicating that Hxs1 is required for glucose uptake. Heterologous expression of Cryptococcus HXS1 rendered the S. cerevisiae mutant lacking all 20 hexose transporters a high glucose uptake activity, demonstrating that Hxs1 functions as a glucose transporter. Heterologous expression of HXS1 in the snf3Δ rgt2Δ double mutant did not complement its growth in YPD medium containing the respiration inhibitor antimycin A, suggesting that Hxs1 may not function as a glucose sensor. Taken together, our results demonstrate that Hxs1 is a high-affinity glucose transporter and required for fungal virulence.

  12. The Glucose Sensor-Like Protein Hxs1 Is a High-Affinity Glucose Transporter and Required for Virulence in Cryptococcus neoformans

    Science.gov (United States)

    Baker, Gregory M.; Fahmy, Hany; Jiang, Linghuo; Xue, Chaoyang

    2013-01-01

    Cryptococcus is a major fungal pathogen that frequently causes systemic infection in patients with compromised immunity. Glucose, an important signal molecule and the preferred carbon source for Cryptococcus, plays a critical role in fungal development and virulence. Cryptococcus contains more than 50 genes sharing high sequence homology with hexose transporters in Saccharomyces cerevisiae. However, there is no report on their function in glucose sensing or transport. In this study, we investigated two hexose transporter-like proteins (Hxs1 and Hxs2) in Cryptococcus that share the highest sequence identity with the glucose sensors Snf3 and Rgt2 in S. cerevisiae. The expression of HXS1 is repressed by high glucose, while the HXS2 expression is not regulated by glucose. Functional studies showed that Hxs1 is required for fungal resistance to oxidative stress and fungal virulence. The hxs1Δ mutant exhibited a significant reduction in glucose uptake activity, indicating that Hxs1 is required for glucose uptake. Heterologous expression of Cryptococcus HXS1 rendered the S. cerevisiae mutant lacking all 20 hexose transporters a high glucose uptake activity, demonstrating that Hxs1 functions as a glucose transporter. Heterologous expression of HXS1 in the snf3Δ rgt2Δ double mutant did not complement its growth in YPD medium containing the respiration inhibitor antimycin A, suggesting that Hxs1 may not function as a glucose sensor. Taken together, our results demonstrate that Hxs1 is a high-affinity glucose transporter and required for fungal virulence. PMID:23691177

  13. The glucose sensor-like protein Hxs1 is a high-affinity glucose transporter and required for virulence in Cryptococcus neoformans.

    Science.gov (United States)

    Liu, Tong-Bao; Wang, Yina; Baker, Gregory M; Fahmy, Hany; Jiang, Linghuo; Xue, Chaoyang

    2013-01-01

    Cryptococcus is a major fungal pathogen that frequently causes systemic infection in patients with compromised immunity. Glucose, an important signal molecule and the preferred carbon source for Cryptococcus, plays a critical role in fungal development and virulence. Cryptococcus contains more than 50 genes sharing high sequence homology with hexose transporters in Saccharomyces cerevisiae. However, there is no report on their function in glucose sensing or transport. In this study, we investigated two hexose transporter-like proteins (Hxs1 and Hxs2) in Cryptococcus that share the highest sequence identity with the glucose sensors Snf3 and Rgt2 in S. cerevisiae. The expression of HXS1 is repressed by high glucose, while the HXS2 expression is not regulated by glucose. Functional studies showed that Hxs1 is required for fungal resistance to oxidative stress and fungal virulence. The hxs1Δ mutant exhibited a significant reduction in glucose uptake activity, indicating that Hxs1 is required for glucose uptake. Heterologous expression of Cryptococcus HXS1 rendered the S. cerevisiae mutant lacking all 20 hexose transporters a high glucose uptake activity, demonstrating that Hxs1 functions as a glucose transporter. Heterologous expression of HXS1 in the snf3Δ rgt2Δ double mutant did not complement its growth in YPD medium containing the respiration inhibitor antimycin A, suggesting that Hxs1 may not function as a glucose sensor. Taken together, our results demonstrate that Hxs1 is a high-affinity glucose transporter and required for fungal virulence.

  14. Bovine mitochondrial oxygen consumption effects on oxymyoglobin in the presence of lactate as a substrate for respiration.

    Science.gov (United States)

    Ramanathan, R; Mancini, R A; Joseph, P; Suman, S P

    2013-04-01

    Research suggests that NADH formed from lactate addition can increase mitochondrial oxygen consumption. However, limited research has assessed the subsequent effects of lactate-mediated mitochondrial oxygen consumption on oxymyoglobin. Therefore, our objective was to assess the effects of bovine mitochondrial oxygen consumption on oxymyoglobin in the presence of lactate, LDH, and NAD. Isolated beef cardiac and skeletal muscle mitochondria (n=5) were reacted with lactate (40 mM), LDH (100 units), and NAD (0.02 mM) to initiate oxygen consumption. Myoglobin redox state was measured to assess the effects of oxygen consumption on oxymyoglobin. The addition of lactate-LDH-NAD to mitochondria increased (p<0.05) both oxygen consumption and conversion of oxymyoglobin to deoxymyoglobin compared with control mitochondria without substrates. The addition of antimycin A to mitochondria decreased oxygen consumption and deoxymyoglobin formation (p<0.05). The results suggest that increased oxygen consumption can influence myoglobin redox state and this effect might be partially responsible for the darkening effect in lactate enhanced beef. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Deletion of mitochondrial ATPase inhibitor in the yeast Saccharomyces cerevisiae decreased cellular and mitochondrial ATP levels under non-nutritional conditions and induced a respiration-deficient cell-type.

    Science.gov (United States)

    Lu, Y M; Miyazawa, K; Yamaguchi, K; Nowaki, K; Iwatsuki, H; Wakamatsu, Y; Ichikawa, N; Hashimoto, T

    2001-12-01

    T(1), a mutant yeast lacking three regulatory proteins of F(1)F(o)ATPase, namely ATPase inhibitor, 9K protein and 15K protein, grew on non-fermentable carbon source at the same rate as normal cells but was less viable when incubated in water. During the incubation, the cellular ATP content decreased rapidly in the T(1) cells but not in normal cells, and respiration-deficient cells appeared among the T(1) cells. The same mutation was also induced in D26 cells lacking only the ATPase inhibitor. Overexpression of the ATPase inhibitor in YC63 cells, which were derived from the D26 strain harboring an expression vector containing the gene of the ATPase inhibitor, prevented the decrease of cellular ATP level and the mutation. Isolated T(1) mitochondria exhibited ATP hydrolysis for maintenance of membrane potential when antimycin A was added to the mitochondrial suspension, while normal and YC63 mitochondria continued to show low hydrolytic activity and low membrane potential. Thus, it is likely that deletion of the ATPase inhibitor induces ATPase activity of F(1)F(o)ATPase to create a dispensable membrane potential under the non-nutritional conditions and that this depletes mitochondrial and cellular ATP. The depletion of mitochondrial ATP in turn leads to occurrence of aberrant DNA in mitochondria.

  16. Putting together a plasma membrane NADH oxidase: a tale of three laboratories.

    Science.gov (United States)

    Löw, Hans; Crane, Frederick L; Morré, D James

    2012-11-01

    The observation that high cellular concentrations of NADH were associated with low adenylate cyclase activity led to a search for the mechanism of the effect. Since cyclase is in the plasma membrane, we considered the membrane might have a site for NADH action, and that NADH might be oxidized at that site. A test for NADH oxidase showed very low activity, which could be increased by adding growth factors. The plasma membrane oxidase was not inhibited by inhibitors of mitochondrial NADH oxidase such as cyanide, rotenone or antimycin. Stimulation of the plasma membrane oxidase by iso-proterenol or triiodothyronine was different from lack of stimulation in endoplasmic reticulum. After 25 years of research, three components of a trans membrane NADH oxidase have been discovered. Flavoprotein NADH coenzyme Q reductases (NADH cytochrome b reductase) on the inside, coenzyme Q in the middle, and a coenzyme Q oxidase on the outside as a terminal oxidase. The external oxidase segment is a copper protein with unique properties in timekeeping, protein disulfide isomerase and endogenous NADH oxidase activity, which affords a mechanism for control of cell growth by the overall NADH oxidase and the remarkable inhibition of oxidase activity and growth of cancer cells by a wide range of anti-tumor drugs. A second trans plasma membrane electron transport system has been found in voltage dependent anion channel (VDAC), which has NADH ferricyanide reductase activity. This activity must be considered in relation to ferricyanide stimulation of growth and increased VDAC antibodies in patients with autism. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Differential reduction of reactive oxygen species by human ...

    Indian Academy of Sciences (India)

    In this study, for the first time, we investigated the differences in the reactive oxygen species (ROS) reductionabilities of tissue-specific MSCs to mitigate cellular damage in oxidative stress. Hepatic Stellate cells (LX-2) and cardiomyocyteswere treated with Antimycin A (AMA) to induce oxidative stress and tissue specific ...

  18. Differential reduction of reactive oxygen species by human tissue ...

    Indian Academy of Sciences (India)

    Swati Paliwal

    2017-06-24

    Jun 24, 2017 ... Keywords. Oxidative stress; reactive oxygen species; tissue-specific mesenchymal stem cells. Abbreviations: AD, adipose; AMA, Antimycin A; AU, arbitrary units; BM, bone marrow; DP, dental pulp; MFI, mean fluorescence intensity; MSC, mesenchymal stem cell; ROS, reactive oxygen species. 1. Introduction.

  19. 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 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.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.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.

  20. Kinetics of Molybdenum Reduction to Molybdenum Blue by Bacillus sp. Strain A.rzi

    Directory of Open Access Journals (Sweden)

    A. R. Othman

    2013-01-01

    Full Text Available Molybdenum is very toxic to agricultural animals. Mo-reducing bacterium can be used to immobilize soluble molybdenum to insoluble forms, reducing its toxicity in the process. In this work the isolation of a novel molybdate-reducing Gram positive bacterium tentatively identified as Bacillus sp. strain A.rzi from a metal-contaminated soil is reported. The cellular reduction of molybdate to molybdenum blue occurred optimally at 4 mM phosphate, using 1% (w/v glucose, 50 mM molybdate, between 28 and 30°C and at pH 7.3. The spectrum of the Mo-blue product showed a maximum peak at 865 nm and a shoulder at 700 nm. Inhibitors of bacterial electron transport system (ETS such as rotenone, sodium azide, antimycin A, and potassium cyanide could not inhibit the molybdenum-reducing activity. At 0.1 mM, mercury, copper, cadmium, arsenic, lead, chromium, cobalt, and zinc showed strong inhibition on molybdate reduction by crude enzyme. The best model that fitted the experimental data well was Luong followed by Haldane and Monod. The calculated value for Luong’s constants pmax, Ks, Sm, and n was 5.88 μmole Mo-blue hr−1, 70.36 mM, 108.22 mM, and 0.74, respectively. The characteristics of this bacterium make it an ideal tool for bioremediation of molybdenum pollution.

  1. Reactive oxygen species in unstimulated hemocytes of the pacific oyster Crassostrea gigas: a mitochondrial involvement.

    Directory of Open Access Journals (Sweden)

    Ludovic Donaghy

    Full Text Available The Pacific oyster Crassostrea gigas is a sessile bivalve mollusc whose homeostasis relies, at least partially, upon cells circulating in hemolymph and referred to as hemocytes. Oyster's hemocytes have been reported to produce reactive oxygen species (ROS, even in absence of stimulation. Although ROS production in bivalve molluscs is mostly studied for its defence involvement, ROS may also be involved in cellular and tissue homeostasis. ROS sources have not yet been described in oyster hemocytes. The objective of the present work was to characterize the ROS sources in unstimulated hemocytes. We studied the effects of chemical inhibitors on the ROS production and the mitochondrial membrane potential (Δψ(m of hemocytes. First, this work confirmed the specificity of JC-10 probe to measure Δψ(m in oyster hemocytes, without being affected by ΔpH, as reported in mammalian cells. Second, results show that ROS production in unstimulated hemocytes does not originate from cytoplasmic NADPH-oxidase, nitric oxide synthase or myeloperoxidase, but from mitochondria. In contrast to mammalian cells, incubation of hemocytes with rotenone (complex I inhibitor had no effect on ROS production. Incubation with antimycin A (complex III inhibitor resulted in a dose-dependent ROS production decrease while an over-production is usually reported in vertebrates. In hemocytes of C. gigas, the production of ROS seems similarly dependent on both Δψ(m and ΔpH. These findings point out differences between mammalian models and bivalve cells, which warrant further investigation about the fine characterization of the electron transfer chain and the respective involvement of mitochondrial complexes in ROS production in hemocytes of bivalve molluscs.

  2. 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

  3. Inhibition of oxidative phosphorylation for enhancing citric acid production by Aspergillus niger.

    Science.gov (United States)

    Wang, Lu; Zhang, Jianhua; Cao, Zhanglei; Wang, Yajun; Gao, Qiang; Zhang, Jian; Wang, Depei

    2015-01-16

    The spore germination rate and growth characteristics were compared between the citric acid high-yield strain Aspergillus niger CGMCC 5751 and A. niger ATCC 1015 in media containing antimycin A or DNP. We inferred that differences in citric acid yield might be due to differences in energy metabolism between these strains. To explore the impact of energy metabolism on citric acid production, the changes in intracellular ATP, NADH and NADH/NAD+ were measured at various fermentation stages. In addition, the effects of antimycin A or DNP on energy metabolism and citric acid production was investigated by CGMCC 5751. By comparing the spore germination rate and the extent of growth on PDA plates containing antimycin A or DNP, CGMCC 5751 was shown to be more sensitive to antimycin A than ATCC 1015. The substrate-level phosphorylation of CGMCC 5751 was greater than that of ATCC 1015 on PDA plates with DNP. DNP at tested concentrations had no apparent effect on the growth of CGMCC 5751. There were no apparent effects on the mycelial morphology, the growth of mycelial pellets or the dry cell mass when 0.2 mg L(-1) antimycin A or 0.1 mg L(-1) DNP was added to medium at the 24-h time point. The concentrations of intracellular ATP, NADH and NADH/NAD+ of CGMCC 5751 were notably lower than those of ATCC 1015 at several fermentation stages. Moreover, at 96 h of fermentation, the citric acid production of CGMCC 5751 reached up to 151.67 g L(-1) and 135.78 g L(-1) by adding 0.2 mg L(-1) antimycin A or 0.1 mg L(-1) DNP, respectively, at the 24-h time point of fermentation. Thus, the citric acid production of CGMCC 5751 was increased by 19.89% and 7.32%, respectively. The concentrations of intracellular ATP, NADH and NADH/NAD+ of the citric acid high-yield strain CGMCC 5751 were notably lower than those of ATCC 1015. The excessive ATP has a strong inhibitory effect on citric acid accumulation by A. niger. Increasing NADH oxidation and appropriately reducing the concentration of

  4. Characterization of the respiratory chain of Helicobacter pylori

    DEFF Research Database (Denmark)

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

    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...

  5. Oxidative DNA damage causes mitochondrial genomic instability in Saccharomyces cerevisiae.

    Science.gov (United States)

    Doudican, Nicole A; Song, Binwei; Shadel, Gerald S; Doetsch, Paul W

    2005-06-01

    Mitochondria contain their own genome, the integrity of which is required for normal cellular energy metabolism. Reactive oxygen species (ROS) produced by normal mitochondrial respiration can damage cellular macromolecules, including mitochondrial DNA (mtDNA), and have been implicated in degenerative diseases, cancer, and aging. We developed strategies to elevate mitochondrial oxidative stress by exposure to antimycin and H(2)O(2) or utilizing mutants lacking mitochondrial superoxide dismutase (sod2Delta). Experiments were conducted with strains compromised in mitochondrial base excision repair (ntg1Delta) and oxidative damage resistance (pif1Delta) in order to delineate the relationship between these pathways. We observed enhanced ROS production, resulting in a direct increase in oxidative mtDNA damage and mutagenesis. Repair-deficient mutants exposed to oxidative stress conditions exhibited profound genomic instability. Elimination of Ntg1p and Pif1p resulted in a synergistic corruption of respiratory competency upon exposure to antimycin and H(2)O(2). Mitochondrial genomic integrity was substantially compromised in ntg1Delta pif1Delta sod2Delta strains, since these cells exhibit a total loss of mtDNA. A stable respiration-defective strain, possessing a normal complement of mtDNA damage resistance pathways, exhibited a complete loss of mtDNA upon exposure to antimycin and H(2)O(2). This loss was preventable by Sod2p overexpression. These results provide direct evidence that oxidative mtDNA damage can be a major contributor to mitochondrial genomic instability and demonstrate cooperation of Ntg1p and Pif1p to resist the introduction of lesions into the mitochondrial genome.

  6. Characterization of the respiratory chain of Helicobacter pylori

    DEFF Research Database (Denmark)

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

    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...

  7. The critical glucose concentration for respiration-independent proliferation of fission yeast, Schizosaccharomyces pombe.

    Science.gov (United States)

    Takeda, Kojiro; Starzynski, Caroline; Mori, Ayaka; Yanagida, Mitsuhiro

    2015-05-01

    Glucose is the fundamental energy source for life; thus cells need to respond appropriately to changes in available glucose concentration. We investigated the relationship between media glucose concentration and respiration-dependency of proliferation, using Schizosaccharomyces pombe. In media containing ≥ 0.2% glucose, neither antimycin A, an inhibitor of Complex III, nor gene deletions of essential electron transfer chain components, impaired cell division, while these factors completely inhibited cell division in media containing ≤ 0.1% glucose. These results indicate the existence of a threshold in glucose concentration that governs respiration-dependency of S. pombe proliferation. Copyright © 2015. Published by Elsevier B.V.

  8. 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...... pretreated with 2-deoxyglucose. The release of histamine from these cells was reduced when respiratory inhibitors were added to the cell suspension 5 to 20 sec after exposure of the cells to antigen. This may indicate that the secretory process requires energy, and it seems necessary that energy should...... be produced as the release of histamine takes place....

  9. Cyanide-insensitive respiration in Acanthamoeba castellanii. Changes in sensitivity of whole cell respiration during exponential growth

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, S.W.; Lloyd, D.

    1977-01-01

    Respiration of Acanthamoeba castellanii shows varying sensitivity to cyanide during exponential growth in a medium containing proteose peptone, glucose and yeast extract. After 20 h growth, respiration was stimulated up to 40% by I mM-cyanide; sensitivity to cyanide then gradually increased until 90% inhibition of respiration was attained in late exponential phase cultures. Salicyl hydroxamic acid alone never stimulated or inhibited respiration by more than 20% but, when added together with cyanide, inhibition was always 70 to 100% from 3 h onward. Sensitivity to antimycin A was similar, but not identical to that shown to cyanide; when antimycin A was added together with salicyl hydroxamic acid, the inhibition was greater. Increased sensitivities to arsenite and malonate were also observed in late-exponential phase cultures. These changes in sensitivities were not associated with alterations in the growth medium since similar changes in sensitivity to inhibitors were observed during growth in conditioned medium. A rotenone-sensitive site is associated with cyanide-stimulated respiration and the results suggest that A. castellanii possesses a branched electron transport system.

  10. Substance P receptor desensitization requires receptor activation but not phospholipase C

    International Nuclear Information System (INIS)

    Sugiya, Hiroshi; Putney, J.W. Jr.

    1988-01-01

    Previous studies have shown that exposure of parotid acinar cells to substance P at 37 degree C results in activation of phospholipase C, formation of [ 3 H]inositol 1,4,5-trisphosphate (IP 3 ), and persistent desensitization of the substance P response. In cells treated with antimycin in medium containing glucose, ATP was decreased to ∼20% of control values, IP 3 formation was completely inhibited, but desensitization was unaffected. When cells were treated with antimycin in the absence of glucose, cellular ATP was decreased to ∼5% of control values, and both IP 3 formation and desensitization were blocked. A series of substance P-related peptides increased the formation of [ 3 H]IP 3 and induced desensitization of the substance P response with a similar rank order of potencies. The substance P antagonist, [D-Pro 2 , D-Try 7,9 ]-substance P, inhibited substance P-induced IP 3 formation and desensitization but did not induce desensitization. These results suggest that the desensitization of substance P-induced IP 3 formation requires agonist activation of a P-type substance P receptor, and that one or more cellular ATP-dependent processes are required for this reaction. However, activation of phospholipase C and the generation of inositol phosphates does not seem to be a prerequisite for desensitization

  11. Alternative respiration and fumaric acid production of Rhizopus oryzae.

    Science.gov (United States)

    Gu, Shuai; Xu, Qing; Huang, He; Li, Shuang

    2014-06-01

    Under the conditions of fumaric acid fermentation, Rhizopus oryzae ME-F14 possessed at least two respiratory systems. The respiration of mycelia was partially inhibited by the cytochrome respiration inhibitor antimycin A or the alternative respiration inhibitor salicylhydroxamic acid and was completely inhibited in the presence of both antimycin A and salicylhydroxamic acid. During fumaric acid fermentation process, the activity of alternative respiration had a great correlation with fumaric acid productivity; both of them reached peak at the same time. The alternative oxidase gene, which encoded the mitochondrial alternative oxidase responsible for alternative respiration in R. oryzae ME-F14, was cloned and characterized in Escherichia coli. The activity of alternative respiration, the alternative oxidase gene transcription level, as well as the fumaric acid titer were measured under different carbon sources and different carbon-nitrogen ratios. The activity of alternative respiration was found to be comparable to the transcription level of the alternative oxidase gene and the fumaric acid titer. These results indicated that the activity of the alternative oxidase was regulated at the transcription stage under the conditions tested for R. oryzae ME-F14.

  12. 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.

  13. The influence of ascorbic acid on the oxygen consumption and the heat production by the cells of wheat seedling roots with their mitochondrial electron transport chain inhibited at complexes I and III

    International Nuclear Information System (INIS)

    Gordon, L.K.; Rakhmatullina, D.F.; Ogorodnikova, T.I.; Alyabyev, A.J.; Minibayeva, F.V.; Loseva, N.L.; Mityashina, S.Y.

    2007-01-01

    The influence of exogenous ascorbic acid (AsA) on oxidative phosphorylation was studied using wheat seedling roots. Treatment of them with AsA stimulated the rates of oxygen consumption and the heat production and caused a decrease of the respiratory coefficient. The increase in respiration was prevented by inhibitors of ascorbate oxidase, diethyldithiocarbamate (DEDTC), and of cytochrome oxidase, cyanide (KCN). Exogenous AsA sharply stimulated the rate of oxygen consumption of roots when complexes I and III of the mitochondrial electron transport chain were inhibited by rotenone and antimycin A, respectively, while the rates of heat production did not change significantly. It is concluded that AsA is a potent energy substrate, which can be used in conditions of failing I and III complexes in the mitochondrial electron transport chain

  14. 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...... and the cellular ATP content at the time of cell activation was demonstrated. This may indicate a direct link between ATP and the secretory mechanism. 3. The possibility of an increased utilization of ATP during histamine secretion was explored in mast cells exposed to metabolic inhibitors. Incubation of mast...... cells with 2-deoxyglucose (2-DG) decreased the ATP content of the cells, and a long-lasting and stable level of mast cell ATP was observed. This is explained by a small decrease in the rate of ATP-synthesis by 2-DG. In 2-DG-treated cells secretion of histamine in response to compound 48...

  15. 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....... Furthermore, the inhibition of histamine release occurred mainly through interaction with thiol groups, although inhibition of cellular energy production may have been an additional mechanism....... as well as in presence of 2-deoxyglucose. A23187-induced histamine release was inhibited by ethacrynic acid, and this inhibition was completely reversed by dithiothreitol. These observations may indicate that ethacrynic acid inhibits glycolytic and respiratory energy production in rat mast cells...

  16. Expression of Arabidopsis gdh2 gene depends on activity of alternative electron transfer pathway in mitochondria

    Directory of Open Access Journals (Sweden)

    Konstantinov Yu. M.

    2012-09-01

    Full Text Available Aim. We studied the expression level of gdh2 gene, encoding subunit of mitochondrial glutamate dehydrogenase, in Arabidopsis suspension culture cells with genetically modified level of alternative oxidase AOX1a. Methods. Polymerase chain reaction, Northern-blotting. Results. The treatment with main electron transfer pathway inhibitor antimycin A led to an increase in gdh2 transcript level in the wild-type cells and the cells with decreased level of alternative oxidase, but not in the cells with elevated level of alternative oxidase. Conclusions. It is known that an increase in alternative oxidase level in the plant cell results in more oxidized state of ubiquinone pool in respiratory chain. Therefore, the obtained results support the earlier proposed model according to which the expression level of gdh2 gene depends on the redox state of ubiquinone pool.

  17. 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

    The Na+/K(+)-pump activity and the utilization of adenosine triphosphate (ATP) were studied in rat peritoneal mast cells after histamine secretion induced by compound 48/80. We measured the ouabain-sensitive K(+)-uptake by a radioactive technique (86Rb+). The ATP content and the glycolytic ATP......-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+/K(+)-pump....... The anaerobic, but not the aerobic, pathway for ATP-synthesis was able to respond to the increased ATP-requirement. The ATP-requirement of the Na+/K(+)-pump was only partly satisfied when ATP was supplied from either the glycolytic or the oxidative pathway. This may indicate that the availability of ATP...

  18. The effect of metabolic inhibitors on the development of respiration in anaerobically grown yeast

    Science.gov (United States)

    Bartley, W.; Tustanoff, E. R.

    1966-01-01

    1. Iodoacetate and fluoride did not prevent the development of respiration in aerobically grown yeast. 2. The effect of dinitrophenol suggested that phosphorylation developed simultaneously with respiration in anaerobically grown yeast, but the effect of oligomycin suggested that the phosphorylation and oxidation were not tightly coupled. 3. Inhibitors of electron transport showed that both the respiratory peak and the subsequent respiration were cyanide-sensitive, but the peak respiration was insensitive to antimycin. 4. Of the inhibitors of protein or RNA synthesis tested, only p-fluorophenylalanine inhibited the development of respiration. The results are not consistent with a new synthesis of mitochondria. 5. 2-Phenylethanol inhibited the development of respiration in anaerobically grown yeast and also yeast growth. Other inhibitors of DNA synthesis had no effect on the development of respiration. 6. The relevance of the results to mitochondrial morphogenesis is discussed. PMID:4290405

  19. Role of mitochondria in modulation of spontaneous Ca2+ waves in freshly dispersed interstitial cells of Cajal from the rabbit urethra.

    Science.gov (United States)

    Sergeant, Gerard P; Bradley, Eamonn; Thornbury, Keith D; McHale, Noel G; Hollywood, Mark A

    2008-10-01

    Interstitial cells of Cajal (ICC) isolated from the rabbit urethra exhibit pacemaker activity that results from spontaneous Ca(2+) waves. The purpose of this study was to investigate if this activity was influenced by Ca(2+) uptake into mitochondria. Spontaneous Ca(2+) waves were recorded using a Nipkow spinning disk confocal microscope and spontaneous transient inward currents (STICs) were recorded using the whole-cell patch clamp technique. Disruption of the mitochondrial membrane potential with the electron transport chain inhibitors rotenone (10 microm) and antimycin A (5 microm) abolished Ca(2+) waves and increased basal Ca(2+) levels. Similar results were achieved when mitochondria membrane potential was collapsed using the protonophores FCCP (0.2 microm) and CCCP (1 microm). Spontaneous Ca(2+) waves were not inhibited by the ATP synthase inhibitor oligomycin (1 microm), suggesting that these effects were not attributable to an effect on ATP levels. STICs recorded under voltage clamp at -60 mV were also inhibited by CCCP and antimycin A. Dialysis of cells with the mitochondrial uniporter inhibitor RU360 (10 microm) also inhibited STICS. Stimulation of Ca(2+) uptake into mitochondria using the plant flavonoid kaempferol (10 microm) induced a series of propagating Ca(2+) waves. The kaempferol-induced activity was inhibited by application of caffeine (10 mm) or removal of extracellular Ca(2+), but was not significantly affected by the IP(3) receptor blocker 2-APB (100 microm). These data suggest that spontaneous Ca(2+) waves in urethral ICC are regulated by buffering of cytoplasmic Ca(2+) by mitochondria.

  20. 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).

  1. Role of mitochondria in modulation of spontaneous Ca2+ waves in freshly dispersed interstitial cells of Cajal from the rabbit urethra

    Science.gov (United States)

    Sergeant, Gerard P; Bradley, Eamonn; Thornbury, Keith D; McHale, Noel G; Hollywood, Mark A

    2008-01-01

    Interstitial cells of Cajal (ICC) isolated from the rabbit urethra exhibit pacemaker activity that results from spontaneous Ca2+ waves. The purpose of this study was to investigate if this activity was influenced by Ca2+ uptake into mitochondria. Spontaneous Ca2+ waves were recorded using a Nipkow spinning disk confocal microscope and spontaneous transient inward currents (STICs) were recorded using the whole-cell patch clamp technique. Disruption of the mitochondrial membrane potential with the electron transport chain inhibitors rotenone (10 μm) and antimycin A (5 μm) abolished Ca2+ waves and increased basal Ca2+ levels. Similar results were achieved when mitochondria membrane potential was collapsed using the protonophores FCCP (0.2 μm) and CCCP (1 μm). Spontaneous Ca2+ waves were not inhibited by the ATP synthase inhibitor oligomycin (1 μm), suggesting that these effects were not attributable to an effect on ATP levels. STICs recorded under voltage clamp at −60 mV were also inhibited by CCCP and antimycin A. Dialysis of cells with the mitochondrial uniporter inhibitor RU360 (10 μm) also inhibited STICS. Stimulation of Ca2+ uptake into mitochondria using the plant flavonoid kaempferol (10 μm) induced a series of propagating Ca2+ waves. The kaempferol-induced activity was inhibited by application of caffeine (10 mm) or removal of extracellular Ca2+, but was not significantly affected by the IP3 receptor blocker 2-APB (100 μm). These data suggest that spontaneous Ca2+ waves in urethral ICC are regulated by buffering of cytoplasmic Ca2+ by mitochondria. PMID:18703577

  2. Anticancer Drug 2-Methoxyestradiol Protects against Renal Ischemia/Reperfusion Injury by Reducing Inflammatory Cytokines Expression

    Directory of Open Access Journals (Sweden)

    Ying-Yin Chen

    2014-01-01

    Full Text Available Background. Ischemia/reperfusion (I/R injury is a major cause of acute renal failure and allograft dysfunction in kidney transplantation. ROS/inflammatory cytokines are involved in I/R injury. 2-Methoxyestradiol (2ME2, an endogenous metabolite of estradiol, inhibits inflammatory cytokine expression and is an antiangiogenic and antitumor agent. We investigated the inhibitory effect of 2ME2 on renal I/R injury and possible molecular actions. Methods. BALB/c mice were intraperitoneally injected with 2ME2 (10 or 20 mg/kg or vehicle 12 h before and immediately after renal I/R experiments. The kidney weight, renal function, tubular damages, and apoptotic response were examined 24 h after I/R injury. The expression of mRNA of interleukin-1β, tumor necrosis factor- (TNF α, caspase-3, hypoxia inducible factor- (HIF 1α, and proapoptotic Bcl-2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3 in kidney tissue was determined using RT-PCR, while the expression of nuclear factor κB (NF-κB, BCL-2, and BCL-xL, activated caspase-9, and HIF-1α was determined using immunoblotting. In vitro, we determined the effect of 2ME2 on reactive oxygen species (ROS production and cell viability in antimycin-A-treated renal mesangial (RMC and tubular (NRK52E cells. Results. Serum creatinine and blood urea nitrogen were significantly higher in mice with renal I/R injury than in sham control and in I/R+2ME2-treated mice. Survival in I/R+2ME2-treated mice was higher than in I/R mice. Histological examination showed that 2ME2 attenuated tubular damage in I/R mice, which was associated with lower expression TNF-α, IL-1β, caspase-9, HIF-1α, and BNIP3 mRNA in kidney tissue. Western blotting showed that 2ME2 treatment substantially decreased the expression of activated caspase-9, NF-κB, and HIF-1α but increased the antiapoptotic proteins BCL-2 and BCL-xL in kidney of I/R injury. In vitro, 2MR2 decreased ROS production and increased cell viability in antimycin-A

  3. Studies on the mechanism of synthesis of ethyl acetate in Kluyveromyces marxianus DSM 5422.

    Science.gov (United States)

    Löser, Christian; Urit, Thanet; Keil, Peter; Bley, Thomas

    2015-02-01

    Kluyveromyces marxianus converts whey-borne sugar into ethyl acetate, an environmentally friendly solvent with many applications. K. marxianus DSM 5422 presumably synthesizes ethyl acetate from acetyl-SCoA. Iron limitation as a trigger for this synthesis is explained by a diminished aconitase and succinate dehydrogenase activity (both enzymes depend on iron) causing diversion of acetyl-SCoA from the tricarboxic acid cycle to ester synthesis. Copper limitation as another trigger for ester synthesis in this yeast refers to involvement of the electron transport chain (all ETC complexes depend on iron and complex IV requires copper). This hypothesis was checked by using several ETC inhibitors. Malonate was ineffective but carboxin partially inhibited complex II and initiated ester synthesis. Antimycin A and cyanide as complexes III and IV inhibitors initiated ester synthesis only at moderate levels while higher concentrations disrupted all respiration and caused ethanol formation. A restricted supply of oxygen (the terminal electron acceptor) also initiated some ester synthesis but primarily forced ethanol production. A switch from aerobic to anaerobic conditions nearly stopped ester synthesis and induced ethanol formation. Iron-limited ester formation was compared with anaerobic ethanol production; the ester yield was lower than the ethanol yield but a higher market price, a reduced number of process stages, a faster process, and decreased expenses for product recovery by stripping favor biotechnological ester production.

  4. 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.

  5. Different molecular mechanisms involved in spontaneous and oxidative stress-induced mitochondrial fragmentation in tripeptidyl peptidase-1 (TPP-1)-deficient fibroblasts.

    Science.gov (United States)

    Van Beersel, Guillaume; Tihon, Eliane; Demine, Stéphane; Hamer, Isabelle; Jadot, Michel; Arnould, Thierry

    2013-02-07

    NCLs (neuronal ceroid lipofuscinoses) form a group of eight inherited autosomal recessive diseases characterized by the intralysosomal accumulation of autofluorescent pigments, called ceroids. Recent data suggest that the pathogenesis of NCL is associated with the appearance of fragmented mitochondria with altered functions. However, even if an impairement in the autophagic pathway has often been evoked, the molecular mechanisms leading to mitochondrial fragmentation in response to a lysosomal dysfunction are still poorly understood. In this study, we show that fibroblasts that are deficient for the TPP-1 (tripeptidyl peptidase-1), a lysosomal hydrolase encoded by the gene mutated in the LINCL (late infantile NCL, CLN2 form) also exhibit a fragmented mitochondrial network. This morphological alteration is accompanied by an increase in the expression of the protein BNIP3 (Bcl2/adenovirus E1B 19 kDa interacting protein 3) as well as a decrease in the abundance of mitofusins 1 and 2, two proteins involved in mitochondrial fusion. Using RNAi (RNA interference) and quantitative analysis of the mitochondrial morphology, we show that the inhibition of BNIP3 expression does not result in an increase in the reticulation of the mitochondrial population in LINCL cells. However, this protein seems to play a key role in cell response to mitochondrial oxidative stress as it sensitizes mitochondria to antimycin A-induced fragmentation. To our knowledge, our results bring the first evidence of a mechanism that links TPP-1 deficiency and oxidative stress-induced changes in mitochondrial morphology.

  6. 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.

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

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    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.

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

    International Nuclear Information System (INIS)

    Kondo-Nakamura, Mihoko; Shintani-Ishida, Kaori; Uemura, Koichi; Yoshida, Ken-ichi

    2010-01-01

    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 O 2 - 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 O 2 - scavenger (Tiron), catalase or a superoxide dismutase (SOD) inhibitor (DETC). These results suggest that CO pretreatment induces mitochondrial generation of O 2 - , which is then converted by SOD to H 2 O 2 , and subsequent Akt activation by H 2 O 2 attenuates apoptosis in ischemia-reperfusion.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kondo-Nakamura, Mihoko [Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shintani-Ishida, Kaori, E-mail: kaori@m.u-tokyo.ac.jp [Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Uemura, Koichi; Yoshida, Ken-ichi [Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2010-03-12

    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 O{sub 2}{sup -} 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 O{sub 2}{sup -} scavenger (Tiron), catalase or a superoxide dismutase (SOD) inhibitor (DETC). These results suggest that CO pretreatment induces mitochondrial generation of O{sub 2}{sup -}, which is then converted by SOD to H{sub 2}O{sub 2}, and subsequent Akt activation by H{sub 2}O{sub 2} attenuates apoptosis in ischemia-reperfusion.

  10. Peroxynitrite formation in nitric oxide-exposed submitochondrial particles: detection, oxidative damage and catalytic removal by Mn-porphyrins.

    Science.gov (United States)

    Valez, Valeria; Cassina, Adriana; Batinic-Haberle, Ines; Kalyanaraman, Balaraman; Ferrer-Sueta, Gerardo; Radi, Rafael

    2013-01-01

    Peroxynitrite (ONOO(-)) formation in mitochondria may be favored due to the constant supply of superoxide radical (O(2)(∙-)) by the electron transport chain plus the facile diffusion of nitric oxide ((∙)NO) to this organelle. Herein, a model system of submitochondrial particles (SMP) in the presence of succinate plus the respiratory inhibitor antimycin A (to increase O(2)(∙-) rates) and the (∙)NO-donor NOC-7 was studied to directly establish and quantitate peroxynitrite by a multiplicity of methods including chemiluminescence, fluorescence and immunochemical analysis. While all the tested probes revealed peroxynitrite at near stoichiometric levels with respect to its precursor radicals, coumarin boronic acid (a probe that directly reacts with peroxynitrite) had the more straightforward oxidation profile from O(2)(∙-)-forming SMP as a function of the (∙)NO flux. Interestingly, immunospintrapping studies verified protein radical generation in SMP by peroxynitrite. Substrate-supplemented SMP also reduced Mn(III)porphyrins (MnP) to Mn(II)P under physiologically-relevant oxygen levels (3-30 μM); then, Mn(II)P were capable to reduce peroxynitrite and protect SMP from the inhibition of complex I-dependent oxygen consumption and protein radical formation and nitration of membranes. The data directly support the formation of peroxynitrite in mitochondria and demonstrate that MnP can undergo a catalytic redox cycle to neutralize peroxynitrite-dependent mitochondrial oxidative damage. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

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    Shohei Sakuda

    2014-03-01

    Full Text Available Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control.

  12. 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.

  13. Diabetes increases susceptibility of primary cultures of rat proximal tubular cells to chemically induced injury

    International Nuclear Information System (INIS)

    Zhong Qing; Terlecky, Stanley R.; Lash, Lawrence H.

    2009-01-01

    Diabetic nephropathy is characterized by increased oxidative stress and mitochondrial dysfunction. In the present study, we prepared primary cultures of proximal tubular (PT) cells from diabetic rats 30 days after an ip injection of streptozotocin and compared their susceptibility to oxidants (tert-butyl hydroperoxide, methyl vinyl ketone) and a mitochondrial toxicant (antimycin A) with that of PT cells isolated from age-matched control rats, to test the hypothesis that PT cells from diabetic rats exhibit more cellular and mitochondrial injury than those from control rats when exposed to these toxicants. PT cells from diabetic rats exhibited higher basal levels of reactive oxygen species (ROS) and higher mitochondrial membrane potential, demonstrating that the PT cells maintain the diabetic phenotype in primary culture. Incubation with either the oxidants or mitochondrial toxicant resulted in greater necrotic and apoptotic cell death, greater evidence of morphological damage, greater increases in ROS, and greater decreases in mitochondrial membrane potential in PT cells from diabetic rats than in those from control rats. Pretreatment with either the antioxidant N-acetyl-L-cysteine or a catalase mimetic provided equivalent protection of PT cells from both diabetic and control rats. Despite the greater susceptibility to oxidative and mitochondrial injury, both cytoplasmic and mitochondrial glutathione concentrations were markedly higher in PT cells from diabetic rats, suggesting an upregulation of antioxidant processes in diabetic kidney. These results support the hypothesis that primary cultures of PT cells from diabetic rats are a valid model in which to study renal cellular function in the diabetic state.

  14. Activation of PPARα by Oral Clofibrate Increases Renal Fatty Acid Oxidation in Developing Pigs.

    Science.gov (United States)

    He, Yonghui; Khan, Imad; Bai, Xiumei; Odle, Jack; Xi, Lin

    2017-12-08

    The objective of this study was to evaluate the effects of peroxisome proliferator-activated receptor α (PPARα) activation by clofibrate on both mitochondrial and peroxisomal fatty acid oxidation in the developing kidney. Ten newborn pigs from 5 litters were randomly assigned to two groups and fed either 5 mL of a control vehicle (2% Tween 80) or a vehicle containing clofibrate (75 mg/kg body weight, treatment). The pigs received oral gavage daily for three days. In vitro fatty acid oxidation was then measured in kidneys with and without mitochondria inhibitors (antimycin A and rotenone) using [1- 14 C]-labeled oleic acid (C18:1) and erucic acid (C22:1) as substrates. Clofibrate significantly stimulated C18:1 and C22:1 oxidation in mitochondria ( p oxidation rate of C18:1 was greater in mitochondria than peroxisomes, while the oxidation of C22:1 was higher in peroxisomes than mitochondria ( p oxidation, the mRNA abundance and enzyme activity of carnitine palmitoyltransferase I (CPT I) in mitochondria were increased. Although mRNA of mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase (mHMGCS) was increased, the β-hydroxybutyrate concentration measured in kidneys did not increase in pigs treated with clofibrate. These findings indicate that PPARα activation stimulates renal fatty acid oxidation but not ketogenesis.

  15. Activation of PPARα by Oral Clofibrate Increases Renal Fatty Acid Oxidation in Developing Pigs

    Directory of Open Access Journals (Sweden)

    Yonghui He

    2017-12-01

    Full Text Available The objective of this study was to evaluate the effects of peroxisome proliferator-activated receptor α (PPARα activation by clofibrate on both mitochondrial and peroxisomal fatty acid oxidation in the developing kidney. Ten newborn pigs from 5 litters were randomly assigned to two groups and fed either 5 mL of a control vehicle (2% Tween 80 or a vehicle containing clofibrate (75 mg/kg body weight, treatment. The pigs received oral gavage daily for three days. In vitro fatty acid oxidation was then measured in kidneys with and without mitochondria inhibitors (antimycin A and rotenone using [1-14C]-labeled oleic acid (C18:1 and erucic acid (C22:1 as substrates. Clofibrate significantly stimulated C18:1 and C22:1 oxidation in mitochondria (p < 0.001 but not in peroxisomes. In addition, the oxidation rate of C18:1 was greater in mitochondria than peroxisomes, while the oxidation of C22:1 was higher in peroxisomes than mitochondria (p < 0.001. Consistent with the increase in fatty acid oxidation, the mRNA abundance and enzyme activity of carnitine palmitoyltransferase I (CPT I in mitochondria were increased. Although mRNA of mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase (mHMGCS was increased, the β-hydroxybutyrate concentration measured in kidneys did not increase in pigs treated with clofibrate. These findings indicate that PPARα activation stimulates renal fatty acid oxidation but not ketogenesis.

  16. The role of mitochondria for the regulation of cardiac alternans

    Directory of Open Access Journals (Sweden)

    Stela M Florea

    2010-11-01

    Full Text Available Electromechanical and Ca alternans is a beat-to-beat alternation of action potential duration, contraction strength and Ca transient amplitude observed in cardiac myocytes at regular stimulation frequency. Ca alternans is a multifactorial process that is causally linked to cardiac arrhythmias. At the cellular level, conditions that increase fractional release from the sarcoplasmic reticulum or reduce diastolic Ca sequestration favor the occurrence of alternans. Mitochondria play a significant role in cardiac excitation-contraction coupling and Ca signaling by providing the energy for contraction and ATP-dependent processes and possibly by serving as Ca buffering organelles. Here we tested the hypothesis that impairment of mitochondrial function generates conditions that favor the occurrence of Ca alternans. Alternans were elicited by electrical pacing (>1 Hz in single cat atrial myocytes and intracellular Ca ([Ca]i was measured with the fluorescent Ca indicator Indo-1. The degree of alternans was quantified as the alternans ratio (AR=1-S/L, where S/L is the ratio of the small to the large amplitude of a pair of alternating Ca transients. Dissipation of mitochondrial membrane potential (with FCCP as well as inhibition of mitochondrial F1/F0-ATP synthase (oligomycin, electrontransport chain (rotenone, antimycin, CN-, Ca-dependent dehydrogenases and mitochondrial Ca uptake or extrusion, all enhanced AR and lowered the threshold for the occurrence of Ca alternans. The data indicate that impairment of mitochondrial function adversely affects cardiac Ca cycling leading to proarrhythmic Ca alternans.

  17. Mitochondrial Swelling Induced by Glutathione

    Science.gov (United States)

    Lehninger, Albert L.; Schneider, Marion

    1959-01-01

    Reduced glutathione, in concentrations approximating those occurring in intact rat liver, causes swelling of rat liver mitochondria in vitro which is different in kinetics and extent from that yielded by L-thyroxine. The effect is also given by cysteine, which is more active, and reduced coenzyme A, but not by L-ascorbate, cystine, or oxidized glutathione. The optimum pH is 6.5, whereas thyroxine-induced swelling is optimal at pH 7.5. The GSH-induced swelling is not inhibited by DNP or dicumarol, nor by high concentrations of sucrose, serum albumin, or polyvinylpyrrolidone, in contrast to thyroxine-induced swelling. ATP inhibits the GSH swelling, but ADP and AMP are ineffective. Mn-+ is a very potent inhibitor, but Mg++ is ineffective. Ethylenediaminetetraacetate is also an effective inhibitor of GSH-induced swelling. The respiratory inhibitors amytal and antimycin A do not inhibit the swelling action of GSH, but cyanide does; these findings are consistent with the view that the oxidation-reduction state of the respiratory chain between cytochrome c and oxygen is a determinant of GSH-induced swelling. Reversal of GSH-induced swelling by osmotic means or by ATP in KCl media could not be observed. Large losses of nucleotides and protein occur during the swelling by GSH, suggesting that the action is irreversible. The characteristically drastic swelling action of GSH could be prevented if L-thyroxine was also present in the medium. PMID:13630941

  18. Intracellular localization of phosphatidylcholine and phosphatidylethanolamine synthesis in cotyledons of cotton seedlings

    International Nuclear Information System (INIS)

    Chapman, K.D.; Trelease, R.N.

    1991-01-01

    Subfractionation of clarified cotyledon homogenates of cotton (Gossypium hirsutum L.) seedlings on sucrose gradients revealed a single coincident peak of cholinephosphotransferase (CPT) and ethanolaminephosphotransferase (EPT) activities, which equilibrated with the main peak of Anti-mycin A-insensitive NADH: cytochrome c reductase (CCR) activity. The small percentage of CPT and EPT activities in glyoxysome-enriched pellets equilibrated with cytochrome c oxidase activity, not with catalase activity. Preincubation of microsomes in 0.2 millimolar MgCl 2 followed by subfractionation on sucrose gradients resulted in peak CPT and EPT activities equilibrating with peak CCR activity at 24% (w/w) sucrose. Preincubation of microsomes with 14 C-CCP choline (or 14 C-CDPethanolamine) resulted in synthesis and incorporation of 14 C-phosphatidylcholine (PC) (or 14 C-phosphatidylethanolamine, PE) into membranes at the same density. Increasing the Mg 2+ concentration to 2.0 millimolar facilitated binding of ribosomes and caused a concomitant shift in density (to 34% w/w sucrose) of peak CPT, EPT, and CCR activities. under these conditions, newly synthesized and incorporated 14 C-PC (or PE) was recovered in these membranes. These results indicate that Er in cotyledons of germinated cotton seedlings is the primary subcellular site of PC and PE synthesis. This is similar to the situation in endosperm tissue but distinctly different from root and hypocotyl tissue where Golgi are a major subcellular site of PC and PE synthesis

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

    International Nuclear Information System (INIS)

    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 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. 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 14 C-butyl gallate. Plant mitochondria in which cyanide-resistance was induced bound as much 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 5 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

  20. 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

  1. Unsaturated fatty acids-dependent linkage between respiration and fermentation revealed by deletion of hypoxic regulatory KlMGA2 gene in the facultative anaerobe-respiratory yeast Kluyveromyces lactis.

    Science.gov (United States)

    Ottaviano, Daniela; Montanari, Arianna; De Angelis, Lorenzo; Santomartino, Rosa; Visca, Andrea; Brambilla, Luca; Rinaldi, Teresa; Bello, Cristiano; Reverberi, Massimo; Bianchi, Michele M

    2015-08-01

    In the yeast Kluyveromyces lactis, the inactivation of structural or regulatory glycolytic and fermentative genes generates obligate respiratory mutants which can be characterized by sensitivity to the mitochondrial drug antimycin A on glucose medium (Rag(-) phenotype). Rag(-) mutations can occasionally be generated by the inactivation of genes not evidently related to glycolysis or fermentation. One such gene is the hypoxic regulatory gene KlMGA2. In this work, we report a study of the many defects, in addition to the Rag(-) phenotype, generated by KlMGA2 deletion. We analyzed the fermentative and respiratory metabolism, mitochondrial functioning and morphology in the Klmga2Δ strain. We also examined alterations in the regulation of the expression of lipid biosynthetic genes, in particular fatty acids, ergosterol and cardiolipin, under hypoxic and cold stress and the phenotypic suppression by unsaturated fatty acids of the deleted strain. Results indicate that, despite the fact that the deleted mutant strain had a typical glycolytic/fermentative phenotype and KlMGA2 is a hypoxic regulatory gene, the deletion of this gene generated defects linked to mitochondrial functions suggesting new roles of this protein in the general regulation and cellular fitness of K. lactis. Supplementation of unsaturated fatty acids suppressed or modified these defects suggesting that KlMga2 modulates membrane functioning or membrane-associated functions, both cytoplasmic and mitochondrial. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Biochemical factors affecting the quantum efficiency of hydrogen production by membranes of green photosynthetic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, J.D.; Olson, J.M.

    1981-01-01

    Photohydrogen production, 200-700 ..mu..mol H/sub 2/ h/sup -1/ (mg bacteriochlorophyll a)/sup -1/ has been obtained in a system containing unit membrane vesicles (Complex I) from the green photosynthetic bacterium Chlorobium limicola f. thiosulfatophilum, ascorbate, N,N,N',N'-tetramethyl-p-phenylenediamine, dithioerythritol, an oxygen scavenging mixture, either methyl viologen (MV) or clostridial ferredoxin (CPS Fd) as electron carrier, and either CPS hydrogenase or platinum asbestos as catalyst. All components are necessary for maximum activity, and spinach Fd cannot be substituted for CPS Fd. Higher rates of photohydrogen production are obtained using MV or CPS Fd with hydrogenase than with MV and Pt asbestos. The highest quantum efficiencies (7-10% at 0.2-0.9 mW absorbed light and over 20% at lower light) were obtained with CPS Fd, hydrogenase and non-saturating 812 nm light. With saturating white light, however, rates of photohydrogen production varied relatively little among the various combinations of electron carrier and catalyst tested. The reaction rate is unaffected by 0.03% Triton X-100, and is insensitive to treatment with antimycin a or m-chloro-carbonyl cyanide phenylhydrazone.This indicates that neither electron flow through an endogenous cyclic chain, nor maintenance of a proton gradient are involved in this process.

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

    Energy Technology Data Exchange (ETDEWEB)

    Polgari, Zs. [Eoetvoes Lorand University, Institute of Chemistry, Department of Analytical Chemistry, Laboratory of Environmental Chemistry and Bioanalytics, P.O. Box 32, H-1518, Budapest (Hungary); Meirer, F. [Institute of Atomic and Subatomic Physics, Vienna University of Technology, Vienna (Austria); MiNALab, CMM-irst, Fondazione Bruno Kessler, Povo, Trento (Italy); Sasamori, S.; Ingerle, D. [Institute of Atomic and Subatomic Physics, Vienna University of Technology, Vienna (Austria); Pepponi, G. [MiNALab, CMM-irst, Fondazione Bruno Kessler, Povo, Trento (Italy); Streli, C. [Institute of Atomic and Subatomic Physics, Vienna University of Technology, Vienna (Austria); Rickers, K. [Hamburger Synchrotronstrahlungslabor at DESY, Hamburg (Germany); Reti, A.; Budai, B. [Department of Clinical Research, National Institute of Oncology, Budapest (Hungary); Szoboszlai, N. [Eoetvoes Lorand University, Institute of Chemistry, Department of Analytical Chemistry, Laboratory of Environmental Chemistry and Bioanalytics, P.O. Box 32, H-1518, Budapest (Hungary); Zaray, G., E-mail: zaray@ludens.elte.hu [Eoetvoes Lorand University, Institute of Chemistry, Department of Analytical Chemistry, Laboratory of Environmental Chemistry and Bioanalytics, P.O. Box 32, H-1518, Budapest (Hungary)

    2011-03-15

    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{sub 2} or NiCl{sub 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-{alpha},{alpha}'-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.

  4. The enhancement of cyclic electron flow around photosystem I improves the recovery of severely desiccated Porphyra yezoensis (Bangiales, Rhodophyta).

    Science.gov (United States)

    Gao, Shan; Wang, Guangce

    2012-07-01

    Porphyra yezoensis, a representative species of intertidal macro-algae, is able to withstand periodic desiccation at low tide but is submerged in seawater at high tide. In this study, changes in photosynthetic electron flow in P. yezoensis during desiccation and re-hydration were investigated. The results suggested that the cyclic electron flow around photosystem I (PSI) increased significantly during desiccation, continued to operate at times of severe desiccation, and showed greater tolerance to desiccation than the electron flow around PSII. In addition, PSI activity in desiccated blades recovered faster than PSII activity during re-hydration. Even though linear electron flow was suppressed by DCMU [3-(3',4'-dichlorophenyl)-1,1-dimethylurea], cyclic electron flow could still be restored. This process was insensitive to antimycin A and could be suppressed by dibromothymoquinone (DBMIB). The prolonged dark treatment of blades reduced the speed in which the cyclic electron flow around PSI recovered, suggesting that stromal reductants, including NAD(P)H, played an important role in the donation of electrons to PSI and were the main cause of the rapid recovery of cyclic electron flow in desiccated blades during re-hydration. These results suggested that cyclic electron flow in P. yezoensis played a significant physiological role during desiccation and re-hydration and may be one of the most important factors allowing P. yezoensis blades to adapt to intertidal environments.

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

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, K.M.; Boehme, M.; Inbar, O.

    1982-10-01

    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 /sup 125/I-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.

  6. Ascorbate Biosynthesis in Mitochondria Is Linked to the Electron Transport Chain between Complexes III and IV1

    Science.gov (United States)

    Bartoli, Carlos G.; Pastori, Gabriela M.; Foyer, Christine H.

    2000-01-01

    Ascorbic acid is synthesized from galactono-γ-lactone (GL) in plant tissues. An improved extraction procedure involving ammonium sulfate precipitation of membrane proteins from crude leaf homogenates yielded a simple, quick method for determining tissue activities of galactono-γ-lactone dehydrogenase (GLDH). Total foliar ascorbate and GLDH activity decreased with leaf age. Subcellular fractionation experiments using marker enzymes demonstrated that 80% of the total GLDH activity was located on the inner mitochondrial membrane, and 20% in the microsomal fraction. Specific antibody raised against potato (Solanum tuberosum L.) tuber GLDH recognized a 56-kD polypeptide in extracts from the mitochondrial membranes but failed to detect the equivalent polypeptide in microsomes. We demonstrate that isolated intact mitochondria synthesize ascorbate in the presence of GL. GL stimulated mitochondrial electron transport rates. The respiration inhibitor antimycin A stimulated ascorbate biosynthesis, while cyanide inhibited both respiration and ascorbate production. GL-dependent oxygen uptake was observed in isolated intact mitochondria. This evidence suggests that GLDH delivers electrons to the mitochondrial electron transport chain between complexes III and IV. PMID:10806250

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

    International Nuclear Information System (INIS)

    Xu Qiuwei; Vu, Heather; Liu Liping; Wang, Ting-Chuan; Schaefer, William H.

    2011-01-01

    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.

  8. 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.

  9. Mitochondrial respiratory pathways inhibition in Rhizopus oryzae potentiates activity of posaconazole and itraconazole via apoptosis.

    Directory of Open Access Journals (Sweden)

    Fazal Shirazi

    Full Text Available The incidence of mucormycosis has increased drastically in immunocompromised patients. Also the array of targets whose inhibition results in Mucorales death is limited. Recently, researchers identified mitochondria as important regulators of detoxification and virulence mechanisms in fungi. In this context, targeting the mitochondrial respiratory chain may provide a new platform for antifungal development. We hypothesized that targeting respiratory pathways potentiates triazoles activity via apoptosis. We found that simultaneous administration of antimycin A (AA and benzohydroxamate (BHAM, inhibitors of classical and alternative mitochondrial pathways respectively, resulted in potent activity of posaconazole (PCZ and itraconazole (ICZ against Rhizopus oryzae. We observed cellular changes characteristic of apoptosis in R. oryzae cells treated with PCZ or ICZ in combination with AA and BHAM. The fungicidal activity of this combination against R. oryzae was correlated with intracellular reactive oxygen species accumulation (ROS, phosphatidylserine externalization, mitochondrial membrane depolarization, and increased caspase like activity. DNA fragmentation and condensation assays also revealed apoptosis of R. oryzae cells. These apoptotic features were prevented by the addition of the ROS scavenger N-acetyl-cysteine. Taken together, these findings suggest that the use of PCZ or ICZ in combination with AA and BHAM makes R. oryzae exquisitely sensitive to treatment with triazoles via apoptosis. This strategy may serve as a new model for the development of improved or novel antifungal agents.

  10. Mechanism of triclosan toxicity: Mitochondrial dysfunction including complex II inhibition, superoxide release and uncoupling of oxidative phosphorylation.

    Science.gov (United States)

    Teplova, Vera V; Belosludtsev, Konstantin N; Kruglov, Alexey G

    2017-06-05

    Triclosan (5-chloro-2'-(2,4-dichlorophenoxy)phenol), a widely used antibacterial agent, exerts adverse effects on the organism of mammals. Recent research reviled that triclosan at low micromolar concentrations causes mitochondrial dysfunction in many cell types, but the mechanisms of its effect are not fully understood. Here we show that exposure to triclosan disrupted membrane potential, prevented the calcium uptake-driven high-amplitude mitochondrial swelling, stimulated the respiration in the presence of complex I substrates, and suppressed the ADP-stimulated respiration in the presence of complex II substrate, succinate. Triclosan directly inhibited complex II activity. Similar to the complex II inhibitor thenoyltrifluoroacetone, triclosan induced the oxidation of the cytochromes b566 and b562 and caused the release of mitochondrial superoxide. Opposite to thenoyltrifluoroacetone, triclosan increased superoxide release synergistically with myxothiazol but not with antimycin A, indicating different topology of superoxide-producing sites. We concluded that triclosan is unique by its capability of acting as both a protonophore and an unusual complex II inhibitor, which interferes with the mitochondrial respiration by blocking the electron transfer between ubiquinone at the Q d -binding site and heme b. Our data can provide an insight into the mechanisms of the carcinogenic effect of triclosan in the liver and other tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

    Arechederra, Marguerite N.; Fischer, Caitlin N.; Wetzel, David J.; Minteer, Shelley D.

    2010-01-01

    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.

  12. Mitochondrial Respiratory Pathways Inhibition in Rhizopus oryzae Potentiates Activity of Posaconazole and Itraconazole via Apoptosis

    Science.gov (United States)

    Shirazi, Fazal; Kontoyiannis, Dimitrios P.

    2013-01-01

    The incidence of mucormycosis has increased drastically in immunocompromised patients. Also the array of targets whose inhibition results in Mucorales death is limited. Recently, researchers identified mitochondria as important regulators of detoxification and virulence mechanisms in fungi. In this context, targeting the mitochondrial respiratory chain may provide a new platform for antifungal development. We hypothesized that targeting respiratory pathways potentiates triazoles activity via apoptosis. We found that simultaneous administration of antimycin A (AA) and benzohydroxamate (BHAM), inhibitors of classical and alternative mitochondrial pathways respectively, resulted in potent activity of posaconazole (PCZ) and itraconazole (ICZ) against Rhizopus oryzae. We observed cellular changes characteristic of apoptosis in R. oryzae cells treated with PCZ or ICZ in combination with AA and BHAM. The fungicidal activity of this combination against R. oryzae was correlated with intracellular reactive oxygen species accumulation (ROS), phosphatidylserine externalization, mitochondrial membrane depolarization, and increased caspase like activity. DNA fragmentation and condensation assays also revealed apoptosis of R. oryzae cells. These apoptotic features were prevented by the addition of the ROS scavenger N-acetyl-cysteine. Taken together, these findings suggest that the use of PCZ or ICZ in combination with AA and BHAM makes R. oryzae exquisitely sensitive to treatment with triazoles via apoptosis. This strategy may serve as a new model for the development of improved or novel antifungal agents. PMID:23696824

  13. Effects of chitosan and oligochitosan on development and mitochondrial function of Rhizopus stolonifer.

    Science.gov (United States)

    Robles-Martínez, Leobarda; Guerra-Sánchez, María Guadalupe; Hernández-Lauzardo, Ana Niurka; Pardo, Juan Pablo; Velázquez-del Valle, Miguel Gerardo

    2014-07-01

    The antifungal activities of chitosan and oligochitosan have been used to control postharvest decay of the fruits. The effect of chitosan and oligochitosan on mycelium growth, spore germination, and mitochondrial function of Rhizopus stolonifer was evaluated in order to establish a connection between fungus development and the main organelle in charge to provide energy to the cell. The mycelium growth of R. stolonifer was significantly reduced on minimum media amended with chitosan or oligochitosan. The highest antifungal indexes were obtained on media containing chitosan or oligochitosan at 2.0 mg ml(-1). Microscopic observation showed that chitosan and oligochitosan affected the spore germination and hyphae morphology. Both polymers increased oxygen consumption of R. stolonifer. Respiratory activity was restored with NADH in permeabilized treated and untreated cells, and was inhibited with rotenone and flavones. Complex III and IV were inhibited by antimycin A and cyanide, respectively, in treated and untreated cells. Chitosan and oligochitosan increased NADH dehydrogenase activity in isolated mitochondria. However, there were not changes in the cytochrome c oxidase and ATPase activities by effect of these polymers. These results suggest that both chitosan and oligochitosan affect the development of R. stolonifer and might be implicated in the mitochondrial dysfunction. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Endocytosis of heat-denatured albumin by cultured rat Kupffer cells

    International Nuclear Information System (INIS)

    Brouwer, A.; Knook, D.L.

    1982-01-01

    Purified Kupffer cells were obtained by centrifugal elutriation of sinusoidal cells isolated by pronase treatment of the rat liver. The endocytosis of radioactively labeled heat-aggregated colloidal albumin (CA 125 I) was investigated in maintenance cultures of the purified Kupffer cells. The endocytic capacity of the cells was studied during 4 days of culture. Maximum uptake was observed after 24 hr of culture, with a gradual decline during the following days. When the uptake was measured after incubation with increasing concentrations of CA 125 I, a saturation effect was observed. This finding and the observed high rate of uptake are strong indications that receptor sites on the cell membrane are involved in the mechanism of endocytosis. The uptake of CA 125 I by Kupffer cells was inhibited by the metabolic inhibitors fluoride and antimycin A, indicating that endocytosis of CA 125 I is dependent on energy derived from both glycolysis and mitochondrial respiration. The mechanism of internalization may also require the action of microfilaments as well as intact microtubules, since both cytochalasin B and colchicine inhibited the uptake of CA 125 I. The intracellular degradation of CA 125 I by Kupffer cells was strongly inhibited by chloroquine but not by colchicine. The degradation of ingested CA 125 I occurred within the Kupffer cell lysosomes

  15. Piscicides and invertebrates: after 70 years, does anyone really know?

    Science.gov (United States)

    Vinson, M.R.; Dinger, E.C.; Vinson, D.K.

    2010-01-01

    The piscicides rotenone and antimycin have been used for more than 70 years to manage fish populations by eliminating undesirable fish species. The effects of piscicides on aquatic invertebrate assemblages are considered negligible by some and significant by others. This difference of opinion has created contentious situations and delayed native fish restoration projects. We review the scientific evidence and report that short-term ( 1 year) impacts are largely unknown. Recovery of invertebrate assemblages following treatments ranged from a few months for abundances of common taxa to several years for rarer taxa. Variation in reported effects was primarily due to natural variation among species and habitats and a lack of adequate pre- and post-treatment sampling which prevents determining the true impacts to invertebrate assemblages. The factors most likely to influence impacts and recovery of aquatic invertebrate assemblages following piscicide treatments are: (1) concentration, duration, and breadth of the piscicide treatment; (2) invertebrate morphology and life history characteristics, including surface area to volume ratios, type of respiration organs, generation time, and propensity to disperse; (3) refugia presence; and (4) distance from colonization sources.

  16. The Superoxide Synthases of Plasma Membrane Preparations from Cultured Rose Cells.

    Science.gov (United States)

    Murphy, T. M.; Auh, C. K.

    1996-01-01

    Preparations of plasma membranes isolated from cultured rose (Rosa damascena Mill. cv Gloire de Guilan) cells synthesized O2- when incubated with either NADH or NADPH, as measured by an O2--specific assay based on the chemiluminescence of lucigenin. The activities were strongly dependent on the presence of Triton X-100. The Km for NADH was 159 [mu]M; that for NADPH was 19 [mu]M. Neither NADH- nor NADPH-dependent activity was inhibited by azide, an inhibitor of peroxidase, nor by antimycin A, an inhibitor of mitochondrial electron transport; both activities were inhibited by 30 to 100 nM diphenylene iodonium, an inhibitor of the mammalian NADPH oxidase. The NADH- and NADPH-dependent activities could be distinguished by detergent solubilization and ultracentrifugation: the NADH-dependent activity sedimented more easily, whereas the NADPH-dependent activity remained in suspension. One or both of these enzymes may provide the O2- seen when plant cells are exposed to pathogens or pathogen-associated elicitors; however, plasma membranes from rose cells treated with a Phytophthora elicitor had the same activity as control cells. PMID:12226208

  17. The relationship between energy metabolism and the action of inhibitors of histamine release

    DEFF Research Database (Denmark)

    Garland, L G; Johansen, Torben

    1977-01-01

    1 Dextran-induced release of histamine from rat mast cells was inhibited equally in complete and glucose-free Tyrode solution by doxantrazole (0.03-3 micronmol/l), theophylline (0.1-3 mmol/l) and dicumarol (0.01-10 micronmol/litre). 2 Doxantrazole (3 micronmol/l), theophylline (3 mmol/l) and dicu......1 Dextran-induced release of histamine from rat mast cells was inhibited equally in complete and glucose-free Tyrode solution by doxantrazole (0.03-3 micronmol/l), theophylline (0.1-3 mmol/l) and dicumarol (0.01-10 micronmol/litre). 2 Doxantrazole (3 micronmol/l), theophylline (3 mmol...... of histamine release from mast cells incubated in glucose-free solution than in complete Tyrode solution (dose-ratio = 20). Like antimycin A (L MICRONMOL/L), PAPAVERINE (3 MICRONMOL/L) CAUSED A DEPLETION OF MAST CELL ATP that was greater in the absence (85%) than in the presence (25%) of extracellular glucose....... 4 These results suggest that dicumarol, like doxantrazole and theophylline, inhibits histamine release without affecting mast cell energy metabolism. In contrast, papaverine probably inhibits release by depleting ATP that is required for exocytosis. 5 Inhibition of histamine release by dibutyryl...

  18. Inhibitor-induced oxidation of the nucleus and cytosol in Arabidopsis thaliana: implications for organelle to nucleus retrograde signalling.

    Science.gov (United States)

    Karpinska, Barbara; Alomrani, Sarah Owdah; Foyer, Christine H

    2017-09-26

    Concepts of organelle-to-nucleus signalling pathways are largely based on genetic screens involving inhibitors of chloroplast and mitochondrial functions such as norflurazon, lincomycin (LINC), antimycin A (ANT) and salicylhydroxamic acid. These inhibitors favour enhanced cellular oxidation, but their precise effects on the cellular redox state are unknown. Using the in vivo reduction-oxidation (redox) reporter, roGFP2, inhibitor-induced changes in the glutathione redox potentials of the nuclei and cytosol were measured in Arabidopsis thaliana root, epidermal and stomatal guard cells, together with the expression of nuclear-encoded chloroplast and mitochondrial marker genes. All the chloroplast and mitochondrial inhibitors increased the degree of oxidation in the nuclei and cytosol. However, inhibitor-induced oxidation was less marked in stomatal guard cells than in epidermal or root cells. Moreover, LINC and ANT caused a greater oxidation of guard cell nuclei than the cytosol. Chloroplast and mitochondrial inhibitors significantly decreased the abundance of LHCA1 and LHCB1 transcripts. The levels of WHY1 , WHY3 and LEA5 transcripts were increased in the presence of inhibitors. Chloroplast inhibitors decreased AOXA1 mRNA levels, while mitochondrial inhibitors had the opposite effect. Inhibitors that are used to characterize retrograde signalling pathways therefore have similar general effects on cellular redox state and gene expression.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Authors.

  19. Growth of Streptococcus faecalis var. zymogenes on glycerol: the effect of aerobic and anaerobic growth in the presence and absence of haematin on enzyme synthesis.

    Science.gov (United States)

    Pugh, S Y; Knowles, C J

    1982-05-01

    Streptococcus faecalis var. zymogenes was grown aerobically and anaerobically in the presence and absence of haematin, with glycerol as the carbon and energy source. Aerobic growth was stimulated by the inclusion of haematin in the medium but fumarate had no effect on growth. The bacterium was unable to grow anaerobically on glycerol unless fumarate was present; haematin had no effect on growth. NADH oxidase activity, which catalysed the oxidation of NADH + H+ to form H2O rather than H2O2, was found in the soluble fraction and was induced by aerobic growth but partially repressed when haematin was present in the medium. In contrast, a particulate NADH oxidase, which was sensitive to inhibition by antimycin A and 2-heptyl-4-hydroxyquinoline N-oxide, was induced by aerobic growth in the presence of haematin. NADH peroxidase was massively induced by aerobic growth, whereas more lactate dehydrogenase activity was found in anaerobically grown bacteria. Catalase was formed only during aerobic growth in the presence of haematin.

  20. Effects of mitochondrial poisons on glutathione redox potential and carotid body chemoreceptor activity.

    Science.gov (United States)

    Gomez-Niño, A; Agapito, M T; Obeso, A; Gonzalez, C

    2009-01-01

    Low oxygen sensing in chemoreceptor cells involves the inhibition of specific plasma membrane K(+) channels, suggesting that mitochondria-derived reactive oxygen species (ROS) link hypoxia to K(+) channel inhibition, subsequent cell depolarization and activation of neurotransmitter release. We have used several mitochondrial poisons, alone and in combination with the antioxidant N-acetylcysteine (NAC), and quantify their capacity to alter GSH/GSSG levels and glutathione redox potential (E(GSH)) in rat diaphragm. Selected concentrations of mitochondrial poisons with or without NAC were tested for their capacity to activate neurotransmitter release in chemoreceptor cells and to alter ATP levels in intact rat carotid body (CB). We found that rotenone (1 microM), antimycin A (0.2 microg/ml) and sodium azide (5mM) decreased E(GSH); NAC restored E(GSH) to control values. At those concentrations mitochondrial poisons activated neurotransmitter release from CB chemoreceptor cells and decreased CB ATP levels, NAC being ineffective to modify these responses. Additional experiments with 3-nitroprionate (5mM), lower concentrations of rotenone and dinitrophenol revealed variable relationships between E(GSH) and chemoreceptor cell neurotransmitter release responses and ATP levels. These findings indicate a lack of correlation between mitochondrial-generated modifications of E(GSH) and chemoreceptor cells activity. This lack of correlation renders unlikely that alteration of mitochondrial production of ROS is the physiological pathway chemoreceptor cells use to signal hypoxia.

  1. Role of Mitochondrial Electron Transport Chain Dysfunction in Cr(VI-Induced Cytotoxicity in L-02 Hepatocytes

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    Fang Xiao

    2014-04-01

    Full Text Available Background: Hexavalent chromium [Cr(VI] and its compounds (e.g. chromates, which are extensively used in numerous industrial processes including leather tanning and steel manufacturing, are considered as priority pollutants. There is growing evidence supporting that Cr(VI could be a human carcinogen that induces primary liver cancer after oral exposure, and this sheds light on the importance of the investigation of Cr(VI-induced hepatotoxicity. Although it is known that mitochondria are major targets for heavy metals, the mechanisms of electron transfer chain (ETC dysfunction involved in Cr(VI-induced cytotoxicity are unclear. Methods: In the present study, by using mitochondrial respiratory chain complex (MRCC I inhibitor rotenone (ROT and its substrates glutamate/malate (Glu/Mal, MRCC III inhibitor antimycin A (AA and its substrate coenzyme Q (CoQ, and the antioxidant Vitamin C (Vit C, we aimed to elucidate the role of mitochondrial ETC dysfunction in Cr(VI-induced cytotoxicity. Results: We found that Cr(VI targeted and inhibited MRCC I and III to induce ETC dysfunction, which played an important role in Cr(VI-induced cytotoxicity. Conclusion: Our current data provides novel important insight into the mechanisms of mitochondrial ETC dysfunction in Cr(VI-induced cytotoxicity in the hepatocytes, and we will be poised to develop new methods in the prevention and treatment of liver diseases involving mitochondrial ETC dysfunction for the occupational exposure population.

  2. 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.

  3. Generation of adenosine tri-phosphate in Leishmania donovani amastigote forms.

    Science.gov (United States)

    Mondal, Subhasish; Roy, Jay Jyoti; Bera, Tanmoy

    2014-03-01

    Leishmania, the causative agent of various forms of leishmaniasis, is the significant cause of morbidity and mortality. 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. We carried out the study of susceptibilities to different inhibitors of mitochondrial electron transport chain and studies on substrate level phosphorylation in wild-type L. donovani. The amastigote forms of L. donovani are independent on oxidative phosphorylation for ATP production. Indeed, its cell growth was not inhibited by excess oligomycin and dicyclohexylcarbodiimide, which are the most specific inhibitors of the mitochondrial Fo/F1-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 in amastigotes whereas NADH-fumarate and NADH-pyruvate couples failed to produce ATP. In contrast, NADPH-fumarate showed the highest rate of ATP formation in promastigotes. Therefore, we can conclude that substrate level phosphorylation is essential for the survival of amastigote forms of Leishmania donovani.

  4. 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.

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

    Science.gov (United States)

    Collins, N; Merrett, M J

    1975-01-01

    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

  6. Quinol-cytochrome c Oxidoreductase and Cytochrome c4 Mediate Electron Transfer during Selenate Respiration in Thauera selenatis*

    Science.gov (United States)

    Lowe, Elisabeth C.; Bydder, Sarah; Hartshorne, Robert S.; Tape, Hannah L. U.; Dridge, Elizabeth J.; Debieux, Charles M.; Paszkiewicz, Konrad; Singleton, Ian; Lewis, Richard J.; Santini, Joanne M.; Richardson, David J.; Butler, Clive S.

    2010-01-01

    Selenate reductase (SER) from Thauera selenatis is a periplasmic enzyme that has been classified as a type II molybdoenzyme. The enzyme comprises three subunits SerABC, where SerC is an unusual b-heme cytochrome. In the present work the spectropotentiometric characterization of the SerC component and the identification of redox partners to SER are reported. The mid-point redox potential of the b-heme was determined by optical titration (Em + 234 ± 10 mV). A profile of periplasmic c-type cytochromes expressed in T. selenatis under selenate respiring conditions was undertaken. Two c-type cytochromes were purified (∼24 and ∼6 kDa), and the 24-kDa protein (cytc-Ts4) was shown to donate electrons to SerABC in vitro. Protein sequence of cytc-Ts4 was obtained by N-terminal sequencing and liquid chromatography-tandem mass spectrometry analysis, and based upon sequence similarities, was assigned as a member of cytochrome c4 family. Redox potentiometry, combined with UV-visible spectroscopy, showed that cytc-Ts4 is a diheme cytochrome with a redox potential of +282 ± 10 mV, and both hemes are predicted to have His-Met ligation. To identify the membrane-bound electron donors to cytc-Ts4, growth of T. selenatis in the presence of respiratory inhibitors was monitored. The specific quinol-cytochrome c oxidoreductase (QCR) inhibitors myxothiazol and antimycin A partially inhibited selenate respiration, demonstrating that some electron flux is via the QCR. Electron transfer via a QCR and a diheme cytochrome c4 is a novel route for a member of the DMSO reductase family of molybdoenzymes. PMID:20388716

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

    International Nuclear Information System (INIS)

    Forquer, Isaac P.; Covian, Raul; Bowman, Michael K.; Trumpower, Bernard; Kramer, David M.

    2006-01-01

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Reconstitution of the anti-apoptotic Bcl-2 protein into lipid membranes and biophysical evidence for its detergent-driven association with the pro-apoptotic Bax protein.

    Directory of Open Access Journals (Sweden)

    Marcus Wallgren

    Full Text Available The anti-apoptotic B-cell CLL/lymphoma-2 (Bcl-2 protein and its counterpart, the pro-apoptotic Bcl-2-associated X protein (Bax, are key players in the regulation of the mitochondrial pathway of apoptosis. However, how they interact at the mitochondrial outer membrane (MOM and there determine whether the cell will live or be sentenced to death remains unknown. Competing models have been presented that describe how Bcl-2 inhibits the cell-killing activity of Bax, which is common in treatment-resistant tumors where Bcl-2 is overexpressed. Some studies suggest that Bcl-2 binds directly to and sequesters Bax, while others suggest an indirect process whereby Bcl-2 blocks BH3-only proteins and prevents them from activating Bax. Here we present the results of a biophysical study in which we investigated the putative interaction of solubilized full-length human Bcl-2 with Bax and the scope for incorporating the former into a native-like lipid environment. Far-UV circular dichroism (CD spectroscopy was used to detect direct Bcl-2-Bax-interactions in the presence of polyoxyethylene-(23-lauryl-ether (Brij-35 detergent at a level below its critical micelle concentration (CMC. Additional surface plasmon resonance (SPR measurements confirmed this observation and revealed a high affinity between the Bax and Bcl-2 proteins. Upon formation of this protein-protein complex, Bax also prevented the binding of antimycin A2 (a known inhibitory ligand of Bcl-2 to the Bcl-2 protein, as fluorescence spectroscopy experiments showed. In addition, Bcl-2 was able to form mixed micelles with Triton X-100 solubilized neutral phospholipids in the presence of high concentrations of Brij-35 (above its CMC. Following detergent removal, the integral membrane protein was found to have been fully reconstituted into a native-like membrane environment, as confirmed by ultracentrifugation and subsequent SDS-PAGE experiments.

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

    International Nuclear Information System (INIS)

    Koutsogiannaki, Sophia; Evangelinos, Nikolaos; Koliakos, George; Kaloyianni, Martha

    2006-01-01

    The signaling mechanism induced by cadmium (Cd) and zinc (Zn) in gill cells of Mytilus galloprovincialis was investigated. Both metals cause an increase in ·O 2 - 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 ·O 2 - production was mediated via the interaction of metal ions with α 1 - 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 O 2 - 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, O 2 - production and interaction with adrenergic receptors were observed

  11. Xylose uptake by the ruminal bacterium Selenomonas ruminantium.

    Science.gov (United States)

    Williams, D K; Martin, S A

    1990-01-01

    Selenomonas ruminantium HD4 does not use the phosphoenolpyruvate phosphotransferase system to transport xylose (S. A. Martin and J. B. Russell, J. Gen. Microbiol. 134:819-827, 1988). Xylose uptake by whole cells of S. ruminantium HD4 was inducible. Uptake was unaffected by monensin or lasalocid, while oxygen, o-phenanthroline, and HgCl2 were potent inhibitors. Menadione, antimycin A, and KCN had little effect on uptake, and acriflavine inhibited uptake by 23%. Sodium fluoride decreased xylose uptake by 10%, while N,N'-dicyclohexylcarbodiimide decreased uptake by 31%. Sodium arsenate was a strong inhibitor (83%), and these results suggest the involvement of a high-energy phosphate compound and possibly a binding protein in xylose uptake. The protonophores carbonyl cyanide m-chlorophenylhydrazone, 2,4-dinitrophenol, and SF6847 inhibited xylose uptake by 88, 82, and 43%, respectively. The cations Na+ and K+ did not stimulate xylose uptake. The kinetics of xylose uptake were nonlinear, and it appeared that more than one uptake mechanism may be involved or that two proteins (i.e., a binding protein and permease protein) with different affinities for xylose were present. Excess (10 mM) glucose, sucrose, or maltose decreased xylose uptake less than 40%. Uptake was unaffected at extracellular pH values between 6.0 and 8.0, while pH values of 5.0 and 4.0 decreased uptake 28 and 24%, respectively. The phenolic monomers p-coumaric acid and vanillin inhibited growth on xylose and xylose uptake more than ferulic acid did. The predominant end products resulting from the fermentation of xylose were lactate (7.5 mM), acetate (4.4 mM), and propionate (5.1 nM), and the Yxylose was 24.1 g/mol. PMID:2383009

  12. Molecular and functional characterization of two pyruvate decarboxylase genes, PDC1 and PDC5, in the thermotolerant yeast Kluyveromyces marxianus.

    Science.gov (United States)

    Choo, Jin Ho; Han, Changpyo; Lee, Dong Wook; Sim, Gyu Hun; Moon, Hye Yun; Kim, Jae-Young; Song, Ji-Yoon; Kang, Hyun Ah

    2018-04-01

    Pyruvate decarboxylase (Pdc) is a cytosolic enzyme located at the branch point between fermentative and respiratory sugar catabolism. Here, we identified and functionally characterized KmPDC1 and KmPDC5 encoding two homologs of Pdc in the thermotolerant yeast Kluyveromyces marxianus KCTC 17555. Despite the conservation of important Pdc domains, a few amino acid sequences essential for enzymatic activity are not conserved in KmPdc5p. Deletion of KmPDC1 alone eliminated most of Pdc activity, but the growth of the Kmpdc1Δ strain on glucose was comparable to that of the wild type (WT) strain under aerobic conditions. In contrast to the WT, Kmpdc1Δ could not grow on glucose under oxygen-limited conditions. The KmPDC5 deletion did not generate any apparent change in Pdc activity or growth patterns under several tested conditions. Whereas the expression of KmPDC1 was enhanced by glucose, the basic expression levels of KmPDC5 were very low, without a detectable difference between glucose and nonfermentable carbon sources. Moreover, KmPDC5 overexpression was unable to complement the growth defect of Kmpdc1Δ in the presence of antimycin A, and the purified recombinant KmPdc5p was inactive in Pdc activity assay, supporting the notion that KmPdc5p may lack Pdc enzymatic activity. Notably, compared to the WT, Kmpdc1Δ single and Kmpdc1Δpdc5Δ double mutants produced significantly less glycerol, acetate, and ethanol while accumulating pyruvate. Altogether, our data indicate that a single deletion of KmPDC1 is sufficient in Crabtree-negative K. marxianus strains to generate a starting host strain for engineering of production of high-value biomaterials derived from pyruvate without byproduct formation.

  13. The metabolism of malate by cultured rat brain astrocytes

    Energy Technology Data Exchange (ETDEWEB)

    McKenna, M.C.; Tildon, J.T.; Couto, R.; Stevenson, J.H.; Caprio, F.J. (Department of Pediatrics, University of Maryland School of Medicine, Baltimore (USA))

    1990-12-01

    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.

  14. Modulation of intracellular calcium waves and triggered activities by mitochondrial ca flux in mouse cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Zhenghang Zhao

    Full Text Available Recent studies have suggested that mitochondria may play important roles in the Ca(2+ homeostasis of cardiac myocytes. However, it is still unclear if mitochondrial Ca(2+ flux can regulate the generation of Ca(2+ waves (CaWs and triggered activities in cardiac myocytes. In the present study, intracellular/cytosolic Ca(2+ (Cai (2+ was imaged in Fluo-4-AM loaded mouse ventricular myocytes. Spontaneous sarcoplasmic reticulum (SR Ca(2+ release and CaWs were induced in the presence of high (4 mM external Ca(2+ (Cao (2+. The protonophore carbonyl cyanide p-(trifluoromethoxyphenylhydrazone (FCCP reversibly raised basal Cai (2+ levels even after depletion of SR Ca(2+ in the absence of Cao (2+ , suggesting Ca(2+ release from mitochondria. FCCP at 0.01 - 0.1 µM partially depolarized the mitochondrial membrane potential (Δψ m and increased the frequency and amplitude of CaWs in a dose-dependent manner. Simultaneous recording of cell membrane potentials showed the augmentation of delayed afterdepolarization amplitudes and frequencies, and induction of triggered action potentials. The effect of FCCP on CaWs was mimicked by antimycin A (an electron transport chain inhibitor disrupting Δψ m or Ru360 (a mitochondrial Ca(2+ uniporter inhibitor, but not by oligomycin (an ATP synthase inhibitor or iodoacetic acid (a glycolytic inhibitor, excluding the contribution of intracellular ATP levels. The effects of FCCP on CaWs were counteracted by the mitochondrial permeability transition pore blocker cyclosporine A, or the mitochondrial Ca(2+ uniporter activator kaempferol. Our results suggest that mitochondrial Ca(2+ release and uptake exquisitely control the local Ca(2+ level in the micro-domain near SR ryanodine receptors and play an important role in regulation of intracellular CaWs and arrhythmogenesis.

  15. Opening of the mitochondrial permeability transition pore links mitochondrial dysfunction to insulin resistance in skeletal muscle.

    Science.gov (United States)

    Taddeo, E P; Laker, R C; Breen, D S; Akhtar, Y N; Kenwood, B M; Liao, J A; Zhang, M; Fazakerley, D J; Tomsig, J L; Harris, T E; Keller, S R; Chow, J D; Lynch, K R; Chokki, M; Molkentin, J D; Turner, N; James, D E; Yan, Z; Hoehn, K L

    2014-04-01

    Insulin resistance is associated with mitochondrial dysfunction, but the mechanism by which mitochondria inhibit insulin-stimulated glucose uptake into the cytoplasm is unclear. The mitochondrial permeability transition pore (mPTP) is a protein complex that facilitates the exchange of molecules between the mitochondrial matrix and cytoplasm, and opening of the mPTP occurs in response to physiological stressors that are associated with insulin resistance. In this study, we investigated whether mPTP opening provides a link between mitochondrial dysfunction and insulin resistance by inhibiting the mPTP gatekeeper protein cyclophilin D (CypD) in vivo and in vitro. Mice lacking CypD were protected from high fat diet-induced glucose intolerance due to increased glucose uptake in skeletal muscle. The mitochondria in CypD knockout muscle were resistant to diet-induced swelling and had improved calcium retention capacity compared to controls; however, no changes were observed in muscle oxidative damage, insulin signaling, lipotoxic lipid accumulation or mitochondrial bioenergetics. In vitro, we tested 4 models of insulin resistance that are linked to mitochondrial dysfunction in cultured skeletal muscle cells including antimycin A, C2-ceramide, ferutinin, and palmitate. In all models, we observed that pharmacological inhibition of mPTP opening with the CypD inhibitor cyclosporin A was sufficient to prevent insulin resistance at the level of insulin-stimulated GLUT4 translocation to the plasma membrane. The protective effects of mPTP inhibition on insulin sensitivity were associated with improved mitochondrial calcium retention capacity but did not involve changes in insulin signaling both in vitro and in vivo. In sum, these data place the mPTP at a critical intersection between alterations in mitochondrial function and insulin resistance in skeletal muscle.

  16. Obesity-exposed oocytes accumulate and transmit damaged mitochondria due to an inability to activate mitophagy.

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    Boudoures, Anna L; Saben, Jessica; Drury, Andrea; Scheaffer, Suzanne; Modi, Zeel; Zhang, Wendy; Moley, Kelle H

    2017-06-01

    Mitochondria are the most prominent organelle in the oocyte. Somatic cells maintain a healthy population of mitochondria by degrading damaged mitochondria via mitophagy, a specialized autophagy pathway. However, evidence from previous work investigating the more general macroautophagy pathway in oocytes suggests that mitophagy may not be active in the oocyte. This would leave the vast numbers of mitochondria - poised to be inherited by the offspring - vulnerable to damage. Here we test the hypothesis that inactive mitophagy in the oocyte underlies maternal transmission of dysfunctional mitochondria. To determine whether oocytes can complete mitophagy, we used either CCCP or AntimycinA to depolarize mitochondria and trigger mitophagy. After depolarization, we did not detect co-localization of mitochondria with autophagosomes and mitochondrial DNA copy number remained unchanged, indicating the non-functional mitochondrial population was not removed. To investigate the impact of an absence of mitophagy in oocytes with damaged mitochondria on offspring mitochondrial function, we utilized in vitro fertilization of high fat high sugar (HF/HS)-exposed oocytes, which have lower mitochondrial membrane potential and damaged mitochondria. Here, we demonstrate that blastocysts generated from HF/HS oocytes have decreased mitochondrial membrane potential, lower metabolites involved in ATP generation, and accumulation of PINK1, a mitophagy marker protein. This mitochondrial phenotype in the blastocyst mirrors the phenotype we show in HF/HS exposed oocytes. Taken together, these data suggest that the mechanisms governing oocyte mitophagy are fundamentally distinct from those governing somatic cell mitophagy and that the absence of mitophagy in the setting of HF/HS exposure contributes to the oocyte-to-blastocyst transmission of dysfunctional mitochondria. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Effects of Ca2+, Mg2+, and depolarizing agents, on the 32Pi-labeling and degradation of phosphatidylinositols in rat brain synaptosomes.

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    Marinetti, G V; Morris, T W; Leaky, P

    1993-03-01

    In isolated synaptosomes from rat brain, 100 microM antimycin A and 10 microM oxamic acid inhibit the 32Pi-labeling of phosphatidylinositol-4,5-bisphosphate (PIP2) and phosphatidylinositol-4-phosphate (PIP) by 90% and 95-99% respectively. 10 mM sodium fluoride inhibits the labeling by 50-60% and 10 mM A23187 inhibits the labeling by 63-70%. Phospholipase A2 inhibits the labeling of PIP2 and PIP by 93-94% and stimulates their degradation by 84-92%. Depolarization of synaptosomes with 75 mM K+ or 100 microM veratrine decreases the labeling of PIP2 and PIP by 66-74%. The decreased labeling results in large part from the Ca(2+)-dependent degradation of 32P-labeled PIP2 and PIP as shown by pulse-chase experiments in which PIP2 and PIP were prelabeled with 32Pi. Depolarization of synaptosomes results in the stimulation of 45Ca2+ uptake with the concomitant hydrolysis of PIP and PIP2. Addition of 1 mM Ca2+ accounts for 25% of the enhanced degradation whereas depolarization with 75 mM K+ accounts for 75% of the enhanced degradation of PIP2 and PIP. Depolarization with 100 mM veratrine results in a 223% increase in inositol trisphosphate as evidenced by stimulation of 45Ca2+ uptake. EGTA (10 mM) and Mg2+ (5-10 mM) inhibit the degradation of PIP and PIP2 and counteract the action of 1 mM Ca2+. Our data demonstrate that 45Ca2+, Mg2+, and membrane depolarization play an important role in the turnover of membrane phosphatidylinositols.

  18. Sustained Submicromolar H2O2 Levels Induce Hepcidin via Signal Transducer and Activator of Transcription 3 (STAT3)*

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    Millonig, Gunda; Ganzleben, Ingo; Peccerella, Teresa; Casanovas, Guillem; Brodziak-Jarosz, Lidia; Breitkopf-Heinlein, Katja; Dick, Tobias P.; Seitz, Helmut-Karl; Muckenthaler, Martina U.; Mueller, Sebastian

    2012-01-01

    The peptide hormone hepcidin regulates mammalian iron homeostasis by blocking ferroportin-mediated iron export from macrophages and the duodenum. During inflammation, hepcidin is strongly induced by interleukin 6, eventually leading to the anemia of chronic disease. Here we show that hepatoma cells and primary hepatocytes strongly up-regulate hepcidin when exposed to low concentrations of H2O2 (0.3–6 μm), concentrations that are comparable with levels of H2O2 released by inflammatory cells. In contrast, bolus treatment of H2O2 has no effect at low concentrations and even suppresses hepcidin at concentrations of >50 μm. H2O2 treatment synergistically stimulates hepcidin promoter activity in combination with recombinant interleukin-6 or bone morphogenetic protein-6 and in a manner that requires a functional STAT3-responsive element. The H2O2-mediated hepcidin induction requires STAT3 phosphorylation and is effectively blocked by siRNA-mediated STAT3 silencing, overexpression of SOCS3 (suppressor of cytokine signaling 3), and antioxidants such as N-acetylcysteine. Glycoprotein 130 (gp130) is required for H2O2 responsiveness, and Janus kinase 1 (JAK1) is required for adequate basal signaling, whereas Janus kinase 2 (JAK2) is dispensable upstream of STAT3. Importantly, hepcidin levels are also increased by intracellular H2O2 released from the respiratory chain in the presence of rotenone or antimycin A. Our results suggest a novel mechanism of hepcidin regulation by nanomolar levels of sustained H2O2. Thus, similar to cytokines, H2O2 provides an important regulatory link between inflammation and iron metabolism. PMID:22932892

  19. NQO1-dependent redox cycling of idebenone: effects on cellular redox potential and energy levels.

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    Roman H Haefeli

    Full Text Available Short-chain quinones are described as potent antioxidants and in the case of idebenone have already been under clinical investigation for the treatment of neuromuscular disorders. Due to their analogy to coenzyme Q10 (CoQ10, a long-chain quinone, they are widely regarded as a substitute for CoQ10. However, apart from their antioxidant function, this provides no clear rationale for their use in disorders with normal CoQ10 levels. Using recombinant NAD(PH:quinone oxidoreductase (NQO enzymes, we observed that contrary to CoQ10 short-chain quinones such as idebenone are good substrates for both NQO1 and NQO2. Furthermore, the reduction of short-chain quinones by NQOs enabled an antimycin A-sensitive transfer of electrons from cytosolic NAD(PH to the mitochondrial respiratory chain in both human hepatoma cells (HepG2 and freshly isolated mouse hepatocytes. Consistent with the substrate selectivity of NQOs, both idebenone and CoQ1, but not CoQ10, partially restored cellular ATP levels under conditions of impaired complex I function. The observed cytosolic-mitochondrial shuttling of idebenone and CoQ1 was also associated with reduced lactate production by cybrid cells from mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS patients. Thus, the observed activities separate the effectiveness of short-chain quinones from the related long-chain CoQ10 and provide the rationale for the use of short-chain quinones such as idebenone for the treatment of mitochondrial disorders.

  20. 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

    Science.gov (United States)

    Zoll, Joffrey; Bouitbir, Jamal; Sirvent, Pascal; Klein, Alexis; Charton, Antoine; Jimenez, Liliana; Péronnet, François R; Geny, Bernard; Richard, Ruddy

    2015-01-01

    Background 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 significantly lower with both electron donors in water enriched in O2 by electrolysis. This was not associated with any increase in the sensitivity of mitochondria to ADP; no significant difference was observed for the Km ADP between the two waters. Conclusion In this experiment, a higher affinity of the mitochondria for O2 was observed in water enriched in O2 by electrolysis than by injection. This observation is consistent with the hypothesis that O2 diffusion can be facilitated in water enriched in O2 by the electrolytic process. PMID:26203225

  1. 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.

  2. Endoplasmic Reticulum Stress-Induced Autophagy Provides Cytoprotection from Chemical Hypoxia and Oxidant Injury and Ameliorates Renal Ischemia-Reperfusion Injury.

    Directory of Open Access Journals (Sweden)

    Bhavya B Chandrika

    Full Text Available We examined whether endoplasmic reticulum (ER stress-induced autophagy provides cytoprotection from renal tubular epithelial cell injury due to oxidants and chemical hypoxia in vitro, as well as from ischemia-reperfusion (IR injury in vivo. We demonstrate that the ER stress inducer tunicamycin triggers an unfolded protein response, upregulates ER chaperone Grp78, and activates the autophagy pathway in renal tubular epithelial cells in culture. Inhibition of ER stress-induced autophagy accelerated caspase-3 activation and cell death suggesting a pro-survival role of ER stress-induced autophagy. Compared to wild-type cells, autophagy-deficient MEFs subjected to ER stress had enhanced caspase-3 activation and cell death, a finding that further supports the cytoprotective role of ER stress-induced autophagy. Induction of autophagy by ER stress markedly afforded cytoprotection from oxidants H2O2 and tert-Butyl hydroperoxide and from chemical hypoxia induced by antimycin A. In contrast, inhibition of ER stress-induced autophagy or autophagy-deficient cells markedly enhanced cell death in response to oxidant injury and chemical hypoxia. In mouse kidney, similarly to renal epithelial cells in culture, tunicamycin triggered ER stress, markedly upregulated Grp78, and activated autophagy without impairing the autophagic flux. In addition, ER stress-induced autophagy markedly ameliorated renal IR injury as evident from significant improvement in renal function and histology. Inhibition of autophagy by chloroquine markedly increased renal IR injury. These studies highlight beneficial impact of ER stress-induced autophagy in renal ischemia-reperfusion injury both in vitro and in vivo.

  3. Mitochondrial Superoxide Generation Enhances P2X7R-mediated Loss of Cell Surface CD62L on Naïve Human CD4+ T Lymphocytes1

    Science.gov (United States)

    Foster, John G.; Carter, Edward; Kilty, Iain; MacKenzie, Amanda B.; Ward, Stephen G.

    2013-01-01

    Migration of naïve CD4+ T lymphocytes into lymphoid tissue is essential for their activation and subsequent roles in adaptive immunity. The adhesion molecule CD62L, critical for this process, is highly expressed on naïve CD4+ T lymphocytes and is down-regulated upon T lymphocyte activation. We demonstrate protein expression of P2X7R on naïve CD4+ T lymphocytes and show functional channel activity in whole cell patch clamp recordings. CD62L down-regulation occurs rapidly in response to extracellular ATP, a process which is blocked by selective antagonists of P2X7R. This loss of surface CD62L expression was not associated with externalization of phosphatidyl serine. While investigating the mechanisms for this process we revealed that pharmacological modulation of mitochondrial complex I or III, but not inhibition of NADPH oxidase, enhanced P2X7R dependent CD62L down-regulation by increasing ATP potency. Enhanced superoxide generation in the mitochondria of Rotenone and Antimycin A treated cells was observed and may contribute to the enhanced sensitivity of P2X7R to ATP. P2X7R dependent exposure of phosphatidylserine was also revealed by pre-incubation with mitochondrial un-couplers prior to ATP treatment. This may present a novel mechanism whereby P2X7R dependent PS exposure occurs only when cells have enhanced mitochondrial ROS generation. The clearance of apoptotic cells may therefore be enhanced by this mechanism which requires functional P2X7R expression. PMID:23319734

  4. Mitochondrial superoxide generation enhances P2X7R-mediated loss of cell surface CD62L on naive human CD4+ T lymphocytes.

    Science.gov (United States)

    Foster, John G; Carter, Edward; Kilty, Iain; MacKenzie, Amanda B; Ward, Stephen G

    2013-02-15

    Migration of naive CD4(+) T lymphocytes into lymphoid tissue is essential for their activation and subsequent roles in adaptive immunity. The adhesion molecule L-selectin (CD62L), critical for this process, is highly expressed on naive CD4(+) T lymphocytes and is downregulated upon T lymphocyte activation. We demonstrate protein expression of P2X7R on naive CD4(+) T lymphocytes and show functional channel activity in whole-cell patch clamp recordings. CD62L downregulation occurs rapidly in response to extracellular ATP, a process that is blocked by selective antagonists of P2X7R. This loss of surface CD62L expression was not associated with externalization of phosphatidylserine. While investigating the mechanisms for this process, we revealed that pharmacological modulation of mitochondrial complex I or III, but not inhibition of NADPH oxidase, enhanced P2X7R-dependent CD62L downregulation by increasing ATP potency. Enhanced superoxide generation in the mitochondria of rotenone- and antimycin A-treated cells was observed and may contribute to the enhanced sensitivity of P2X7R to ATP. P2X7R-dependent exposure of phosphatidylserine was also revealed by preincubation with mitochondrial uncouplers prior to ATP treatment. This may present a novel mechanism whereby P2X7R-dependent phosphatidylserine exposure occurs only when cells have enhanced mitochondrial reactive oxygen species generation. The clearance of apoptotic cells may therefore be enhanced by this mechanism which requires functional P2X7R expression.

  5. Mitochondrial Complexes I and II Are More Susceptible to Autophagy Deficiency in Mouse β-Cells

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    Min Joo Kim

    2015-03-01

    Full Text Available BackgroundDamaged mitochondria are removed by autophagy. Therefore, impairment of autophagy induces the accumulation of damaged mitochondria and mitochondrial dysfunction in most mammalian cells. Here, we investigated mitochondrial function and the expression of mitochondrial complexes in autophagy-related 7 (Atg7-deficient β-cells.MethodsTo evaluate the effect of autophagy deficiency on mitochondrial function in pancreatic β-cells, we isolated islets from Atg7F/F:RIP-Cre+ mice and wild-type littermates. Oxygen consumption rate and intracellular adenosine 5'-triphosphate (ATP content were measured. The expression of mitochondrial complex genes in Atg7-deficient islets and in β-TC6 cells transfected with siAtg7 was measured by quantitative real-time polymerase chain reaction.ResultsBaseline oxygen consumption rate of Atg7-deficient islets was significantly lower than that of control islets (P<0.05. Intracellular ATP content of Atg7-deficient islets during glucose stimulation was also significantly lower than that of control islets (P<0.05. By Oxygraph-2k analysis, mitochondrial respiration in Atg7-deficient islets was significantly decreased overall, although state 3 respiration and responses to antimycin A were unaffected. The mRNA levels of mitochondrial complexes I, II, III, and V in Atg7-deficient islets were significantly lower than in control islets (P<0.05. Down-regulation of Atg7 in β-TC6 cells also reduced the expression of complexes I and II, with marginal significance (P<0.1.ConclusionImpairment of autophagy in pancreatic β-cells suppressed the expression of some mitochondrial respiratory complexes, and may contribute to mitochondrial dysfunction. Among the complexes, I and II seem to be most vulnerable to autophagy deficiency.

  6. A

    Directory of Open Access Journals (Sweden)

    Morteza Bahram

    2016-09-01

    Full Text Available We report on a new method for the preconcentration and microextraction of analytes from aqueous samples using a pH-sensitive hydrogel. It is referred to as semisolid–liquid dispersive microextraction (SSLDM and has the advantages of both dispersive liquid–liquid microextraction (DLLME and solid-phase extraction (SPE. The surface area of the droplets is large, so the equilibrium state is quickly reached. The high density of the gel facilitates phase separation, and disadvantages of existing methods are overcome in that there is no need for extraction and dispersive solvents (as in conventional DLLME and no need for desorption (as in SPE. The SSLDM method integrates sampling, extraction and concentration into one single and solvent-free step. The method was exemplarily applied to the preconcentration of malachite green (MG and crystal violet (CV which then were quantified by spectrophotometry. Specifically, poly (styrene-alt-maleic acid, a pH-sensitive hydrogel, was used to extract MG and CV from water samples. The linear analytical range is from 0.01 to 1 μmol L−1 for MG, and from 0.05 to 1 μmol L−1 for CV. The correlation coefficient for MG and CV is 0.999 and 0.993, respectively. The limit of detection for MG and CV is 0.011 and 0.014 μmol L−1, respectively.

  7. Importance of the alternative oxidase (AOX) pathway in regulating cellular redox and ROS homeostasis to optimize photosynthesis during restriction of the cytochrome oxidase pathway in Arabidopsis thaliana.

    Science.gov (United States)

    Vishwakarma, Abhaypratap; Tetali, Sarada Devi; Selinski, Jennifer; Scheibe, Renate; Padmasree, Kollipara

    2015-09-01

    The importance of the alternative oxidase (AOX) pathway, particularly AOX1A, in optimizing photosynthesis during de-etiolation, under elevated CO2, low temperature, high light or combined light and drought stress is well documented. In the present study, the role of AOX1A in optimizing photosynthesis was investigated when electron transport through the cytochrome c oxidase (COX) pathway was restricted at complex III. Leaf discs of wild-type (WT) and aox1a knock-out mutants of Arabidopsis thaliana were treated with antimycin A (AA) under growth-light conditions. To identify the impact of AOX1A deficiency in optimizing photosynthesis, respiratory O2 uptake and photosynthesis-related parameters were measured along with changes in redox couples, reactive oxygen species (ROS), lipid peroxidation and expression levels of genes related to respiration, the malate valve and the antioxidative system. In the absence of AA, aox1a knock-out mutants did not show any difference in physiological, biochemical or molecular parameters compared with WT. However, after AA treatment, aox1a plants showed a significant reduction in both respiratory O2 uptake and NaHCO3-dependent O2 evolution. Chlorophyll fluorescence and P700 studies revealed that in contrast to WT, aox1a knock-out plants were incapable of maintaining electron flow in the chloroplastic electron transport chain, and thereby inefficient heat dissipation (low non-photochemical quenching) was observed. Furthermore, aox1a mutants exhibited significant disturbances in cellular redox couples of NAD(P)H and ascorbate (Asc) and consequently accumulation of ROS and malondialdehyde (MDA) content. By contrast, WT plants showed a significant increase in transcript levels of CSD1, CAT1, sAPX, COX15 and AOX1A in contrast to aox1a mutants. These results suggest that AOX1A plays a significant role in sustaining the chloroplastic redox state and energization to optimize photosynthesis by regulating cellular redox homeostasis and ROS

  8. [Organ transplantation. One of the biochemical reasons for the race against the clock].

    Science.gov (United States)

    Zénatti, M; Emeric-Blanchouin, N; Bitker, M O; Barrou, B; Lugagne, P M; Thallier, M; Aupetit-Faisant, B

    1991-11-27

    The authors have studied the subcellular functioning of human adrenal glands removed from subjects in a stage IV coma. The present study has a two-fold interest: on the one hand, it offers biochemical information on a key element in the intermediate metabolism (namely, the mitochondrial energetic metabolism, occurring in a fragile tissue which, under a state of shock, is primarily affected; the results obtained on such type of tissue may therefore be inferred to other organs); on the other hand, it allows a wider approach of the adrenal biochemical mechanisms during a stage IV coma. The mitochondrial fraction was obtained by differential centrifugation carried out immediately after organ removal. The steroid synthesis, studied using radioactive precursors, turned out to be similar to that found in other mammals. Respiratory characteristics, determined by polarography with a Clark oxygen electrode, at 37 degrees C, were satisfactory: respiratory intensity was 77.25 +/- 12.16 nanomoles O2/min/mg mitochondrial protein in the presence of succinate 15 mM and respiratory control was 1.93 +/- 0.15 in the presence of ADP 37 microM. The respiratory chain functioned in a classical manner: rotenone 25 microM did not inhibit respiration in the presence of succinate 15 mM, while it did with L-malate 15 mM. In the presence of succinate 15 mM, the respiratory intensity was inhibited at 87.4 percent and 76.7 percent by KCN 0.01 microM and antimycin A 0.09 microM respectively; with DNP 85 microM, it was multiplied by 5. However, the value of the P/O ratio was low (0.24 +/- 0.04). Under the present conditions, this may highlight the difficulty to synthetize ATP whenever neither the functioning nor the regulation of the multi-enzymatic complex accounting for oxygen consumption are affected. This result clearly confirms that the shortest possible delay between organ removal and transplantation is crucial, as the renewal of cell structures requires energy. These fundamental research

  9. Visualizing changes in electron distribution in coupled chains of cytochrome bc(1) by modifying barrier for electron transfer between the FeS cluster and heme c(1).

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    Cieluch, Ewelina; Pietryga, Krzysztof; Sarewicz, Marcin; Osyczka, Artur

    2010-02-01

    Cytochrome c(1) of Rhodobacter (Rba.) species provides a series of mutants which change barriers for electron transfer through the cofactor chains of cytochrome bc(1) by modifying heme c(1) redox midpoint potential. Analysis of post-flash electron distribution in such systems can provide useful information about the contribution of individual reactions to the overall electron flow. In Rba. capsulatus, the non-functional low-potential forms of cytochrome c(1) which are devoid of the disulfide bond naturally present in this protein revert spontaneously by introducing a second-site suppression (mutation A181T) that brings the potential of heme c(1) back to the functionally high levels, yet maintains it some 100 mV lower from the native value. Here we report that the disulfide and the mutation A181T can coexist in one protein but the mutation exerts a dominant effect on the redox properties of heme c(1) and the potential remains at the same lower value as in the disulfide-free form. This establishes effective means to modify a barrier for electron transfer between the FeS cluster and heme c(1) without breaking disulfide. A comparison of the flash-induced electron transfers in native and mutated cytochrome bc(1) revealed significant differences in the post-flash equilibrium distribution of electrons only when the connection of the chains with the quinone pool was interrupted at the level of either of the catalytic sites by the use of specific inhibitors, antimycin or myxothiazol. In the non-inhibited system no such differences were observed. We explain the results using a kinetic model in which a shift in the equilibrium of one reaction influences the equilibrium of all remaining reactions in the cofactor chains. It follows a rather simple description in which the direction of electron flow through the coupled chains of cytochrome bc(1) exclusively depends on the rates of all reversible partial reactions, including the Q/QH2 exchange rate to/from the catalytic sites

  10. Metformin as a prevention and treatment for preeclampsia: effects on soluble fms-like tyrosine kinase 1 and soluble endoglin secretion and endothelial dysfunction.

    Science.gov (United States)

    Brownfoot, Fiona C; Hastie, Roxanne; Hannan, Natalie J; Cannon, Ping; Tuohey, Laura; Parry, Laura J; Senadheera, Sevvandi; Illanes, Sebastian E; Kaitu'u-Lino, Tu'uhevaha J; Tong, Stephen

    2016-03-01

    explant-conditioned media (to whole vessels). Finally, we examined the effects of metformin on angiogenesis on maternal omental vessel explants. Metformin reduced soluble fms-like tyrosine kinase 1 and soluble endoglin secretion from primary endothelial cells, villous cytotrophoblast cells, and preterm preeclamptic placental villous explants. The reduction in soluble fms-like tyrosine kinase 1 and soluble endoglin secretion was rescued by coadministration of succinate, which suggests that the effects of metformin on soluble fms-like tyrosine kinase 1 and soluble endoglin were likely to be regulated at the level of the mitochondria. In addition, the mitochondrial electron transport chain inhibitors rotenone and antimycin reduced soluble fms-like tyrosine kinase 1 secretion, which further suggests that soluble fms-like tyrosine kinase 1 secretion is regulated through the mitochondria. Mitochondrial electron transport chain activity in preterm preeclamptic placentas was increased compared with gestation-matched control subjects. Metformin improved features of endothelial dysfunction relevant to preeclampsia. It reduced endothelial cell messenger RNA expression of vascular cell adhesion molecule 1 that was induced by tumor necrosis factor-α (vascular cell adhesion molecule 1 is an inflammatory adhesion molecule up-regulated with endothelial dysfunction and is increased in preeclampsia). Placental conditioned media impaired bradykinin-induced vasodilation; this effect was reversed by metformin. Metformin also improved whole blood vessel angiogenesis impaired by fms-like tyrosine kinase 1. Metformin reduced soluble fms-like tyrosine kinase 1 and soluble endoglin secretion from primary human tissues, possibly by inhibiting the mitochondrial electron transport chain. The activity of the mitochondrial electron transport chain was increased in preterm preeclamptic placenta. Metformin reduced endothelial dysfunction, enhanced vasodilation in omental arteries, and induced

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

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    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

  12. 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

  13. Hearts deficient in both Mfn1 and Mfn2 are protected against acute myocardial infarction.

    Science.gov (United States)

    Hall, A R; Burke, N; Dongworth, R K; Kalkhoran, S B; Dyson, A; Vicencio, J M; Dorn, G W; Yellon, D M; Hausenloy, D J

    2016-05-26

    Mitochondria alter their shape by undergoing cycles of fusion and fission. Changes in mitochondrial morphology impact on the cellular response to stress, and their interactions with other organelles such as the sarcoplasmic reticulum (SR). Inhibiting mitochondrial fission can protect the heart against acute ischemia/reperfusion (I/R) injury. However, the role of the mitochondrial fusion proteins, Mfn1 and Mfn2, in the response of the adult heart to acute I/R injury is not clear, and is investigated in this study. To determine the effect of combined Mfn1/Mfn2 ablation on the susceptibility to acute myocardial I/R injury, cardiac-specific ablation of both Mfn1 and Mfn2 (DKO) was initiated in mice aged 4-6 weeks, leading to knockout of both these proteins in 8-10-week-old animals. This resulted in fragmented mitochondria (electron microscopy), decreased mitochondrial respiratory function (respirometry), and impaired myocardial contractile function (echocardiography). In DKO mice subjected to in vivo regional myocardial ischemia (30 min) followed by 24 h reperfusion, myocardial infarct size (IS, expressed as a % of the area-at-risk) was reduced by 46% compared with wild-type (WT) hearts. In addition, mitochondria from DKO animals had decreased MPTP opening susceptibility (assessed by Ca(2+)-induced mitochondrial swelling), compared with WT hearts. Mfn2 is a key mediator of mitochondrial/SR tethering, and accordingly, the loss of Mfn2 in DKO hearts reduced the number of interactions measured between these organelles (quantified by proximal ligation assay), attenuated mitochondrial calcium overload (Rhod2 confocal microscopy), and decreased reactive oxygen species production (DCF confocal microscopy) in response to acute I/R injury. No differences in isolated mitochondrial ROS emissions (Amplex Red) were detected in response to Ca(2+) and Antimycin A, further implicating disruption of mitochondria/SR tethering as the protective mechanism. In summary, despite apparent

  14. The electron transport system of the anaerobic Propionibacterium shermanii: cytochrome and inhibitor studies.

    Science.gov (United States)

    Schwartz, A C; Sporkenbach, J

    1975-03-10

    1. Electron transport particles obtained from cell-free extracts of Propionibacterium shermanii by centrifugation at 105000 times g for 3 hrs oxidized NADH, D,L-lactate, L-glycerol-3-phosphate and succinate with oxygen and, except for succinate, with fumarate, too. 2. Spectral investigation of the electron transport particles revealed the presence of cytochromes b, d and o, and traces of cytochrome alpha1 and a c-type cytochrome. Cytochrome b was reduced by succinate to about 50%, and by NADH, lactate or glycerol-3-phosphate to 80--90%. 3. The inhibitory effects of amytal and rotenone on NADH oxidation, but not on the oxidation of the other substrates, indicated the presence of the NADH dehydrogenase complex, or "site I region", in the electron transport system of P. shermanii. 4. NQNO inhibited substrate oxidations by oxygen and fumarate, as well as equilibration of the flavoproteins of the substrate dehydrogenases by way of menaquinone. The inhibition occurred at low concentrations of the inhibitor and reached 80--100%, depending on the substrate tested. The site of inhibition of the respiratory activity was located between menaquinone and cytochrome b. In addition, inhibition of flavoprotein equilibration suggested that NQNO acted upon the electron transfer directed from menaquinol towards the acceptor to be reduced, either cytochrome b or the flavoproteins, which would include fumarate reductase. 5. In NQNO-inhibited particles, cytochrome b was not oxidized by oxygen-free fumarate, but readily oxidized by oxygen. It was concluded from this and the above evidence that the branching-point of the electron transport chain towards fumarate reductase was located at the menaquinone in P. shermanii. It was further concluded that all cytochromes were situated in the oxygen-linked branch of the chain, which formed a dead end of the system under anaerobic conditions. 6. Antimycin A inhibited only oxygen-linked reactions of the particles to about 50% at high concentrations

  15. Effect of artificial and natural phospholipid membranes on rate of sperm whale oxymyoglobin autooxidation.

    Science.gov (United States)

    Postnikova, G B; Shekhovtsova, E A

    2013-03-01

    We were the first to show that MbO2 deoxygenation in the cell occurs only upon interaction of myoglobin with mitochondrial membrane, which must be accompanied by changes in the heme cavity conformation of the protein and its affinity for the ligand. Under aerobic conditions, some changes in the equilibrium O2 dissociation constant (Kdis) can be detected by changes of the rate of MbO2 autooxidation, i.e. spontaneous turning it into metMb (kox), as far as a direct correlation between Kdis and kox is experimentally shown. In this work, we studied the effect on MbO2 autooxidation rate of phospholipid liposomes from neutral soybean phosphatidylcholine (lecithin) and from negatively charged 1-palmitoyl-2-oleylphosphatidylglycerol (POPG) at various phospholipid/MbO2 ratios from 25 : 1 to 100 : 1, and also the effect of rat liver mitochondria at concentration of 1 and 2 mg/ml mitochondrial protein (at 22 and 37°C). In all cases, kox was found to increase due to interaction of the protein with phospholipid membranes. The effect of negatively charged liposomes from POPG on kox is significantly greater than that of neutral lecithin liposomes. At the POPG/MbO2 molar ratio of 25 : 1, MbO2 autooxidation rate is almost 25-fold increased compared to the control, whereas in the presence of 50-fold molar excess of lecithin, kox is only ~10 times higher (10 mM buffer, pH 7.2, 22°C). With the same phospholipid/MbO2 ratio of 100 : 1, kox is 7 times higher for the POPG than for lecithin liposomes. In the presence of mitochondria inhibited by antimycin A, kox grows proportionally to their concentration (about 10-fold per 1 mg/ml of mitochondrial protein), and practically does not change after adding superoxide dismutase in the reaction mixture. The kox value decreases markedly at high ionic strength, thus suggesting an important role of coulombic electrostatics in the myoglobin-mitochondrial interaction. The increase in the autooxidation rate of MbO2 (and hence its Kdis) due to the

  16. 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.

  17. 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)

    Ramos-Filho, Dionizio; Chicaybam, Gustavo; 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.

  18. Physiological Levels of Nitric Oxide Diminish Mitochondrial Superoxide. Potential Role of Mitochondrial Dinitrosyl Iron Complexes and Nitrosothiols

    Directory of Open Access Journals (Sweden)

    Sergey I. Dikalov

    2017-11-01

    Full Text Available Mitochondria are the major source of superoxide radicals and superoxide overproduction contributes to cardiovascular diseases and metabolic disorders. Endothelial dysfunction and diminished nitric oxide levels are early steps in the development of these pathological conditions. It is known that physiological production of nitric oxide reduces oxidative stress and inflammation, however, the precise mechanism of “antioxidant” effect of nitric oxide is not clear. In this work we tested the hypothesis that physiological levels of nitric oxide diminish mitochondrial superoxide production without inhibition of mitochondrial respiration. In order to test this hypothesis we analyzed effect of low physiological fluxes of nitric oxide (20 nM/min on superoxide and hydrogen peroxide production by ESR spin probes and Amplex Red in isolated rat brain mitochondria. Indeed, low levels of nitric oxide substantially attenuated both basal and antimycin A-stimulated production of reactive oxygen species in the presence of succinate or glutamate/malate as mitochondrial substrates. Furthermore, slow releasing NO donor DPTA-NONOate (100 μM did not change oxygen consumption in State 4 and State 3. However, the NO-donor strongly inhibited oxygen consumption in the presence of uncoupling agent CCCP, which is likely associated with inhibition of the over-reduced complex IV in uncoupled mitochondria. We have examined accumulation of dinitrosyl iron complexes and nitrosothiols in mitochondria treated with fast-releasing NO donor MAHMA NONOate (10 μM for 30 min until complete release of NO. Following treatment with NO donor, mitochondria were frozen for direct detection of dinitrosyl iron complexes using Electron Spin Resonance (ESR while accumulation of nitrosothiols was measured by ferrous-N-Methyl-D-glucamine dithiocarbamate complex, Fe(MGD2, in lysed mitochondria. Treatment of mitochondria with NO-donor gave rise to ESR signal of dinitrosyl iron complexes while ESR

  19. ~.ss _:s A~ ) A ~ =~A

    African Journals Online (AJOL)

    An Cosantoir, vol 28, no 4 April 1968 m.H. Liddell. Hart: Strategy of a war), p 117. 24. F.W. von Mellenthin: Panzer baules: a srudy of the em. ployment of armour in the Second World War, (New York. 1956) p 273. Scientia Militaria, South African Journal of Military Studies, Vol 8, Nr 4, 1978. http://scientiamilitaria.journals.ac.

  20. 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

    Directory of Open Access Journals (Sweden)

    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

  1. A A Munot

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science. A A Munot. Articles written in Journal of Earth System Science. Volume 116 Issue 1 February 2007 pp 73-79. Long range prediction of Indian summer monsoon rainfall · A A Munot K Krishna Kumar · More Details Abstract Fulltext PDF. The search for new parameters for ...

  2. Deshpande, Dr A A

    Indian Academy of Sciences (India)

    Period: 1989–1993. Deshpande, Dr A A . Date of birth: 23 January 1958. Specialization: Observational Radio Astronomy Address during Associateship: Raman Research Institute, C.V. Raman Avenue, Sadashivanagar P.O, Bangalore 560 080.

  3. a a m prince

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences. A A M PRINCE. Articles written in Journal of Chemical Sciences. Volume 128 Issue 5 May 2016 pp 787-802 Regular Articles. Flexible synthesis of isomeric pyranoindolones and evaluation of cytotoxicity towards HeLa cells · J C JEYAVEERAN CHANDRASEKAR PRAVEEN Y ...

  4. S A H A R A J

    African Journals Online (AJOL)

    The book is essentially a doctoral thesis and, as such, offers a very detailed study of the impact of AIDS on banana-farming households in two Ugandan districts. Being based on a thesis means that it should not be regarded as a general text on AIDS and livelihoods, but it does offer many insights into the reality of living with ...

  5. Venice: a meeting, a plague, a death

    Directory of Open Access Journals (Sweden)

    Óscar Botasso

    2008-10-01

    Full Text Available Death in Venice is based on the novella of the same name by Thomas Mann, except that in the cinema version the main character, Gustav von Aschenbach, is a musician instead of a writer. Owing to poetic license not always within the layman’s grasp, Luchino Visconti also wished to identify the artist with Gustav Mahler. Beyond such dissimilarities, however, the film is a feasible recreation of the story and a faithful reconstruction of those times: a Venice divorced from its former splendor and invaded by a plague and yet at the same time still able to evoke the captivating, nostalgic legacy of its magnificent past. An ideal scenario indeed for the musical ideas of Mahler, and perfectly reflected in the Midnight Song and the adagietto of his third and fifth symphonies.

  6. A* Sampling

    OpenAIRE

    Maddison, Chris J.; Tarlow, Daniel; Minka, Tom

    2014-01-01

    The problem of drawing samples from a discrete distribution can be converted into a discrete optimization problem. In this work, we show how sampling from a continuous distribution can be converted into an optimization problem over continuous space. Central to the method is a stochastic process recently described in mathematical statistics that we call the Gumbel process. We present a new construction of the Gumbel process and A* sampling, a practical generic sampling algorithm that searches ...

  7. 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 ...

  8. A Survey of Parallel A*

    OpenAIRE

    Fukunaga, Alex; Botea, Adi; Jinnai, Yuu; Kishimoto, Akihiro

    2017-01-01

    A* is a best-first search algorithm for finding optimal-cost paths in graphs. A* benefits significantly from parallelism because in many applications, A* is limited by memory usage, so distributed memory implementations of A* that use all of the aggregate memory on the cluster enable problems that can not be solved by serial, single-machine implementations to be solved. We survey approaches to parallel A*, focusing on decentralized approaches to A* which partition the state space among proces...

  9. Fadeyi, A

    African Journals Online (AJOL)

    Fadeyi, A. Vol 17, No 1 (2010) - Articles Prevalence of intestinal parasites among pregnant women attending antenatal clinic in a tertiary health institution in the Nigerian middle belt area. Abstract · Vol 19, No 2 (2012) - Articles Cryptococcal Meningitis, A Rare Opportunistic Infection In An HIV Infected Nigerian Boy: A Case ...

  10. A Venkataraman

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. A Venkataraman. Articles written in Bulletin of Materials Science. Volume 24 Issue 6 December 2001 pp 617-621 Magnetic Materials. A new combustion route to -Fe2O3 synthesis · A Venkataraman Vijay A Hiremath S K Date S D Kulkarni · More Details Abstract Fulltext PDF.

  11. Cygnus A

    NARCIS (Netherlands)

    Carilli, CL; Barthel, PD

    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

  12. S A H A R A J

    African Journals Online (AJOL)

    convenient for both auditory and visual privacy. As participants came forward to volunteer, three age-peer groups were identified in the enrolment list, guided by the participants ..... memory in South Africa.» Social Anthropology 16: 312-328. Finchilescu, G. (2002). «HIV/AIDS versus smoking-induced cancer: A comparison of ...

  13. Vitamin A

    Science.gov (United States)

    ... like cereals. Vegetarians, young children, and alcoholics may need extra Vitamin A. You might also need more if you ... your health care provider to see if you need to take vitamin A supplements. NIH: National Institutes of Health Office ...

  14. 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.

  15. 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 ...

  16. A nudez

    Directory of Open Access Journals (Sweden)

    Viviana C. Velasco Martínez

    Full Text Available O objetivo deste artigo é apresentar um mito e o seu herói. É com esse material simbólico que pretendo enfocar temas freudianos clássicos, como a sexualidade infantil, o pudor, a crueldade, o fetichismo, o exibicionismo e a castração e, assim, esboçar o contorno de uma possível fantasia neurótica inconsciente, onde a perversão encontrase em negativo.

  17. A Singh

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. A Singh. Articles written in Bulletin of Materials Science. Volume 29 Issue 3 June 2006 pp 233-238 Biomaterials. External stimuli response on a novel chitosan hydrogel crosslinked with formaldehyde · A Singh S S Narvi P K Dutta N D Pandey · More Details Abstract Fulltext ...

  18. A new

    NARCIS (Netherlands)

    Giusberti, L.; Bannikov, A.; Galazzo, F.B.; Fornaciari, E.; Frieling, J.; Luciani, V.; Papazzoni, C.A.; Roghi, G.; Schouten, S.; Sluijs, A.; Bosellini, F.R.; Zorzin, R.

    2014-01-01

    Hemipelagic dark limestones within calciturbiditic deposits at Monte Solane in the western Lessini Mountains of northern Italy yield a fish fauna dominated by stomiiforms. A minor component of the fossil assemblage is represented by a macroalgal non-calcareous flora associated with rarer terrestrial

  19. 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...

  20. A prog

    DEFF Research Database (Denmark)

    Meldgaard, Anette; Hansen, Torben Bæk; Dalsgaard, Jesper

    2009-01-01

    Background: Endoscopic carpal tunnel release with a single portal technique has been shown to reduce sick leave compared to open carpal tunnel release, claiming to be a less invasive procedure and reducing scar tenderness leading to a more rapid return to work, and the purpose of this study was t...

  1. A parapraxis in a dream.

    Science.gov (United States)

    Mahon, Eugene J

    2005-04-01

    When a parapraxis is put on display in a dream, one can only wonder what service the willful mistake is rendering to resourceful dream work. Freud taught us that anything that appears in the manifest content of a dream may well be a disguise or a distortion of a subject that originally made an anxiety-provoking, and hence short-lived, first appearance in latent dream thoughts. Dreams in dreams and jokes in dreams have been examined from this perspective (Mahon 2002a, 2002b), and this paper focuses on the appearance and meaning of a parapraxis in a dream, with the argument that seemingly casual "mistakes" are highlighted in the manifest display to cover up some latent, much more deliberate subject matter.

  2. 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....

  3. A separator

    Energy Technology Data Exchange (ETDEWEB)

    Prokopyuk, S.G.; Dyachenko, A.Ye.; Mukhametov, M.N.; Prokopov, O.I.

    1982-01-01

    A separator is proposed which contains separating slanted plates and baffle plates installed at a distance to them at an acute angle to them. To increase the effectiveness of separating a gas and liquid stream and the throughput through reducing the secondary carry away of the liquid drops and to reduce the hydraulic resistance, as well, openings are made in the plates. The horizontal projections of each opening from the lower and upper surfaces of the plate do not overlap each other.

  4. A dor

    Directory of Open Access Journals (Sweden)

    Manoel Tosta Berlinck

    Full Text Available Este trabalho relata pesquisa sobre a natureza psicopatológica da dor partindo da noção de que o humano habita na dor. Esta passa, assim, a ser um conceito-limite do humano que não consegue ultrapassá-la, apesar dos recursos farmacológicos e psíquicos disponíveis para dela se proteger. Nesta perspectiva, o corpo humano solicita uma concepção que seja capaz de levar em consideração tanto a dor física como a psíquica.

  5. A Kannan

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana. A Kannan. Articles written in Sadhana. Volume 39 Issue 2 April 2014 pp 283-302. An intelligent temporal pattern classification system using fuzzy temporal rules and particle swarm optimization · S Ganapathy R Sethukkarasi P Yogesh P Vijayakumar A Kannan · More Details Abstract Fulltext PDF.

  6. A Ganju

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science. A Ganju. Articles written in Journal of Earth System Science. Volume 117 Issue 5 October 2008 pp 575-587. Mountain range specific analog weather forecast model for northwest Himalaya in India · D Singh A Ganju · More Details Abstract Fulltext PDF. Mountain range ...

  7. A Oudhia

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. A Oudhia. Articles written in Bulletin of Materials Science. Volume 37 Issue 1 February 2014 pp 15-18. Green wet chemical route to synthesize capped CdSe quantum dots · A Oudhia P Bichpuria · More Details Abstract Fulltext PDF. In the present work, we report green ...

  8. A Sarkar

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. A Sarkar. Articles written in Bulletin of Materials Science. Volume 23 Issue 4 August 2000 pp 319-324 Polymers. An experimental investigation of electrical conductivities in biopolymers · H Mallick A Sarkar · More Details Abstract Fulltext PDF. Gum arabica obtained from acacia ...

  9. A Nandakumar

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences. A Nandakumar. Articles written in Journal of Chemical Sciences. Volume 124 Issue 3 May 2012 pp 609-624. Microwave-assisted one-pot synthesis of benzothiazole and benzoxazole libraries as analgesic agents · C Praveen A Nandakumar P Dheenkumar D Muralidharan ...

  10. A Sarangarajan

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. A Sarangarajan. Articles written in Resonance – Journal of Science Education. Volume 5 Issue 10 October 2000 pp 81-89 Classroom. On IBM's Millennial Puzzle · A Sarangarajan · More Details Fulltext PDF ...

  11. A Yazhini

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. A Yazhini. Articles written in Resonance – Journal of Science Education. Volume 23 Issue 1 January 2018 pp 57-67 General Article. Small Open Reading Frames: Tiny Treasures of the Non-coding Genomic Regions · A Yazhini · More Details Abstract Fulltext ...

  12. 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...

  13. Vitamin A

    Science.gov (United States)

    ... vitamins is to eat a wide variety of fruits, vegetables, fortified dairy foods, legumes (dried beans), lentils, and whole grains. The Food and Nutrition Board of the Institute of Medicine -- Dietary Reference ...

  14. 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...

  15. Hepatitis A

    Science.gov (United States)

    ... HealthBladder Training for Urinary IncontinenceBladder training is a way of learning to manage urinary incontinence. It helps you change your urination habits.Kidney CystsRead Article >>WomenKidney CystsAs ...

  16. 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)

  17. 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.

  18. A Alemdar

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. A Alemdar. Articles written in Bulletin of Materials Science. Volume 27 Issue 3 June 2004 pp 317-322 Surfactants. Effect of sodium dodecyl sulfate on flow and electrokinetic properties of Na-activated bentonite dispersions · E Günıster S İşçı A Alemdar N Güngör · More Details ...

  19. A89

    Directory of Open Access Journals (Sweden)

    E. Vorontsova

    2015-11-01

    Thus, hepatocyte-derived exosome population should be useful in our further understanding of the hepatic function and in the identification of components that may serve as biomarkers for hepatic alterations. These tumor-derived extracellular vesicles represent a mediator of the tumor microenvironment, and their presence in the peripheral circulation may serve as a surrogate for tumor biopsies, enabling real-time diagnosis and disease monitoring.

  20. A Marshmallow and a Song

    Science.gov (United States)

    Kenney, Susan

    2009-01-01

    Music exists in time. One cannot get to the end of the song before going through the song. Is this significant for helping children wait? And can the way we present a singing game activity intensify the delay of what might be a gratifying moment at the end of the song? In this article, the author reflects on whether music can teach delayed…

  1. 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 man...

  2. A comme... ("A" as in...).

    Science.gov (United States)

    Pstrag-Vilespy, Anne-Marie; And Others

    1982-01-01

    Presents four teaching ideas: (1) a writing activity for Level II based on photos and slides; (2) an exercise for Level II in organizing information preparatory to essay-writing; (3) an activity in grammar and creative writing for adults on an advanced level; and (4) a lesson for beginners using advertisements. (AMH)

  3. A "Network" and a "Dictum"

    DEFF Research Database (Denmark)

    Harder, Henrik

    2003-01-01

    The spatial problems encountered in urban areas, for instance "sprawl", "the fragmented town" etc. However, the critic should concentrate more on a small "network" of a few architects and planners, including an inspector (C. D. Buchanan, UK) and a single policeman (H. Alker Tripp, UK) who were...... heavily involved in the process of integrating the car as an element in the planning of urban areas and developing recommendations for road planning principles in urban areas. These road planning principles were a spin-off of a pure urban planning ideology but was primarily used to solve the massive road...... safety and accessibility problems in the urban areas created by the car. The strong ideal shared by the people within the "network" were based on the dictum "forms follow function" about mans behaviour, the car and the structure of the urban areas and was based on very little empirical research. The use...

  4. SUDOKU A STORY & A SOLVER

    Energy Technology Data Exchange (ETDEWEB)

    GARDNER, P.R.

    2006-04-01

    Sudoku, also known as Number Place, is a logic-based placement puzzle. The aim of the puzzle is to enter a numerical digit from 1 through 9 in each cell of a 9 x 9 grid made up of 3 x 3 subgrids (called ''regions''), starting with various digits given in some cells (the ''givens''). Each row, column, and region must contain only one instance of each numeral. Completing the puzzle requires patience and logical ability. Although first published in a U.S. puzzle magazine in 1979, Sudoku initially caught on in Japan in 1986 and attained international popularity in 2005. Last fall, after noticing Sudoku puzzles in some newspapers and magazines, I attempted a few just to see how hard they were. Of course, the difficulties varied considerably. ''Obviously'' one could use Trial and Error but all the advice was to ''Use Logic''. Thinking to flex, and strengthen, those powers, I began to tackle the puzzles systematically. That is, when I discovered a new tactical rule, I would write it down, eventually generating a list of ten or so, with some having overlap. They served pretty well except for the more difficult puzzles, but even then I managed to develop an additional three rules that covered all of them until I hit the Oregonian puzzle shown. With all of my rules, I could not seem to solve that puzzle. Initially putting my failure down to rapid mental fatigue (being unable to hold a sufficient quantity of information in my mind at one time), I decided to write a program to implement my rules and see what I had failed to notice earlier. The solver, too, failed. That is, my rules were insufficient to solve that particular puzzle. I happened across a book written by a fellow who constructs such puzzles and who claimed that, sometimes, the only tactic left was trial and error. With a trial and error routine implemented, my solver successfully completed the Oregonian puzzle, and has successfully

  5. A CRIANÇA EXCEPCIONAL

    Directory of Open Access Journals (Sweden)

    Maria da Penha dos Santos

    1980-01-01

    Full Text Available O autor comenta o conceito de excepcionalidade e faz considerações sobre a compreensão, aceitação e as formas de atendimento à criança excepcional. O indivíduo excepcional é considerado um ser fora do contexto, um limitado, porque vivemos numa sociedade onde todos têm um papel pré-estabelecido a exercer. Mas, o problema do excepcional é, acima de tudo, um problema humano e que atinge todo o complexo econômico-social.

  6. A Reminiscence

    Science.gov (United States)

    Gobind Khorana, H.

    1997-12-01

    Leslie Orgel and Francis Crick with Gobind Khorana in Madison, Wisconsin (December 1965). I first met Leslie at the Endicott House (MIT) in February 1964. Leslie was then spending a period of time at MIT and the occasion was a party for him. During our conversation, Leslie talked about starting some experimental work. He seemed to be particularly interested in polyphosphates and the chemical activation of small molecules (building blocks). Shortly after his move to the Salk Institute in the Fall of 1964 I visited him in January 1965. He already had a lab going. I remember meeting Jim Ferris, in particular, and John Sulston sometime later. That particular time was exciting for my research as well. We had the first results on the Genetic Code using the chemical-biochemical approach that my lab had developed. Francis Crick was also at the Salk Institute during the time of my visit. Both Leslie and Francis were very excited by my results and they began to ask a lot of questions and gave me a whole lot of suggestions about further experiments. In fact, my thinking and planning of things that we were doing were so scrutinized and clarified during these discussions that, it seemed to me, my own group had only to turn out all the experiments that were needed. These interactions with Francis and Leslie continued intensively throughout that year and later. In fact, both Leslie and Francis accepted my invitation to Madison in December 1965 for more discussions. Since those early days of the Salk Institute, I have made numerous visits over the years to Leslie and his research group. It has always been very exciting to learn about the many discoveries bearing on chemical evolution that have unfolded from Leslie's research group. In addition, I have always benefitted from the insightful comments that Leslie invariably provided on my own research. I look forward to our continued interactions and friendship in the future. Leslie, A Happy Birthday!

  7. A Aspirina e a Asma

    Directory of Open Access Journals (Sweden)

    K.S. Babu

    2001-03-01

    Full Text Available RESUMO: A aspirina é não só o fannaco me1hor estudado em todo o mundo, como o mais frequentemente uti1izado em todos os tempos. Alem das suas propriedades como analgesico e antipiretico, o acido acetilsalicflico (AAS e urn inibidor da agregação plaquetária, o que the confere urn papel essencial na profilaxia do tromboembolismo e na prevenção dos acidentes cardio e cerebro-vasculares.A associação da sensibilidade á aspirina, com a asma e a polipose nasal, descrita pela primeira vez por Femand Widal e colaboradores, constitui a trfade da “Asma lnduzida pela Aspirina” (AlA e refere-se ao desenvolvimento de urn quadro de broncoconstrição em indivfduos asmaticos após ingestao de aspirina. Nestes doentes, os sintomas agudos sobrepõem-se ao quadro clfnico de asma crónica grave. As crises de asma podem ser desencadeadas por pequenas quantidades de AAS ou de outros anti-inflamatórios nao ester6ides (AINE’ s.A prevalência da AIA na comunidade é incerta, mas os doentes com AIA constituem 10 a 20% da popula9ao asmatica, sendo a AIA mais frequente nas mulheres. Os autores deste trabalho fazem uma revisão teórica da AIA, descrevendo a apresentação clfnica, os mecanismos patogenicos, o diagnóstico e o tratamento deste síndrome.A asma e uma doença inflamatória crónica das vias aéreas. Neste estado de inflamação continua, a exposiyao aaspirina provoca no subgrupo de doentes com AIA uma acentuayao temporaria do processo inflamat6rio, que conduz á exacerbayao da asma. Embora assemelhando-se as reacçães de hipersensibilidade imediata, a AIA nao parece ser mediada por mecanismos dependentes da IgE, daí estas reacçães scrcm dcsignadas de “anafilactóides”.A hipersensibilidade à aspirina parece antes ser mediada por um desvio da via metab6lica do acido araquidónico no sentido da produção excessiva de leucotrienos, por

  8. 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...

  9. A GRAÇA LIBERTADORA

    Directory of Open Access Journals (Sweden)

    C. L. Bins

    1978-01-01

    Full Text Available C L . Bins presents some considerations about the book of Leonardo Boff: A Graça Libertadora no Mundo. (The freeing Grace in the world. Recognizing the values of this study, the author discusses, mainly, the way the roviter interprets the central reality of christianism: the living presence of the Trinity in the soul of the faithful and the divine filiation of man.

  10. 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.

  11. A comparison

    African Journals Online (AJOL)

    2015-10-26

    Oct 26, 2015 ... He was the student of Socrates and the teacher of Aristotle, 427–347. BCE; viewed 24 August 2014, from ... For Aristotle, a student of Plato, the true purpose of human life is achieved in ...... Goodenough, E.R., 1963, An introducfion to Philo Judaeus, Barnes & Noble, New York. Goodenough, E.R., 1969, By ...

  12. A. Ramesh

    Indian Academy of Sciences (India)

    174 Research Note. Genetic study of scheduled caste populations of Tamil Nadu · M. Vijaya S. Kanthimathi A. Ramesh · More Details Fulltext PDF. Volume 87 Issue 2 August 2008 pp 175-179 Research Note. Genetic study of Dravidian castes of ...

  13. A due

    DEFF Research Database (Denmark)

    covering the period from the Middle Ages to the present day - give their voice in the honouring of the two scholars for their musical scholarship. As it may be seen from the table of contents, the publication covers a broad range both in time and in topics, which are all included in the scholarly sphere...

  14. Vitamin A

    Science.gov (United States)

    ... causing low blood levels in some people. Several synthetic forms of vitamin A are used in prescription medicines. Examples are the psoriasis treatment acitretin (Soriatane®) and bexarotene (Targretin®), used to treat the skin effects of T-cell lymphoma. Taking these medicines ...

  15. Bisphenol A

    Science.gov (United States)

    ... also contain BPA. BPA is used in the recycling of thermal paper, such as receipts, self-adhesive labels, and fax paper. It is also used to make polyvinyl chloride plastics. Plastic products made with BPA will have a #7 recycling symbol on them or contain the letters “PC” ...

  16. Hepatitis A

    Science.gov (United States)

    ... 간염: 아시아 또는 태평양군도 계 미국인의 숙지 사항 (Korean) Hepatitis B: Mga Tip para sa mga Amerikano ... hepatitis A virus typically spreads through contact with food or water that has been contaminated by an ...

  17. A novel

    NARCIS (Netherlands)

    K.L.S. Chatalic (Kristell); J. Veldhoven-Zweistra (Joke); M. Bolkestein (Michiel); S. Hoeben (Sander); G.A. Koning (Gerben); O.C. Boerman (Otto); M. de Jong (Marion); W.M. van Weerden (Wytske)

    2015-01-01

    textabstractProstate-specific membrane antigen (PSMA) is overexpressed in prostate cancer (PCa) and a promising target for molecular imaging and therapy. Nanobodies (single-domain antibodies, VHH) are the smallest antibody-based fragments possessing ideal molecular imaging properties, such as high

  18. Skovsted, A

    Indian Academy of Sciences (India)

    G. herbaceum war. Wightictinct G. herbaceut and var. (fricanct. O 1027 A.L.E. Il Guza,. O7 Moamba, H2 Iraqi. 3 N289. H5 N454. (iii) Species with 52 Sonatic chronosomes. (9) New World cottons including all species with n = 26. Harland's classification has been followed throughout (1932b). The types generally used are ...

  19. Appendix A

    DEFF Research Database (Denmark)

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

    1999-01-01

    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...

  20. 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

  1. 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

  2. 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.

  3. A, a Brominated Flame Retardant

    Directory of Open Access Journals (Sweden)

    Tomomi Takeshita

    2013-01-01

    Full Text Available Tetrabromobisphenol A (TBBPA, a brominated flame retardant, has been found to exacerbate pneumonia in respiratory syncytial virus- (RSV- infected mice. We examined the effect of Brazilian propolis (AF-08 on the exacerbation of RSV infection by TBBPA exposure in mice. Mice were fed a powdered diet mixed with 1% TBBPA alone, 0.02% AF-08 alone, or 1% TBBPA and 0.02% AF-08 for four weeks and then intranasally infected with RSV. TBBPA exposure increased the pulmonary virus titer and level of IFN-γ, a representative marker of pneumonia due to RSV infection, in the lungs of infected mice without toxicity. AF-08 was significantly effective in reducing the virus titers and IFN-γ level increased by TBBPA exposure. Also, AF-08 significantly reduced proinflammatory cytokine (TNF-α and IL-6 levels in the lungs of RSV-infected mice with TBBPA exposure, but Th2 cytokine (IL-4 and IL-10 levels were not evidently increased. Neither TBBPA exposure nor AF-08 treatment affected the anti-RSV antibody production in RSV-infected mice. In flow cytometry analysis, AF-08 seemed to be effective in reducing the ratio of pulmonary CD8a+ cells in RSV-infected mice with TBBPA exposure. TBBPA and AF-08 did not exhibit anti-RSV activity in vitro. Thus, AF-08 probably ameliorated pneumonia exacerbated by TBBPA exposure in RSV-infected mice by limiting excess cellular immune responses.

  4. A Leitura e a Tela

    Directory of Open Access Journals (Sweden)

    Sérgio Luiz Alves da Rocha

    2015-09-01

      ABSTRACT This paper is a result of a doctoral research, in a public high school in Rio de Janeiro. The main objective of this work was to discuss - with teachers and students - some topics related to their conceptions and practices about reading, throughout pictures that were taken by them during the research. The different ideas about reading, the link between literary reading and other kinds of reading with "new technologies", the function of school, motivating - or not - the access to different places of reading, were some of the topics discussed throughout the research. During the research I analyzed reading as a cultural practice, as proposed by cultural history. The present text emphasizes a part of this discussion focusing on the relationship between image, reading and the school. Keywords: Lecture; Youth; Image; School; Television. RESUMEN Este trabajo es el resultado de una investigación doctoral , en una escuela secundaria pública en Río de Janeiro. El principal objetivo de este trabajo fue discutir - con maestros y estudiantes - algunos temas relacionados con sus concepciones y prácticas acerca de la lectura , a lo largo de las imágenes que fueron tomadas por ellos durante la investigación. Las diferentes ideas acerca de la lectura, la relación entre la lectura literaria y otros tipos de lectura con "nuevas tecnologías", la función de la escuela, motivando - o no - el acceso a los diferentes lugares de lectura, fueron algunos de los temas tratados a lo largo de la investigación. Durante la investigación la lectura fue tratada como práctica cultural, según lo propuesto por la historia cultural. El presente texto hace trata de una parte de esta discusión que se centra en la relación entre la imagen, la lectura y la escuela . Palabras Clave: Lectura; Juventud; Imagen; Escuela; Televisión.   Referências ADORNO, T.W. ; HORKHEIMER, M. A indústria cultural: o esclarecimento como mistificação das massas. In ______. Dialética do

  5. A LDB e a psicologia

    Directory of Open Access Journals (Sweden)

    Oswaldo H. Yamamoto

    Full Text Available Este estudo discute as implicações para a formação acadêmica e para o exercício profissional do psicólogo, da aprovação da Lei de Diretrizes e Bases da Educação Nacional (LDB. São pontuados alguns dos pressupostos subjacentes à lei, os aspectos principais do texto legal e algumas de suas decorrências, como a regulamentação dos cursos seqüenciais e diretrizes curriculares.

  6. 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.

  7. 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.

  8. On a question of A. Balog

    OpenAIRE

    Shkredov, Ilya D.

    2015-01-01

    We give a partial answer to a conjecture of A. Balog, concerning the size of AA+A, where A is a finite subset of real numbers. Also, we prove several new results on the cardinality of A:A+A, AA+AA and A:A + A:A.

  9. A novel HLA-A allele: A*0257.

    Science.gov (United States)

    García-Ortiz, J E; Cox, S T; Sandoval-Ramirez, L; Little, A M; Marsh, S G E; Madrigal, J A; Argüello, J R

    2004-01-01

    A novel human leucocyte antigen-A*02 (HLA-A*02) allele was detected by reference strand-mediated conformation analysis (RSCA) of a DNA sample from a Tarahumara individual. Direct sequencing of HLA-A locus polymerase chain reaction products identified a mutation in one of the alleles. Cloning and sequencing confirmed the presence of a new allele, A*0257 which differed from A*0206 by two nucleotides at positions 355 and 362, inducing changes in residues 95 and 97, respectively, within the peptide-binding site. Those changes suggest that allele A*0257 may have resulted from an intralocus recombination event.

  10. A method of installing a reactor container

    International Nuclear Information System (INIS)

    Hayashi, Kenji; Murakawa, Hisao.

    1975-01-01

    Object: To achieve exact installation of a reactor container at a site. Structure: A pole is set upright at the center of a cylindrical base portion, a plurality of beams are disposed around the pole in a radial fashion to form a cone, a plurality of steel plates are mounted successively around the cone through a ring, and the steel plates are welded to each other to assemble and install a reactor container at the same time. (Kamimura, M.)

  11. Hyphal formation of Candida albicans is controlled by electron transfer system

    International Nuclear Information System (INIS)

    Watanabe, Toshihiko; Ogasawara, Ayako; Mikami, Takeshi; Matsumoto, Tatsuji

    2006-01-01

    Most Candida albicans cells cultured in RPMI1640 medium at 37 deg. C grow in hyphal form in aerobic conditions, but they grow in yeast form in anaerobic conditions. The hyphal growth of C. albicans was inhibited in glucose-deficient conditions. Malonic acid, an inhibitor of succinate dehydrogenase, enhanced the yeast proliferation of C. albicans, indicating that the hyphal-formation signal was derived from the glycolysis system and the signal was transmitted to the electron transfer system via the citric acid cycle. Thenoyl trifluoro acetone (TTFA), an inhibitor of the signal transmission between complex II and Co Q, significantly inhibited the hyphal growth of C. albicans. Antimycin, KCN, and oligomycin, inhibitors of complex III, IV, and V, respectively, did not inhibit the hyphal growth of C. albicans. The production of mRNAs for the hyphal formation signal was completely inhibited in anaerobic conditions. These results indicate that the electron transfer system functions upstream of the RAS1 signal pathway and activates the expression of the hyphal formation signal. Since the electron transfer system is inactivated in anaerobic conditions, C. albicans grew in yeast form in this condition

  12. A.A., constructivism, and reflecting teams.

    Science.gov (United States)

    Nevels, B

    1997-12-01

    Numerous studies and clinical anecdotes reveal a relationship between attendance at A.A. meetings and/or degree of involvement in A.A. and maintenance of sobriety. Hypotheses as to how A.A. and/or the A.A. meeting is helpful to its members have ranged from a focus on factors common to all therapy groups, to aspects of A.A. "treatment" which are behavioral in nature. Presented here is another way of understanding A.A.'s effectiveness within the frame of more recent, constructivistic approaches to family therapy. In particular, the A.A. topic meeting is compared to the reflecting team concept of Tom Anderson.

  13. A Stroke Mimic: A Case Report

    Directory of Open Access Journals (Sweden)

    Annia Martínez Rivas

    2016-03-01

    Full Text Available Diseases mimicking a stroke are a major health problem for a large number of hospitals. This paper aims at presenting a disease that has a stroke-like presentation. The case of a 46-year-old man admitted to the stroke unit with a clinical and radiological diagnosis of cerebral infarction is presented. The patient developed fever and a serious deterioration of consciousness. Changes on computed tomography consistent with a brain abscess were observed. Broad-spectrum antibiotics were administered and a follow-up tomography was performed. Once the treatment was completed, the clinical and radiological suspicion of a brain abscess was confirmed.

  14. A Bíblia e a cultura

    OpenAIRE

    Gonçalves, Joaquim Cerqueira

    2005-01-01

    1. Pensar a Bíblia 2. A Bíblia e a cultura 3. Bíblia, cultura e linguagem 4. A revelação 5. O possível, o irrecusável e a Escritura 6. A Bíblia e as culturas no horizonte da ontologia 7. Jesus Cristo e a comunidade: manifestação ontológica 8. A religião cristã e as culturas

  15. A Slot Machine, A Broken Test Tube

    Indian Academy of Sciences (India)

    IAS Admin

    It must be a study of the author's personality, a dissection of action and motives, a revelation of the self'. Luria has successfully done exactly this. When someone speaks of a Nobel Prize, the immediate feeling we get is awe and admira- tion. A Nobel Prize-winner is considered as someone who lives in a different realm alto-.

  16. A section of a spiral coal chute

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtin, V.N.; Gorodilov, N.N.

    1981-01-01

    A section of a spiral coal chute includes a housing with support brackets. It differs in that to decrease the amount of work necessary for assembly, each support bracket is made with a guide slot and equipped with a pull-out cantilever in the shape of a fork which covers the slot from the lateral sides.

  17. Can a String's Tension Exert a Torque on a Pulley?

    Science.gov (United States)

    Krause, Dennis E.; Sun, Yifei

    2011-01-01

    A typical textbook problem in rotational dynamics involves calculating the angular acceleration of a massive pulley due to a string, such as in the example shown in Fig. 1. The string is assumed to be massless and to move without slipping over the pulley, which is mounted on a frictionless axle. If T[subscript L] and T[subscript R] are the…

  18. Constructing a Parser for a given Deterministic Syntax Graph: A ...

    African Journals Online (AJOL)

    This article aimed at developing a syntax graph into a parser capable of being transformed into a translator, in this circumstance a complier. The rules of graph to program translation were laid down and followed religiously to arrive at the required program. These rules make provisions for various constructs or structures of ...

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

    OpenAIRE

    R Waxman; K Khorasani; A Lenny; S Bhalerao

    2009-01-01

    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...

  20. A batuta da morte a orquestrar a vida

    Directory of Open Access Journals (Sweden)

    Altair Macedo Lahud Loureiro

    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.

  1. Blood Test: Immunoglobulin A (IgA)

    Science.gov (United States)

    ... Blood Test: Immunoglobulin A (IgA) What's in this article? What It Is Why It's Done Preparation The Procedure What to Expect Getting the Results Risks Helping Your Child If You Have Questions Print en español Análisis de sangre: inmunoglobulina A (IgA) What It Is An IgA ...

  2. Charging a Capacitor with a Photovoltaic Module

    Science.gov (United States)

    Aguilar, Horacio Munguía; Maldonado, Rigoberto Franco; Navarro, Luis Barba

    2017-01-01

    Charging a capacitor with a photovoltaic module is an experiment which reveals a lot about the modules characteristics. It is customary to represent these characteristics with an equivalent circuit whose elements represent its physical parameters. The behavior of a photovoltaic module is very similar to that of a single cell but the electric…

  3. A psychological profile of a serial killer: a case report.

    Science.gov (United States)

    Dogra, T D; Leenaars, Antoon A; Chadha, R K; Manju, Mehta; Lalwani, Sanjeev; Sood, Mamta; Lester, David; Raina, Anupuma; Behera, C

    2012-01-01

    Serial killers have always fascinated society. A serial killer is typically defined as a perpetrator who murders three or more people over a period of time. Most reported cases of serial killers come from the United States and Canada. In India, there are few reported cases. We present, to the best of our knowledge, the first Indian case in the literature. The present case is of a 28-year-old man, Surinder Koli. The Department of Forensic Medicine & Toxicology, All India Institute of Medical Sciences, New Delphi handled the forensic study. We present a most unique psychological investigation into the mind of a serial killer.

  4. Scarlet Fever: A Group A Streptococcal Infection

    Science.gov (United States)

    ... Submit What's this? Submit Button Past Emails Scarlet Fever: A Group A Streptococcal Infection Language: English (US) ... and 15 years old. People Can Spread Scarlet Fever Germs to Others Group A strep bacteria can ...

  5. A farmer becomes a social pedagogue

    DEFF Research Database (Denmark)

    Mellon, Karsten

    2016-01-01

    for bachelor programmes. This article examines the case of a woman named Amy, a mature, nontraditional university college student who becomes a social pedagogue. Because of severe allergies, Amy had to quit her job as a farmer and began to study to become a social pedagogue. Becoming a social pedagogue...... is a tremendously complex process that involves taking on a new professional identity and acquiring new skills. In order to ascertain the extent of this complexity, this article uses a psychosocietal approach derived from a Danish/German life history research approach. This article offers a brief presentation...... of the theoretical and methodological framework applied before analysing the process Amy undergoes to become a social pedagogue. The analysis demonstrates that this type of significant career change is demanding and, for Amy, filled with feelings of ambivalence and defensiveness....

  6. Towards A Regional Science Academy: A Manifesto

    Directory of Open Access Journals (Sweden)

    Karima Kourtit

    2016-04-01

    Full Text Available This Manifesto provides a joint proposal to create a Regional Science Academy as a think-tank support platform for a strategic development of the spatial sciences. The Regional Science Academy is a strategic spatial knowledge catalyst: it acts as a global intellectual powerhouse for new knowledge network initiatives and scholarly views on regions and cities as vital centrepieces of interconnected spatial systems. This contribution highlights its role and presents various activity plans.

  7. A pedagoxía hospitalaria

    OpenAIRE

    Grau Rubio, Claudia

    2001-01-01

    A pedagoxía hospitalaria e a Educación Especial teñen numerosos puntos en común, en canto que as dúas supoñen unha acción multidisciplinaria e consideran que as dificultades de aprendizaxe e os problemas de saúde non poden ser abordados exclusivamente desde a Pedagoxía ou a Medicina.

  8. A case for a code of ethics.

    Science.gov (United States)

    Bayliss, P

    1994-03-01

    Ethical dilemmas in business and health have become a familiar topic over recent times. Doubts remain, however, as to whether a code should be produced and the recently issued IHSM consultation paper argues the case for "a statement of primary values" rather than a code of ethics. In a second article on the subject, Paul Bayliss examines the importance of having a code, looks at some of the contextual issues and suggests an approach to producing one.

  9. A Disease or Not a Disease? Aging As a Pathology.

    Science.gov (United States)

    Gladyshev, Timothy V; Gladyshev, Vadim N

    2016-12-01

    The debate on the relationship between aging and disease is centered on whether aging is a normal/natural/physiological process or it represents a pathology. Considering this relationship from medical, molecular, social, and historical perspectives, we argue that aging is neither a disease, nor a non-disease. Instead, it combines all age-related diseases and their preclinical forms, in addition to other pathological changes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. A Higher Education--A Polemic (For a Change)

    Science.gov (United States)

    Peters, Lloyd

    2015-01-01

    The BBC Radio 4 comedy-drama "A Higher Education" was written in 1999 to present a satire of a dysfunctional and cash-strapped university (Northfield) led by the egotistical and amoral Head of Drama, Don Crookfield (played by Rik Mayall). For those of us passionately engaged in the provision of higher education today, the satire also…

  11. A ROBOT AND A METHOD OF CONTROLLING A ROBOT

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to a robot comprising a horizontal or horizontally slanted transparent experiment layer being adapted to support items at arbitrary positions on or in the experiment layer, and a moveable sensor arranged below the transparent experimental layer said sensor being...

  12. A rose is a rose is a rose

    NARCIS (Netherlands)

    Vinkers, Christiaan H.

    2017-01-01

    Over a century ago in 1913, the poet Gertrude Stein wrote these famous words: sometimes things are just what they are. There has been a recent debate centred around the question whether or not schizophrenia exists. Is there a brain disease that can be called schizophrenia? What difference does it

  13. A rose is a rose is a rose’

    NARCIS (Netherlands)

    Vinkers, C H

    2017-01-01

    Over a century ago in 1913, the poet Gertrude Stein wrote these famous words: sometimes things are just what they are. There has been a recent debate centred around the question whether or not schizophrenia exists. Is there a brain disease that can be called schizophrenia? What difference does it

  14. Zassenhaus conjecture for A6 A6 A6

    Indian Academy of Sciences (India)

    It remains not only unsolved but also lacking in plausible means of either proof or counter-example. Only a few non-solvable groups G are known to satisfy (ZC1); in this note, the conjecture is verified for the alternating group A6. In 1988, Luthar and Passi [17] started investigations in this field when dealing with A5, thereby ...

  15. A model of a social chatbot

    NARCIS (Netherlands)

    Augello, Agnese; Gentile, Manuel; Weideveld, Lucas; Dignum, Frank

    2016-01-01

    Traditional chatbots lack the capability to correctly manage conversations according to the social context. However a dialogue is a joint activity that must consider both individual and social processes. In this work we propose a model of a social chatbot able to choose the most suitable dialogue

  16. A microfluidic device with a diffusion barrier

    DEFF Research Database (Denmark)

    2014-01-01

    with a common junction via micro channels. To enable amplification of DNA, e.g. by MDA, the device comprises a diffusion barrier at each inlet configured to increase the pressure threshold for a reagent to cross the resistor. The invention further provides a method of mixing liquid reagents by use of the device...

  17. S.A.A.F. IN KOREA

    African Journals Online (AJOL)

    UN~CCr- .\\. '\\ \\. FOOTNOTE. Mr Dermot Michael Moore, MA (History) is a senior Lecturer of. History at the University of Fort Hare and he is also a Major in the. SAIC (Comdos). He is currently doing research on the SAAF in. Korea for a D Litt et Phil Degree at Unisa. References. 1. J. W. Pratt, A History of United States Foreign ...

  18. 1955-IJBCS-Article-Ajayi A A

    African Journals Online (AJOL)

    hp

    2Department of Microbiology, Faculty of Information Technology and Applied Sciences,. Lead City University, Ibadan, Nigeria. ... chevalieri in a defined medium. A. chevalieri was grown in a synthetic medium containing starch as the sole ... modified dextrinogenic assay method of. Pfueller and Elliot (1969) involving a direct.

  19. Ventana a la farmacología

    Directory of Open Access Journals (Sweden)

    Facultad de Medicina Revista

    1995-10-01

    Full Text Available Medicamentos de alto riesgo fetal /  Oscar Fabio Ramos -- Reacciones adversas a medicamentos en neonatos de riesgo /  Oscar Armando García Vega y Miguel Eduardo Martínez  -- Reacciones adversas a los medicamentos ¿El médico debe informarlas? / Oscar Armando García Vega y Miguel Eduardo Martínez

  20. A cyclotron as a mass spectrometer

    International Nuclear Information System (INIS)

    Bricault, P.; Auger, G.; Bajard, M.; Baron, E.; Bibet, D.; Chabert, A.; Ferme, J.; Gaudart, L.; Joubert, J.; Audi, G.; Fifield, K.

    1992-01-01

    Taking advantage of the system of coupled cyclotrons at GANIL, a method has been developed for mass measurements with a cyclotron. The secondary nuclei are produced in a target located between the two separated sector cyclotrons by the interaction of a beam coming from the first cyclotron. They are subsequently accelerated in the second cyclotron. The prior tuning of this cyclotron for those very low intensity is accomplished using a beam having the same q/A ratio at the right velocity. For fine tuning, a probe inside one sector of the cyclotron has been developed. This new probe is described and first results are presented. (author) 7 refs., 4 figs

  1. When is a physician network a group?

    Science.gov (United States)

    Marr, T J; Zismer, D K

    1998-01-01

    Developing a network of physicians into a high-performing group requires a cultural transformation. The hallmarks, as well as the obstacles, to achieving this are reviewed by two experienced consultants. The requirements of highly successful physician organizations range from sharing a common mission, vision, and values to developing an effective infrastructure to having visionary leadership. Barriers to successful physician groups include a lack of clarity of purpose and goals, lack of quality standards, and an absence of shared learning. A blueprint on how to become a successful physician group is provided.

  2. Remembering a Shape -- Assembling a Memory

    Science.gov (United States)

    Zeravcic, Zorana; Murugan, Arvind; Brenner, Michael; Leibler, Stanislas

    2014-03-01

    Recently we have been developing a new connection between self-assembly and neural networks, where a multi-component particle system with specified interaction rules between its components is mapped onto a multi-state Hopfield neural network model. Within this framework, a fixed interaction pattern of neurons representing a ``memory'' maps to particle interactions encoding a certain structure. Properties of neural networks motivate new types of questions: Can the interaction energies of particles code for multiple structures at the same time? Can stored structures be retrieved by throwing in a nucleation seed (i.e., a small assembly of particles) and have it complete into the desired stored structure? Can we define a capacity, i.e., a maximal number of structures that can be retrieved with limited error? We investigate these questions using numerical simulations of different types of building blocks with short-range interactions.

  3. A search for a new gauge boson A'

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Eric L. [College of William and Mary, Williamsburg, VA (United States)

    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+e-+ 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 α'/αfs > 6 × 10-8 to electrons in the mass range 65MeV < mass A' < 550MeV. The experiment will study e+e- production off an electron beam incident on a high-Z target in Hall A at Jefferson Lab. The e- and e+ will be detected in the High Resolution Spectrometers (HRSs). The invariant mass spectrum of the e+e- 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+e-reaction, and set an upper limit of {alpha}'/{alpha}{sub fs} ~ 10-6.

  4. A sign on a tree: A case for 'public knowledge'

    OpenAIRE

    Ma, Lai

    2015-01-01

    Can information be objective and/or subjective? Based on Patrick Wilson’s notion of public knowledge and a story of a sign on a tree, this paper argues that private information is not the same as subjective information, and that the very communicative process of making information makes information objective. It also argues that the objective sense of information—public knowledge—has been and will be most relevant to information science, hence questions concerning collective responsibility in...

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

    OpenAIRE

    Kateřina; Daniela; Martina

    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...

  6. 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...

  7. The Generalized A* Architecture

    OpenAIRE

    Felzenszwalb, P. F.; McAllester, D.

    2011-01-01

    We consider the problem of computing a lightest derivation of a global structure using a set of weighted rules. A large variety of inference problems in AI can be formulated in this framework. We generalize A* search and heuristics derived from abstractions to a broad class of lightest derivation problems. We also describe a new algorithm that searches for lightest derivations using a hierarchy of abstractions. Our generalization of A* gives a new algorithm for searching AND/OR graphs in a bo...

  8. A Few Reflections on A Numerate Life

    Directory of Open Access Journals (Sweden)

    John Paulos

    2018-01-01

    Full Text Available John Allen Paulos. A Numerate Life: A Mathematician Explores the Vagaries of Life, His Own and Probably Yours (Amherst, NY: Prometheus Books, 2015. 200 pp. ISBN 978-1633881181. This piece briefly introduces and excerpts A Numerate Life: A Mathematician Explores the Vagaries of Life, His Own and Probably Yours, written by John Allen Paulos and published by Prometheus Books. The book shares observations on life�many biographical�from the perspective of a numerate mathematician. The excerpt uses basic statistical reasoning to explore why we should expect that being odd is a most normal experience.

  9. A Feasibility study of a mining business

    Directory of Open Access Journals (Sweden)

    Cehlár Michal

    2001-06-01

    Full Text Available The economic evaluation of a project requires a great deal of diverse information to be brought together in one place. The greatest concern is that there will be an error by omission, so it is useful to have a detailed list of what one needs to know in order to make a thorough evaluation.There are various of detail required at the different stages of evaluation in the project, from the "quick and dirty" overview to the pre-feasibility study, through a full detailed feasibility study, to a due diligence review. This list addresses most of the economic variables in project and can be used at all levels of studies. Its purpose is to identify a variable or issue and to raise a question, which the review can pursue in more detail using an increasingly more comprehensive checklist for each topic. While developed from the point of view of a new project, this list is equally valid for an ongoing operation.A feasibility study is defined as an assessment of all aspects of a project including technical, infrastructural, environmental, social, legislative and commercial factors, which is sufficiently detailed to support a decision on the implementation. Each project has an associated level of risk. For a proposed investment to increase the value of a firm's stock, it should have a higher expected rate of return than shareholders require for assuming that risk. Since investors demand for a higher potential returns from a riskier project, the cost of capital depends on the venture's risk.

  10. 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.

  11. Geminiviruses: a tale of a plasmid becoming a virus

    Directory of Open Access Journals (Sweden)

    Krupovic Mart

    2009-05-01

    Full Text Available Abstract Background Geminiviruses (family Geminiviridae are small single-stranded (ss DNA viruses infecting plants. Their virion morphology is unique in the known viral world – two incomplete T = 1 icosahedra are joined together to form twinned particles. Geminiviruses utilize a rolling-circle mode to replicate their genomes. A limited sequence similarity between the three conserved motifs of the rolling-circle replication initiation proteins (RCR Reps of geminiviruses and plasmids of Gram-positive bacteria allowed Koonin and Ilyina to propose that geminiviruses descend from bacterial replicons. Results Phylogenetic and clustering analyses of various RCR Reps suggest that Rep proteins of geminiviruses share a most recent common ancestor with Reps encoded on plasmids of phytoplasmas, parasitic wall-less bacteria replicating both in plant and insect cells and therefore occupying a common ecological niche with geminiviruses. Capsid protein of Satellite tobacco necrosis virus was found to be the best template for homology-based structural modeling of the geminiviral capsid protein. Good stereochemical quality of the generated models indicates that the geminiviral capsid protein shares the same structural fold, the viral jelly-roll, with the vast majority of icosahedral plant-infecting ssRNA viruses. Conclusion We propose a plasmid-to-virus transition scenario, where a phytoplasmal plasmid acquired a capsid-coding gene from a plant RNA virus to give rise to the ancestor of geminiviruses.

  12. Why See a Gynecologist?

    Science.gov (United States)

    ... Seeing the doctor Why see a gynecologist? Why see a gynecologist? Going to see a gynecologist — ... go? What will happen at the visit? Why see a gynecologist? top Seeing a gynecologist can: Help ...

  13. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Child First See a Dentist? The History of Dental Advances Why is Oral Health Important for Men? What is Baby Bottle Tooth Decay? Learn what those dental words mean. The Life of a Tooth Home | ...

  14. Broadcasting a message in a parallel computer

    Science.gov (United States)

    Berg, Jeremy E [Rochester, MN; Faraj, Ahmad A [Rochester, MN

    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.

  15. SI Units? A Camel is a Camel.

    Science.gov (United States)

    Adamson, Arthur W.

    1978-01-01

    This paper is a summary of remarks made at a recent symposium on new directions in the teaching of physical chemistry. The author takes exception to the claims made for the International System of Units (SI). (HM)

  16. What a difference a week makes

    CERN Multimedia

    2006-01-01

    "Just days after celebrations at a Chatteris factory to mark the success of a £5 million contract, redundancy notices were handed out to some of the workers who had seen it through to completion." (1 page)

  17. A Cultural Sexuality or a Sexual Culture?

    NARCIS (Netherlands)

    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.

  18. 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......’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 development project’s nature, which according to Simon [3] is ill-structured, explorative and pragmatic....... In 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...

  19. Generalizing a study of a rotating rod carrying a collar

    International Nuclear Information System (INIS)

    Campos, I; Del Valle, G; Hernandez, M G; Jimenez, J L

    2010-01-01

    The present work is a generalization of the work of Ribberfors and Reitz (2000 Eur. J. Phys. 21 151-7). These authors study a system consisting of a collar that is restricted to move in a path defined by a rod of some prescribed form which passes through the collar. We generalize the analysis of this system by means of canonical treatment. We show in this way that this excellent example can also be used in advanced courses on mechanics to show the power of the methods of analytical mechanics. We have that the present treatment of this example will be useful for advanced undergraduate and graduate students as well as for the teachers of these courses on classical mechanics. (letters and comments)

  20. 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.

  1. Giuseppe Moscati: a man, a physician and a scientist.

    Science.gov (United States)

    Ponti, Giovanni; D'Onofrio, Felice; Ruini, Cristel; Muscatello, Umberto; Tomasi, Aldo

    2015-01-01

    The life of Giuseppe Moscati (1880-1927) as a man, as a physician and as a scientist may be framed within the cultural climate of Positivism, which spread over the last years of the 19th century and the beginning of the 20th Century. His activity contributed to patients' care improvement; in addition to meticulous drug regimens, he also prescribed a methodology of spiritual care, involving meditation and self-control as part of an holistic approach to healthcare. Our review deals with his published researches, highlighting the innovative findings on the juvenile diabetes treatment and extensive clinical changes consequent upon nephritis. This extraordinary man put considerable emphasis on primary care and holistic health in Italy, pioneering a new patient-centred, and holistic approach to medicine.

  2. A review of onabotulinumtoxinA (Botox).

    Science.gov (United States)

    Lorenc, Z Paul; Kenkel, Jeffrey M; Fagien, Steven; Hirmand, Haideh; Nestor, Mark S; Sclafani, Anthony P; Sykes, Jonathan M; Waldorf, Heidi A

    2013-03-01

    OnabotulinumtoxinA was introduced to the US market in 2002 as the first botulinum toxin type A (BoNTA) approved for facial aesthetics. This article provides an overview of onabotulinumtoxinA's uses and indications as well as safety and efficacy data. As with other BoNTA products, onabotulinumtoxinA is generally well tolerated. Consideration is also given to clinical applications of the product. Information on handling, storage, and dosing is provided.

  3. 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......, a small consulting company from Costa Rica, is using action learning to implement COBIT in the financial sector in Costa Rica....

  4. A Masked Photocathode in a Photoinjector

    OpenAIRE

    Qiang, Ji

    2011-01-01

    In this paper, we propose a masked photocathode inside a photoinjector for generating high brightness electron beam. Instead of mounting the photocathode onto an electrode, an electrode with small hole is used as a mask to shield the photocathode from the accelerating vacuum chamber. Using such a masked photocathode will make the replacement of photocathode material easy by rotating the photocathode behind the electrode into the hole. Furthermore, this helps reduce the dark current or seconda...

  5. 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.

  6. A designed experiment in a continuous process

    OpenAIRE

    Vanhatalo, Erik; Vännman, Kerstin; Hyllander, Gunilla

    2007-01-01

    This paper discusses the design and analysis of an experiment performed in a continuous process (CP). A full factorial design with replicates is used to test three types of pellets on two levels of a process variable in an experimental blast furnace process. Issues and considerations concerning the experimental design and analysis are discussed. For example, an adaptive experimental design is used. We propose a multivariate approach to the analysis of the experiment, in form of principal comp...

  7. Transforming a foundation into a cooperative

    Directory of Open Access Journals (Sweden)

    Juan Ramón Manzano Malaxechevarría

    2013-12-01

    Full Text Available The author charts a path between entities that meet needs in the general interest such as foundations and others which are neither entities of general interest nor have purely mercantile legal personality such as cooperatives. Transforming a foundation into a cooperative calls for a broad interpretation of the principle of free will that the legislation wishes to foster.Received: 12.02.2013Accepted: 20.04.2013

  8. A Random Walk on a Circular Path

    Science.gov (United States)

    Ching, W.-K.; Lee, M. S.

    2005-01-01

    This short note introduces an interesting random walk on a circular path with cards of numbers. By using high school probability theory, it is proved that under some assumptions on the number of cards, the probability that a walker will return to a fixed position will tend to one as the length of the circular path tends to infinity.

  9. Sustainable Competence: A Study of a Bank

    Science.gov (United States)

    Hagstrom, Tom; Backstrom, Tomas; Goransson, Susanna

    2009-01-01

    Purpose: Decentralization and company cultures have emerged to master increasing external flexibility, as in a competitive bank in Sweden, raising issues of the sustainability in terms of competence and competence development. The purpose of this paper is to study how the staff members in a bank perceive a company culture and how this perception…

  10. A micromanipulation cell including a tool changer

    Science.gov (United States)

    Clévy, Cédric; Hubert, Arnaud; Agnus, Joël; Chaillet, Nicolas

    2005-10-01

    This paper deals with the design, fabrication and characterization of a tool changer for micromanipulation cells. This tool changer is part of a manipulation cell including a three linear axes robot and a piezoelectric microgripper. All these parts are designed to perform micromanipulation tasks in confined spaces such as a microfactory or in the chamber of a scanning electron microscope (SEM). The tool changer principle is to fix a pair of tools (i.e. the gripper tips) either on the tips of the microgripper actuator (piezoceramic bulk) or on a tool magazine. The temperature control of a thermal glue enables one to fix or release this pair of tools. Liquefaction and solidification are generated by surface mounted device (SMD) resistances fixed on the surface of the actuator or magazine. Based on this principle, the tool changer can be adapted to other kinds of micromanipulation cells. Hundreds of automatic tool exchanges were performed with a maximum positioning error between two consecutive tool exchanges of 3.2 µm, 2.3 µm and 2.8 µm on the X, Y and Z axes respectively (Z refers to the vertical axis). Finally, temperature measurements achieved under atmospheric pressure and in a vacuum environment and pressure measurements confirm the possibility of using this device in the air as well as in a SEM.

  11. Are You a Man or a Mouse?

    DEFF Research Database (Denmark)

    Herrmann, Janne Rothmar

    2008-01-01

    Are you a man or a mouse? This expression is used to encourage someone to be brave when they are frightened of doing something. It is also an expression which bears associations to John Steinbeck's novella Of Mice and Men, the title of which is taken from Robert Burns' poem To a Mouse, which...

  12. A new way of editing a flora

    NARCIS (Netherlands)

    Burg, van der W.J.; Maesen, van der L.J.G.; Akoègninou, A.; Yédomonhan, H.

    2010-01-01

    Modern electronic tools have become common tools of most scientists. Flora writers and other botanists producing large manuscripts with a certain fixed structure may go even further and use the so-called Mail Merge option in a word processor such as Microsoft Word™. This tool allows structuring a

  13. A case of tripody in a pigeon

    International Nuclear Information System (INIS)

    Luethgen, W.; Krautwald-Junghanns, M.E.

    1994-01-01

    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

  14. Stabilizing a Bicycle: A Modeling Project

    Science.gov (United States)

    Pennings, Timothy J.; Williams, Blair R.

    2010-01-01

    This article is a project that takes students through the process of forming a mathematical model of bicycle dynamics. Beginning with basic ideas from Newtonian mechanics (forces and torques), students use techniques from calculus and differential equations to develop the equations of rotational motion for a bicycle-rider system as it tips from…

  15. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Posture! Is My Child at Risk for Early Childhood Tooth Decay? Men: Looking for a Better Job? Start by Visiting the Dentist Learn what those dental words mean. The Life of a Tooth Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  16. Death ends a life not a relationship

    DEFF Research Database (Denmark)

    Christensen, Dorthe Refslund; Sandvik, Kjetil

    2015-01-01

    When parents are expecting, the child is usually awaited with hope and plans and reflections on how to share the life and future with this new child. As such the child opens the parents' perspective to a new future, a span of time or potentiality, a certain narrative—that is, being parents, raisi...

  17. A View of Newton as a Mathematician

    Indian Academy of Sciences (India)

    GENERAL I ARTICLE. A View of Newton as a Mathematician. A K Nandakumaran. In this article, we present certain topics such as quadrature of planar regions, introduced prior to the invention of calculus by Newton, and con- sider his other mathematical contributions, to bi- nomial theorem and infinite series, cubics, theory.

  18. 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)

  19. 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…

  20. "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…

  1. A Picture is Worth a Thousand Words

    Science.gov (United States)

    Davison, Sarah

    2009-01-01

    Lions, tigers, and bears, oh my! Digital cameras, young inquisitive scientists, give it a try! In this project, students create an open-ended question for investigation, capture and record their observations--data--with digital cameras, and create a digital story to share their findings. The project follows a 5E learning cycle--Engage, Explore,…

  2. 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 ac...

  3. Pellets - A fuel with a future

    International Nuclear Information System (INIS)

    2004-01-01

    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. 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.

  5. 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.”

  6. 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.”

  7. A review of AbobotulinumtoxinA (Dysport).

    Science.gov (United States)

    Lorenc, Z Paul; Kenkel, Jeffrey M; Fagien, Steven; Hirmand, Haideh; Nestor, Mark S; Sclafani, Anthony P; Sykes, Jonathan M; Waldorf, Heidi A

    2013-03-01

    AbobotulinumtoxinA was approved by the US Food and Drug Administration in 2009 as the second botulinum neurotoxin type A (BoNTA) for use in facial aesthetics. This article provides an overview of abobotulinumtoxinA's applications and indications as well as safety and efficacy data. AbobotulinumtoxinA is generally well tolerated. Adverse events from abobotulinumtoxinA are similar to those reported with other BoNTA products. Clinical applications of the product are also discussed in this article. Information on handling, storage, and dosing is provided.

  8. A Wimba Way, A Wimba Way

    OpenAIRE

    Beck, Charlotte; Miller, Katherine; Taylor, Sally

    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”...

  9. 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.

  10. 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.

  11. A quality roadmap of a restructured hospital.

    Science.gov (United States)

    Chow-Chua, C F; Goh, M

    1999-09-01

    This paper presents a quality roadmap of a restructured hospital. Specifically, a case study is showcased to reveal how a FOCUS-PDCA model is applied to the Central Portering Services (CPS) within a restructured hospital, to provide better service to other departments within the hospital who can then in turn value add to the patient care delivery chain. The preliminary results suggest that implementers of quality and service improvement programmes using the FOCUS-PDCA approach should note some of the key implementation difficulties. These difficulties occur at all levels and include issues relevant to change management, process improvement programmes, accessibility to data, communication and judicious execution of the change process.

  12. A game is a game is a game

    DEFF Research Database (Denmark)

    Jørgensen, Ida Kathrine Hammeleff

    2017-01-01

    Recently self-referentiality have occurred as a trend among game designers and have also enjoyed sporadic attention in academia. However, in academia, discussions of self-referential games often rest on proceduralist arguments and a too exclusive focus on the game object. This paper draws...... on the typology of meta-pictures developed by art historian J.W.T. Mitchell. Based on this typology, this paper discusses the notion of meta-games and suggest a broad conception of such games that includes not only the game object, but also the player and the discourse in which it is interpreted....

  13. 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.

  14. 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.

  15. A marketing strategy for a nursing college.

    Science.gov (United States)

    Pryde, M; Muller, M

    1995-08-01

    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.

  16. A marketing strategy for a nursing college

    Directory of Open Access Journals (Sweden)

    M. Pryde

    1995-03-01

    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.

  17. JESUS: A FESTA E A MORTE

    Directory of Open Access Journals (Sweden)

    Jaldemir Vitorio

    1989-01-01

    Full Text Available Encontramos, no evangelho de João, cenas da vida de Jesus onde o evangelista se mostra um mestre na arte de narrar. Jo 5,1-18 é um bom exemplo disto. Uma palavra vivificadora de Jesus põe em movimento uma ação cujo desfecho será a perpetração de sua morte. O pano de fundo da cena é a celebração de uma festa onde a presença de Jesus se torna problemática. A narração é simples. Todavia, uma leitura atenta e detalhada nos mostrará sua articulação interna e as tensões aí presentes.

  18. 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.

  19. When is a theory a theory? A case example.

    Science.gov (United States)

    Alkin, Marvin C

    2017-08-01

    This discussion comments on the approximately 20years history of writings on the prescriptive theory called Empowerment Evaluation. To do so, involves examining how "Empowerment Evaluation Theory" has been defined at various points of time (particularly 1996 and now in 2015). Defining a theory is different from judging the success of a theory. This latter topic has been addressed elsewhere by Michael Scriven, Michael Patton, and Brad Cousins. I am initially guided by the work of Robin Miller (2010) who has written on the issue of how to judge the success of a theory. In doing so, she provided potential standards for judging the adequacy of theories. My task is not judging the adequacy or success of the Empowerment Evaluation prescriptive theory in practice, but determining how well the theory is delineated. That is, to what extent do the writings qualify as a prescriptive theory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. A strain gauge

    DEFF Research Database (Denmark)

    2017-01-01

    The invention relates to a strain gauge of a carrier layer and a meandering measurement grid (101) positioned on the carrier layer, wherein the measurement grid comprises a number of measurement grid sections placed side by side with gaps in between, and a number of end loops (106) interconnecting...... relates to a method for manufacturing a strain gauge as mentioned above....

  1. A section of a pacing mine timbering

    Energy Technology Data Exchange (ETDEWEB)

    Hodous, J.; Kubac, J.; Novak, Z.; Skrobalek, J.; Zajic, K.

    1982-04-15

    A section is proposed for a pacing mine support of the wall and supporting type, designed for reinforcing the operational space of a longwall. The support section differs from the known in that it has relatively large mobility with the use of single stage telescopic hydraulic uprights. The section has left and right skiis, to which the tunneling machine with an upper part is attached using a hinged link. One hydraulic upright is installed on each ski, while a device for advancing the support is installed between the skiis. It is linked using a trough with the longwall conveyor which is not shown in the figure. A complex shaped track is made on each ski with three support recesses located at a different height relative to the base of the ski. The hydraulic upright is linked by its fixed part with the upper part of with the heading machine. The support has controllable projections on two sides, each of which is inserted in a track. Moreover, the support is attached to a hydraulic power cylinder, which is hinged with one of the skiis.

  2. 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

  3. A model for a dia-electric

    International Nuclear Information System (INIS)

    Narnhofer, H.; Thirring, W.

    1989-01-01

    Andre Martin is the master of the Schroedinger equation. Where others may do with cheap approximations he would not buy anything but a conclusive result proved by hard analysis. In recent years he applied his skill to meson spectroscopy where one deals with confining potentials. As a birthday present we will offer him a charged medium which gives such a potential purely in the framework of electrodynamics. We realize that this is just a toy and not the mechanism realized in nature. There it is supposed to emerge from QCD where also nonlinear and quantum effects are important. But our model may provide a formal basis to the heuristic discussions one finds in textbooks [1,2]. 6 refs. (Author)

  4. A Taurus Map on a Minoan Vase?

    Science.gov (United States)

    Banos, G.

    During the excavation of a shrine at Anemospilia on Crete in 1979, richly decorated vase was discovered, like that appearing on the sarcophagus of Aghia Triada to be used for the collection of the blood of the sacrifices bull. The vase was dated to the Middle Minoan period (around 1700 B.C.) The central motif of the decoration of the vase is a plastic bull painted off- white, with a pattern of red round spots scattered over its body. The whole decoration was considered by the excavators and other investigators, as a "speaking symbol" of a bull sacrifice. In this article we suggest that the pattern of round spots could be considered as a map of the Taurus constellation, the oldest one known in the Aegean moreover, that the whole decoration refers to Spring, when the vernal equinox was located in Taurus in Minoan Times. We also suggest that the beginning of the year would be fixed following this equinox.

  5. A system for biasing a differential amplifier

    International Nuclear Information System (INIS)

    Barbier, Daniel; Ittel, J.M.; Poujois, Robert

    1975-01-01

    This invention concerns a system for biasing a differential amplifier. It particularly applies to the integrated differential amplifiers designed with MOS field effect transistors. Variations in the technological parameters may well cause the amplifying transistors to work outside their usual operational area, in other words outside the linear part of the transfer characteristic. To ensure that these transistors function correctly, it is necessary that the value of the voltage difference at the output be equally null. To do this and to centre on the so called 'rest' point of the amplifier transfer charateristic, the condition will be set that the output potentials of each amplifier transistor should have a zero value or a constant value as sum. With this in view, the bias on the source (generally a transistor powered by its grid bias voltage) supplying current to the two amplifying transistors fitted in parallel, is permanently adjusted in a suitable manner [fr

  6. A tunable DNA spring in a nanochannel

    Science.gov (United States)

    Riehn, Robert; Staunton, Rory; Lim, Shuang Fang; Bruinsma, Robijn; Reisner, Walter; Austin, Robert

    2007-03-01

    dsDNA becomes linearized when it is confined to nanofluidic channels with a cross-section of (100 nm)^2 or less, which has made them interesting for genomic DNA analyses. DNA is typically manipulated by means of electric fields. We have found that DNA undergoes a phase transition to a condensed state if an a.c. electric field is applied along the channel direction. The molecule collapses to about 1/4 of it's initial contour length. We will discuss how the effect depends on parameters such as frequency, field strength, channel dimensions, and will discuss the origin of the effect. Interestingly, DNA behaves like an artifical muscle that can be triggered by an a.c. electric field. Since the interaction is expected to hold for any solubilized polyelectrolyte, we speculate that the mechanism may lead to a new class of polymer-based mechanical actuators. These would not suffer from depolarization like piezo transducers.

  7. Starting a business through a franchise

    Directory of Open Access Journals (Sweden)

    Dubravka Mahaček

    2013-12-01

    Full Text Available A business can be launched by establishing a new entity, purchasing an existing entity or through a franc - hise. There are certain prerequisites for starting a business, the most important ones being a quality idea and start-up capital. Potential start-up difficulties are inadequate financing, existing competition as well as the process of building your own market position. By purchasing an existing business some risks may be avoided and the opportunity for gaining profit may arise. Profitable operation is possible only if this business has up-to-date products and no outstanding liabilities. This paper discusses franchising business opportunities and the requisite investments and costs, which will bring success if they are accompanied by franchisee’s efforts. The paper aims to present the main characteristics of a franchise business, the necessary investment and the costs which arise in the process, as well as advantages, disadvantages and experiences with this kind of business

  8. Locating a circle on a sphere

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2003-01-01

    We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of weighted distances between the circle and the facilities is minimized, or such that the maximum weighted distance is minimized. The problem properties are analyzed, and we...... give solution procedures. When the circle to be located is restricted to be a great circle, some simplifications are possible....

  9. A Son's Fears and a Father's Response

    Science.gov (United States)

    Eller, Ian

    2013-01-01

    In the days since the surreal horror of December 14th, the author's children have responded to the tragedy differently. His daughter is a first grader, and she lost many of her friends to the gunman. She has been melancholy, sad in a way only a child who feels but does not understand her feelings can be. His 9-year-old son has been less sad and…

  10. A COMBINATORIAL PROBLEM ON A DIRECTED GRAPH

    Directory of Open Access Journals (Sweden)

    Osvaldo Marrero

    2016-08-01

    Full Text Available We consider two options for a particle’s entire journey through a certaindirectedgraph. Both options involve a random assignment to the journey route to be followed. We are interested in the option that offers, on average, the shortest route. Therefore, we determine the average journey length for each of the two options. As part of our analysis, we provesome combinatorial identities that appear to be new. Some suggestions for further work are given.

  11. 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.

  12. A big measurement of a small moment

    Science.gov (United States)

    E Sauer, B.; Devlin, J. A.; Rabey, I. M.

    2017-07-01

    A beam of ThO molecules has been used to make the most precise measurement of the electron’s electric dipole moment (EDM) to date. In their recent paper, the ACME collaboration set out in detail their experimental and data analysis techniques. In a tour-de-force, they explain the many ways in which their apparatus can produce a signal which mimics the EDM and show how these systematic effects are measured and controlled.

  13. A platform for a smart learning environment

    OpenAIRE

    Simić, Konstantin; Despotović-Zrakić, Marijana; Bojović, Živko; Jovanić, Branislav; Knežević, Đorđe

    2016-01-01

    In this paper, a modular platform which provides student services for smart educational environment is described. The platform represents a point of mutual integration of various services, such as hosting platform for students’ projects, platform for integrating SMS service with students’ web applications, Internet of Things platform which enables acquiring data from sensors distributed within the University building and controlling various actuators. Platform is deployed as a part of Smart L...

  14. CASAS: A Smart Home in a Box.

    Science.gov (United States)

    Cook, Diane J; Crandall, Aaron S; Thomas, Brian L; Krishnan, Narayanan C

    2013-07-01

    While the potential benefits of smart home technology are widely recognized, a lightweight design is needed for the benefits to be realized at a large scale. We introduce the CASAS "smart home in a box", a lightweight smart home design that is easy to install and provides smart home capabilities out of the box with no customization or training. We discuss types of data analysis that have been performed by the CASAS group and can be pursued in the future by using this approach to designing and implementing smart home technologies.

  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 case of a ruptured dermoid cyst

    International Nuclear Information System (INIS)

    Munemoto, Shigeru; Ishiguro, Shuso; Kimura, Akira; Kogure, Yuzaburou; Wakamatsu, Kouichi; Shimizu, Hiroshi; Hayashi, Morimoto

    1988-01-01

    A case of a ruptured dermoid cyst presenting headaches and dizziness as the only symptoms is presented. A 60-year-old woman was admitted to our hospital after complaining of headaches for 5 years and of dizziness for 1 week. The results of physical and neurological examinations were normal. An X-ray of the skull revealed an intracranial calcification in the left frontal region. CT disclosed calcification and a large low-density area in the left parasellar region and the frontal lobe. The mass consisted of two different areas of density. There were multiple, isolated, low-density spots in the left Sylvian fissure and the interpeduncular cistern. No abnormal enhancement was seen by CECT. Angiograms showed an elevation of the A 1 portion of ACA and a lateral shift of MCA. A left fronto-temporal craniotomy was performed. Chronic or past leptomeningitis was suspected because of the arachnoid-membrane thickening. Multiple fatty globules were present in the left Sylvian fissure. A large, soft, fatty tumor was completely removed. The histologic diagnosis was a dermoid cyst. After this operation, the headaches and dizziness were reduced. It is unclear whether the headaches were caused by the compression of the tumor or by the meningeal irritation of the fatty debris. According to the findings on the arachnoid membrane, however, it seems likely that fatty debris detached from the tumor spilled out intermittently from the cyst into the subarachnoid space, resulting in meningeal irritation. (author)

  17. Finding a source inside a sphere

    International Nuclear Information System (INIS)

    Tsitsas, N L; Martin, P A

    2012-01-01

    A sphere excited by an interior point source or a point dipole gives a simplified yet realistic model for studying a variety of applications in medical imaging. We suppose that there is an exterior field (transmission problem) and that the total field on the sphere is known. We give analytical inversion algorithms for determining the interior physical characteristics of the sphere as well as the location, strength and orientation of the source/dipole. We start with static problems (Laplace’s equation) and then proceed to acoustic problems (Helmholtz equation). (paper)

  18. Parkinson's: a syndrome rather than a disease?

    Science.gov (United States)

    Titova, Nataliya; Padmakumar, C; Lewis, Simon J G; Chaudhuri, K Ray

    2017-08-01

    Emerging concepts suggest that a multitude of pathology ranging from misfolding of alpha-synuclein to neuroinflammation, mitochondrial dysfunction, and neurotransmitter driven alteration of brain neuronal networks lead to a syndrome that is commonly known as Parkinson's disease. The complex underlying pathology which may involve degeneration of non-dopaminergic pathways leads to the expression of a range of non-motor symptoms from the prodromal stage of Parkinson's to the palliative stage. Non-motor clinical subtypes, cognitive and non-cognitive, have now been proposed paving the way for possible subtype specific and non-motor treatments, a key unmet need currently. Natural history of these subtypes remains unclear and need to be defined. In addition to in vivo biomarkers which suggest variable involvement of the cholinergic and noradrenergic patterns of the Parkinson syndrome, abnormal alpha-synuclein accumulation have now been demonstrated in the gut, pancreas, heart, salivary glands, and skin suggesting that Parkinson's is a multi-organ disorder. The Parkinson's phenotype is thus not just a dopaminergic motor syndrome, but a dysfunctional multi-neurotransmitter pathway driven central and peripheral nervous system disorder that possibly ought to be considered a syndrome and not a disease.

  19. [A Listeria breast abscess in a man].

    Science.gov (United States)

    Marsaudon, E; Berthy, J; Mamoune, S; Deniel, A; Ksiyer, S; Tiuca, D

    2018-03-01

    Listeriosis is a food-borne illness leading to bacteriemia or central nervous system infection especially in pregnant women or high-risk patients. It is rarely a localized infection. Breast contamination has rarely been reported in lactating women. We report a breast abscess in man. A 80 year old man, hypertensive and arrhythmic, was explored for weakness and dehydration. Type 2 diabetes and chronic lymphocytic leukemia were diagnosed. Clinical examination disclosed a breast abcess related to L monocytogenes infection. Histopathological study also revealed a breast subcutaneous infiltration by chronic lymphocytic leukemia. Listeriosis sometimes uncover an unknown immunosuppression, especially in the elderly. Breast is a non-sterile tissue containing a stable microbiome partly from digestive origin. It can thereby be contaminated by Listeria. The specific cutaneous infiltrate of chronic lymphocytic leukemia can create the conditions for a local infection. Copyright © 2017 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  20. Fighting a family's corner.

    Science.gov (United States)

    2016-12-08

    Why did you become a children's nurse? I was working in retail as a manager with Tesco when I decided to work in healthcare. I qualified as a learning disability nurse before returning to university to complete a paediatric qualification.

  1. A unilateral optic perineuritis in a teenager - A case report.

    Science.gov (United States)

    Ameilia, Ahmad; Shatriah, Ismail; Wan-Hitam, Wan Hazabbah; Yunus, Rohaizan

    2015-06-01

    Optic perineuritis is an uncommon inflammatory disorder that involves optic nerve sheath. Numerous case reports have been published on optic perineuritis in adults, the majority of whom had bilateral presentation. There are limited data on optic perineuritis occurring in pediatric patients. We report a teenager who presented with a unilateral sign that mimicked the presentation of optic neuritis. The orbit and brain magnetic resonance imaging confirmed features of unilateral optic perineuritis. She was treated with a high dose of corticosteroids for 2weeks, and her final visual outcome was satisfactory. No signs of relapse were noted during follow-up visits. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  2. A FOTOGRAFIA ENTRE A ARTE POPULAR E A ARTE ERUDITA

    Directory of Open Access Journals (Sweden)

    Marcos Fabris

    2013-09-01

    Full Text Available Este artigo pretende discutir alguns dos aspectos que marcam o estabelecimento e a dissolução das fronteiras entre dois pólos convencionalmente descritos como arte culta e arte popular, tecendo paralelos entre o teatro de variedades, forma de expressão popular por excelência, e a fotografia, expressão artística que desde seus primórdios circula entre os dois extremos deste contínuo. Nestes termos, ambiciona-se verificar como determinadas condições sócio-históricas favorecem a criação de recursos formais que minimizam, ou suprimem, tais distinções consagradas pela crítica de arte.

  3. 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.

  4. A NEW DIVIDE: A ROMANTIC VERSUS A CLASSICAL ORTHODOXY

    Directory of Open Access Journals (Sweden)

    J. MILBANK

    2011-08-01

    Full Text Available In his contribution, the author wishes to trace a few of the contemporary trends of western European theology. He notes that alongside the growing infl uence of Roman Catholic theological thought in the West, there also arose a new theological divide between, what he terms, the romantic and the classical modes of theological orthodoxy. Both positions use diff erent methodological approaches in their common attempt at off ering resistance to secular modernity: the former appealing to the senses, the imagination and the fantasy, and the latter to unadulterated human reason.

  5. A Powerful Public Sphere?

    DEFF Research Database (Denmark)

    Fiig, Christina

    The paper holds a critical discussion of the Habermasian model of the public sphere and proposes a revised model of a general public......The paper holds a critical discussion of the Habermasian model of the public sphere and proposes a revised model of a general public...

  6. A tribute to James A. Holcombe

    Science.gov (United States)

    Sturgeon, Ralph

    2015-03-01

    My first interaction with Jim Holcombe was by letter in late 1977 (well before our instant e-mail communications age we all enjoy and/or curse). Jim was enquiring via some subtle questions about a paper I had recently published in Analytical Chemistry on the mechanisms of atomization in the graphite furnace. This brief correspondence initiated a 35 year period of technical interaction and friendship which literally carried us throughout the world to many conferences and more than a few shared hotel rooms in the days when one would make sacrifices to reduce travel costs to enable conference attendance. At the SciX 2013 (FACSS) meeting in Milwaukee WI, a special symposium was organized by John Molloy in honor of Jim's achievements. This was the closest "public" venue to correspond with Jim's announced 2013 spring retirement and his "exit" from a working career at the Department of Chemistry, University of Texas at Austin. It was a distinct honor for me to have Nicolo Omenetto ask if I would help coordinate this special issue of Spectrochim. Acta, Part B in honor of Jim's career/achievements. This gives me the opportunity to publicly comment on my personal association with this "Texas" gentleman from Colorado, a genuine "out of the box" thinker, a productive, highly acknowledged but humble character that I am grateful to have known, and with whom I have traveled the world and enjoyed so many good times.

  7. DAIRY PRODUCTION: A NUTRITION INTERVENTION IN A ...

    African Journals Online (AJOL)

    A study to assess the impact of dairy production on the nutritional status of preschool children aged between 24 and 59 months in Mumias Division, a predominantly sugarcane growing zone of Western Kenya was undertaken between 1997 and 1998. Nutritional status was assessed by taking height, weight and age of the ...

  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. Professor Hans A Bethe - A Brief Homage

    Indian Academy of Sciences (India)

    physics. In fact his earliest major work, based on his doctoral studies with Sommerfeld, was actually in solid state physics, resulting in a seminal survey of the electronic theory of metals published in 1933 in the Handbuch der Physik. Bethe also had a major role to play in the creation of nuclear weapons as the Head of.

  10. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Children's Oral Health What is a Composite Resin (White Filling)? The ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  11. A Haldane perspective from a Fisher student

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 96; Issue 5. A Haldane perspective from a Fisher student. W. F. BODMER. HALDANE AT 125 Volume 96 Issue 5 November 2017 pp 743-746. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/jgen/096/05/0743-0746. Keywords.

  12. 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.

  13. 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...

  14. When a body meets a body

    DEFF Research Database (Denmark)

    Pelowski, Matthew John; Liu, Tao; Palacios, Victor

    2014-01-01

    We consider the phenomenon of social interactions within the art museum, arguing that even the bare possibility of meeting others or intruding into their gaze can have a profoundly detrimental effect on art experience. This is done by tracing a finding from our previous studies in which we consid...

  15. Nasopharyngeal Hemangiopericytoma in a Sudanese child: A ...

    African Journals Online (AJOL)

    These cells can be found surrounding all capillaries and are thought to be immature smooth muscle derived from mesenchyme. Pericytes add structural support to the capillaries and have a contractile capability playing a role in capillary blood flow regulation, modulating both flux and permeability1,3,4. Approximately 1% of ...

  16. A Haldane perspective from a Fisher student

    Indian Academy of Sciences (India)

    W. F. Bodmer

    2017-11-24

    Nov 24, 2017 ... Keywords. blood groups; human genetics; population genetics; natural and artificial selection. Introduction. J. B. S. Haldane, with ... Council committee on Human Genetics, of which Fisher was a member and Haldane its .... genes making for certain kinds of altruistic behaviour'. This suggestion, and a similar ...

  17. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Bomberman atari oyunlarý bakugan oyunlarý geta poker friv Home InfoBites Find an AGD Dentist Your Family's Oral ... dental words mean. The Life of a Tooth Home | InfoBites | Find a Dentist | Your Family's Oral Health | ...

  18. Urihi A: A Terra-Floresta Yanomami

    Directory of Open Access Journals (Sweden)

    James R. Welch

    2010-08-01

    Full Text Available 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.

  19. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... InfoBites Quick Reference Learn more Pregnancy and Oral Health Men: Looking for a Better Job? Start by ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  20. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... InfoBites Quick Reference Learn more Pregnancy and Oral Health Men: Looking for a Better Job? Start by Visiting the Dentist When Should My Child First See a Dentist? Pacifiers Have Negative and Positive Effects Are You Biting Off More Than You Can ...

  1. A Transmedia Topology of 'Making a Murderer'

    NARCIS (Netherlands)

    Hook, Alan; Barrios-O'Neill, Danielle; Mairs Dyer, Jolene

    2016-01-01

    textabstractThis article constructs a transmedia topology of the Making a Murderer text, demonstrating influences of various forms of documentary, interactive gaming culture, and post-digital writing on the series itself as well as on the paratextual cloud of works that grew up around it. Here we

  2. Designing for a Dollar a Day

    DEFF Research Database (Denmark)

    Kyng, Morten

    1988-01-01

    for independent end user design activities. I go on by presenting a set of "cheap tools" and techniques, including the use mockup's. This set covers the issues of establishing the possibility of alternatives, of creating visions of new and different uses of technology, and of designing computer support. A central...

  3. 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.

  4. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Posture! Learn what those dental words mean. The Life of a Tooth Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints and Permissions | Privacy Statement | Terms and Conditions © 1996-2018 Academy of General Dentistry. All Rights Reserved.

  5. Becoming a Writer: A Documentary Account.

    Science.gov (United States)

    Himley, Margaret

    1988-01-01

    Documents a seven-year-old child's early activities as a writer from the perspective of (1) intentionality, (2) conditions and production, (3) learning strategies, (4) composing patterns in other semiotic activities, (5) availability, and (6) literacy community, and attempts to analyze those activities through narrative, explication and argument.…

  6. 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,…

  7. 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. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. 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…

  9. A step up for a few postdocs

    CERN Document Server

    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).

  10. National Service: A Responsibility, A Solution

    Science.gov (United States)

    1991-04-12

    their actions. In contrast, today’s youth have been characterized by some as apathetic, apolitical, and materialistic . Others say that this is a...or older, volunteered, including 52% teenagers . Pollster, Louis Harris, corroborates the Gallup findings in a 1985 survey, concluding that the "youth

  11. 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…

  12. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... friv Home InfoBites Find an AGD Dentist Your Family's Oral Health About the AGD Dental care and ... a Tooth Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site ...

  13. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... friv Home InfoBites Find an AGD Dentist Your Family's Oral Health About the AGD Dental care and ... a Tooth Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | ...

  14. 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 i...

  15. PLANT PATHOLOGY: a discipline at a crossroads.

    Science.gov (United States)

    Weinhold, A R

    1996-01-01

    The Department of Plant Pathology at the University of California at Berkeley was destroyed as a consequence of a contentious reorganization. The circumstances that led to the reorganization provide some insight into the challenges facing the discipline of plant pathology. The underlying basis for plant pathology as a science is to address problems of plant disease. This requires a balance between disciplinary and problem-solving research and a continuum from achieving fundamental advances in knowledge to the development and implementation of problem-solving approaches. Changes in colleges and universities have placed extreme stress on this essential structure. The dilemma that must be addressed is how to reestablish the problem-solving continuum where it has been broken and strengthen it where it has been weakened. Plants are essential for life, and they will always be affected by disease. The understanding and management of these diseases is the responsibility and the challenge of plant pathology today and in the future.

  16. 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.; hide

    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.

  17. From a magnet to a heat pump

    DEFF Research Database (Denmark)

    Navickaité, Kristina; Neves Bez, Henrique; Engelbrecht, Kurt

    2016-01-01

    The magnetocaloric effect (MCE) is the thermal response of a magnetic material to an applied magnetic field. Magnetic cooling is a promising alternative to conventional vapor compression technology in near room temperature applications and has experienced significant developments over the last five...... years. Although further improvements are necessary before the technology can be commercialized. Researchers were mainly focused on the development of materials and optimization of a flow system in order to increase the efficiency of magnetic heat pumps. The project, presented in this paper, is devoted...... to the improvement of heat pump and cooling technologies through simple tests of prospective regenerator designs. A brief literature review and expected results are presented in the paper. It is mainly focused on MCE technologies and provides a brief introduction to the magnetic cooling as an alternative...

  18. 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

  19. A design for a reusable Ada library

    Science.gov (United States)

    Litke, John D.

    1986-01-01

    A goal of the Ada language standardization effort is to promote reuse of software, implying the existence of substantial software libraries and the storage/retrieval mechanisms to support them. A searching/cataloging mechanism is proposed that permits full or partial distribution of the database, adapts to a variety of searching mechanisms, permits a changine taxonomy with minimal disruption, and minimizes the requirement of specialized cataloger/indexer skills. The important observation is that key words serve not only as indexing mechanism, but also as an identification mechanism, especially via concatenation and as support for a searching mechanism. By deliberately separating these multiple uses, the modifiability and ease of growth that current libraries require, is achieved.

  20. A multiplicity trigger for a Cherenkov detector

    International Nuclear Information System (INIS)

    Jonsson, P.

    1984-05-01

    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. 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; 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; Wiegand, B; Weigand, B; Wiersema, K; Yatsu, Y; Yoshii, T; Tagliaferri, G

    2014-01-03

    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 ~ 3 × 10(53) ergs per second) and its relative proximity (z = 0.34), GRB 130427A reached the highest fluence observed in the γ-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.

  2. Workplace spirituality: A tool or a trend?

    Directory of Open Access Journals (Sweden)

    Philip J.W. Schutte

    2016-08-01

    Full Text Available Workplace spirituality is a construct widely discussed over the past few decades and it is a much-disputed inquiry field which is gaining the interest of practitioners and scholars. Some clarifications regarding concepts and definitions are necessary in order to structure and direct the current debate. The aim of this conceptual article is to gain a better understanding regarding the direction in which this field of study is progressing and to put the question on the table namely, whether workplace spirituality is only a new tool to be used in leadership development or is it a trend to be taken seriously? The results showed that this field has potential to further development. This article can be used as foundation for future studies within the knowledge area of practical theology.

  3. A sun holiday is a sunburn holiday

    DEFF Research Database (Denmark)

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

    2013-01-01

    Many people take holidays in sunny locations with the express aim of sunbathing. This may result in sunburn, which is a risk factor for skin cancer. We investigated 25 Danish sun seekers during a week's holiday in the Canary Islands. The percentage of body surface area with sunburn was determined......-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 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...

  4. Controlling a nuclear spin in a nanodiamond

    Science.gov (United States)

    Knowles, Helena S.; Kara, Dhiren M.; Atatüre, Mete

    2017-09-01

    The sensing capability of a single optically bright electronic spin in diamond can be enhanced by making use of proximal dark nuclei as ancillary spins. Such systems, so far realized only in bulk diamond, can provide orders of magnitude higher sensitivity and spectral resolution in the case of magnetic sensing, as well as improved readout fidelity and state storage time in quantum information schemes. Nanodiamonds offer opportunities for scanning and embedded nanoscale probes, yet electronic-nuclear spin complexes have so far remained inaccessible. Here, we demonstrate coherent control of a 13C nuclear spin located 4 Å from a nitrogen-vacancy center in a nanodiamond and show coherent exchange between the two components of this hybrid spin system. We extract a free precession time T2* of 26 μ s for the nuclear spin, which exceeds the bare-electron free-precession time in nanodiamond by two orders of magnitude.

  5. A Hop, Skip and a Jump Away

    DEFF Research Database (Denmark)

    Smith, Shelley

    2009-01-01

    that focuses on clearly demarcated borders for containment. The discipline of parkour - the art of movement - will be used as a lens through which to view the potential that lies in activating the indeterminate city, and accessing a sense of ownership, belonging and interconnectivity in urban public space.......This paper will address spatial experience and issues of ownership, exchange and indeterminateness in urban public space. The contemporary urban situation is characterised by media and mobility, where the potential for alienation - not only from each other, but also from the spaces we occupy......, is prevalent. Themed and ‘designed' spaces - many of the most common public spaces of the contemporary urban environment - often propagate a limitation in the diversity of their users, but they also propagate a kind of spatial inertia - an object-fixation prescribing use within a pre-determined schematic...

  6. Gingivectomía a bisel externo

    Directory of Open Access Journals (Sweden)

    Teresita Burgos Fuentes

    2014-06-01

    Full Text Available ResumenEl propósito de este reporte es describir el alargamiento coronario como tratamiento estético periodontal. La gingivectomía es un tratamiento quirúrgico antiguo. La indicación para la gingivectomía es la eliminación completa de la bolsa periodontal, hiperplasias. El diseño fisiológico del margen libre gingival por el medio quirúrgico debe ser tomado en consideración. Se reporta un caso clínico de un paciente masculino de 32 años de edad que exhibe gran cantidad de encía cuando sonríe. El logro de resultados estéticos excelentes en la terapia no es una cuestión de azar, es algo planificado antes de iniciar el tratamiento. (Duazary 2008; 125-128AbstractThe purpose of this report is to describe the external level gingivectomy as a periodontal esthetic treatment; the gingivectomy is the oldest surgical approach in periodontal therapy. Indication for performance of the gingivectomy is the complete elimination of the periodontal pocket and hyperplasia gingival. The physiologic design of the free gingival margin by surgical means, gingivoplasty, must be taken under consideration. A clinic case is been reported, a 32 years old with a big amount of gum tissue when she smiles. The achievement of excellent esthetics results on a therapy is not a matter of luck, must be into the treatment plan before starting this one.Key words: periodontal treatment; gingivectomy; gingival hyperplasia.

  7. A box of mirrors, a unicorn, and a pony

    Directory of Open Access Journals (Sweden)

    Jules Wilkinson

    2010-03-01

    Full Text Available Fans and creators have traditionally treated fanworks with a "don't ask, don't tell" policy. However, Supernatural incorporates fans and their creative works into the show itself, changing the status quo of the fan/creator relationship.

  8. A Department Chair: A Life Guard without a Life Jacket

    Science.gov (United States)

    Gonaim, Faiza

    2016-01-01

    Leadership in higher education is fundamental for institutional development and sustainability in today's rapidly changing world. The academic department is a fundamental unit for transforming the university's visions and goals into reality. The vigorous contribution of each department, which depends in turn largely on the effectiveness of the…

  9. A Tribute to a Former Latchkey Kid: Doing a Wheel.

    Science.gov (United States)

    Turgeon, Richard

    1988-01-01

    As an aid to therapists who work with inmates with long or life sentences who are mandated to receive treatment, this article attempts to follow an inmate with a life sentence who passed through stages of fear and anger and began to understand that changes were needed if he were ever to have his sentence commuted. (Author/NB)

  10. 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...

  11. Zassenhaus conjecture for A6 A6 A6

    Indian Academy of Sciences (India)

    Dedicated to the memory of I. S. Luthar†. MS received 10 March 2007. Abstract. For the alternating group A6 of degree 6, Zassenhaus' conjecture about ... either proven or not, and if not, at least some information about partial augmentations is obtained (see [3–6]). †Professor Luthar died at the age of 74 in December 2006.

  12. A nation's voices in a catechism of a 1864 exile

    OpenAIRE

    Grzegorz Ryś

    1994-01-01

    The archives documenting the life of Poles in Siberia, located in the Tobol'sk branch of the Tyumen Oblast National Archive, are to this day completely unexplored by Polish historians. A hand-copied catechism, associated with the person known as KK, is an undisputed gem in this collection of documents.

  13. A NEW CONTRACT ON EDUCATION? - A HISTORY OF A PROCESS

    Directory of Open Access Journals (Sweden)

    Manuel de Puelles Benítez

    2010-05-01

    After locating the contract on education in its historical and political background, this article reveals its meaning throughout time since the 1978 Spanish Constitution came in force, while, at the same time, it takes a practical outlook on the reasons why it is necessary and why it recently failed to be.

  14. 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

  15. 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

  16. Hyponatremia in a Teenager: A Rare Diagnosis.

    Science.gov (United States)

    Correia, Filipa; Fernandes, Alexandre; Mota, Teresa C; Garcia, Milagros; Castro-Correia, Cíntia; Fontoura, Manuel; Ribeiro, Augusto

    2015-12-01

    Hyponatremia is a common electrolyte alteration which has the potential for significant morbidity and mortality. Endocrine disorders, such as primary hypothyroidism and adrenal insufficiency are uncommon causes of hyponatremia. We present the case of a teenager with symptomatic hyponatremia caused by a rare disorder. A 17-year-old boy was admitted to the emergency department with abdominal pain, nausea and vomiting, asthenia, and weight loss. He was in poor general condition, hypotensive, and he had dry mucous membranes and skin as well as mucosa hyperpigmentation. The laboratory findings showed severe hyponatremia, hyperkalemia, and renal dysfunction. The patient started inotropic support and antibiotics. Plasma cortisol and corticotropin levels allowed the diagnosis of primary adrenal insufficiency. He began replacement therapy with hydrocortisone and fludrocortisone, with gradual symptom resolution. An abdominal computed tomography scan showed adrenal hypoplasia. Findings for antiadrenal and antithyroid antibodies were positive, allowing the diagnosis of autoimmune polyglandular syndrome type II. Adrenal insufficiency is a rare disease, especially in children, and its clinical manifestations are due to glucocorticoid and mineralocorticoid deficiency. In most of the cases, symptoms are nonspecific, requiring a high index of clinical suspicion. If the diagnosis and treatment are delayed, acute adrenal insufficiency carries a high morbidity and mortality.

  17. Bladder necrosis: 'A man without a bladder'.

    Science.gov (United States)

    Bosschieter, Judith; Oudshoorn, Frederik H K; Meuleman, Eric J H; Nieuwenhuijzen, Jakko A

    2018-02-17

    Since the use of antibiotics, bladder necrosis has become a rare condition. We report a case of bladder necrosis in a 90-year-old man following urinary retention. After insertion of a transurethral catheter (TUC), 2 L of urine was evacuated. In the following days, the TUC became intermittently blocked. Adequate bladder drainage could not be obtained despite intensive rinsing and placement of a suprapubic catheter. On surgical exploration necrosis of almost the entire bladder wall, except for the trigone, was encountered. Surgical debridement of the non-viable bladder wall without opening the abdominal cavity was conducted, and a TUC was placed in the Retzius cavity to ensure evacuation of urine. Since the patient was haemodynamically unstable, construction of a urinary diversion was waived and urinary drainage of the Retzius cavity by the TUC was accepted, resulting in adequate urinary drainage without compromising renal function. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. 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...

  19. Finding a Forest in a Tree

    DEFF Research Database (Denmark)

    Bacci, Giorgio; Miculan, Marino; Rizzi, Romeo

    2014-01-01

    Wide reactive systems are rewriting systems specified by wide reaction rules, where redex and reactum are lists of terms (forests), i.e. rules of the form ⟨l1(x1),…,ln(xn)⟩⇒⟨r1(y1),…,rn(yn)⟩ such that ∪iyi⊆∪ixi. Wide reaction rules are particularly useful for process calculi for mobile and global...... computations, because they allow one to connect processes which can be at different places in the system, possibly crossing boundaries and firewalls. For instances, remote procedure calls can be modeled as a process in place i activating a reaction in a different place j; code mobility can be modeled...... by instantiating variables in yi with terms using variables from xj, for a different j; etc. In order to apply a wide reaction rule, we have to find a matching of the rule redex within the global state. This problem can be restated as follows: how to match a given forest (the redex) inside an unordered tree (the...

  20. A Transmedia Topology of 'Making a Murderer'

    Directory of Open Access Journals (Sweden)

    Alan Hook

    2016-12-01

    Full Text Available This article constructs a transmedia topology of the Making a Murderer text, demonstrating influences of various forms of documentary, interactive gaming culture, and post-digital writing on the series itself as well as on the paratextual cloud of works that grew up around it. Here we define transmedia topology as a tracing of what we could call the geography of the text, as defined by its features and boundaries (or lack thereof. We will discuss the intentionality of the series creators, as well as the emergence of a transmedial textuality that is owed largely to audiences and the textual terrain. The Making a Murderer series thus becomes the basis for a larger transmedia narrative that sprawls across social-digital networks, a pastiche of multifarious public reaction and unsanctioned investigation.The article maps the ecologies of interaction, participation and creation with and of the text by the audience to map the thresholds of the transmedial text and investigate new approaches to analysing transmedial work in the context of non-fiction media forms.

  1. Ventana a la Farmacología

    Directory of Open Access Journals (Sweden)

    María Luisa Cárdenas Muñoz

    1996-04-01

    Full Text Available Terfenadina: no debe usarse con eritromicina: La terfenadina es un antihistamínico de segunda generación, cuyo uso se ha generalizado por producir menos sedación que los antihistamínicos de primera generación.  / Uso y abuso de corticoides tópicos oculares: A finales de la década de los cuarenta Kench y Kendall introdujeron la cortisona en la terapéutica humana, simultáneamente comenzó a ser utilizada con éxito en las inflamaciones oculares. /  Trastornos de pánico: pato fisiología y tratamiento: El tratamiento farmacológico del pánico se conoce y utiliza desde los años sesenta. Sinembargo, la comprensión del origen biológico de su pato fisiología sólo se comenzó a entender en años recientes. / Acido Acetil Salicilico y riesgo de Cancer Colorecal en mujeres: Evidencias muy importantes sugieren que el uso regular de ácido acetil salicílico (ASA y otros antiinflamatorios no esteroideos (AINE disminuye el riesgo de cáncer colorectal.

  2. 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.

  3. SUPERCOLLIDER: A GEM of a detector

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Now being prepared as a major experimental facility for the 87- kilometre Superconducting Supercollider (SSC) being built in Ellis County, Texas, is the GEM detector project. GEM thus becomes the companion to the Solenoidal Detector Collaboration (SDC), the first major SSC detector to emerge (March 1992, page 13). This is in keeping with the SSC Laboratory's aim of two major detectors with overlapping and complementary strengths. GEM is designed to observe all SSC signatures, with emphasis on precise measurement of electrons, photons and muons. Hence the name GEM - ''Gammas, Electrons and Muons.'' Design goals are clean signatures for leptons, jets, and missing transverse energy, maximum sensitivity to narrow resonances, and low backgrounds. Also important is maintaining significant capability at high luminosity (10 34 cm -2 s -1 ). GEM has some distinctive features. A key concept is the exterior magnet, surrounding all detector elements. Inside the magnet are a muon tracking system, a precision calorimeter, and a compact central tracker. This allows the muon momentum to be measured the air of the radiation shielded area outside the thick calorimeter, giving both high precision and robustness at high luminosity. A large magnet gives a large lever arm (at least 4 m) for precise muon momentum measurement. Placing the magnet outside also minimizes the material between tracker and calorimeters, so that the calorimeters are limited only by their inherent resolutions

  4. Transforming a small business: A learning intervention

    Directory of Open Access Journals (Sweden)

    Dirk J. Geldenhuys

    2012-03-01

    Motivation for the study: This study explored the important role of small businesses; the role of management; and, more specifically, organisation development models that were developed for large corporations; as these emphasise the need to study the purpose of organisation development interventions in small businesses. Research design, approach and method: The study reported on in this article was a qualitative case study in a small brokers company with 21 staff members. The data were analysed manually by means of qualitative content analysis. Main findings: The main finding of the research concerned how experiential learning intervention provided a space for participants to start exploring, and gradually changing the dynamics of their small business, by transforming their business into a more formal company. Practical/managerial implications: The primary implication is that experiential learning interventions that are operationalised, from a psychodynamic perspective, can be valuable when consulted by small businesses during their transformation towards becoming more formal companies. Contribution/value-add: This article contributes to the OD literature on small businesses, with fewer than 50 employees, by providing data on how the learning process, that commenced during an experiential learning intervention, assisted a small company to develop its identity towards that of a more formal company.

  5. 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.

  6. Dial-a-Ride

    DEFF Research Database (Denmark)

    Jørgensen, Rene Munk

    2003-01-01

    . In a Dial-a-Ride transportation system, passengers request a trip between two stops with either a desired time of departure from the pickup stop or a desired time of arrival at the destination. The time windows at the stops are then calculated by the operator based on additional parameters such as maximum......The Dial-a-Ride problem is a Vehicle Routing problem in its most general form. The problem was formulated in the beginning of the 1970's and since then a large number of researchers have worked on developing efficient algorithms for use in automated planning of Dial-a-Ride transportation systems...... is then an extension of the Capacitated Vehicle Routing Problem with Time Windows (CVRPTW) with the additional constraints that a pickup stop must precede a delivery stop for a passenger, and that both a pickup stop and a delivery stop related to the same passenger must be assigned to the same vehicle. The objective...

  7. A vibration sieve

    Energy Technology Data Exchange (ETDEWEB)

    Alekhin, S.A.; Denisenko, V.V.; Dzhalalov, M.G.; Kirichek, F.P.; Pitatel, Yu.A.; Prokopov, L.I.; Tikhonov, Yu.P.

    1982-01-01

    A vibration sieve is proposed which includes a vibration drive, a body and a screen installed on shock absorbers, a device for washing out the screen, and a subassembly for loading the material. To increase the operational reliability and effectiveness of the vibration sieve by improving the cleaning of the screen, the loading subassembly is equipped with a baffle with a lever which is hinged to it. The device for washing out the screen is made in the form of an electromagnet with a connecting rod, a switch and an eccentric, a friction ratchet mechanism and sprinkling systems. Here, the latter are interconnected, using a connecting rod, while the sprinkling system is installed on rollers under the screen. The electromagnetic switch is installed under the lever. The body is made with grooves for installing the sprinkling system. The vibration sieve is equipped with a switch which interacts with the connecting rod. The friction ratchet mechanism is equipped with a lug.

  8. A surprising palmar nevus: A case report

    Directory of Open Access Journals (Sweden)

    Rana Rafiei

    2018-02-01

    Full Text Available Raised palmar or plantar nevus especially in white people is an unusual feature. We present an uncommon palmar compound nevus in a 26-year-old woman with a large diameter (6 mm which had a collaret-shaped margin. In histopathologic evaluation intralymphatic protrusions of nevic nests were noted. This case was surprising to us for these reasons: size, shape, location and histopathology of the lesion. Palmar nevi are usually junctional (flat and below 3 mm diameter and intra lymphatic protrusion or invasion in nevi is an extremely rare phenomenon.

  9. 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...... procedures. When the circle to be located is restricted to be a great circle, some simplifications are possible. The models may be used in preliminary studies on the location of large linear facilities on the earth's surface, such as superhighways, pipelines, and transmission lines, or in totally different...

  10. A School Day is a School Day

    DEFF Research Database (Denmark)

    Engelhardt, Robin

    2007-01-01

    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......: 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...

  11. 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 Translator The 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.

  12. A Treatable Refractory Epilepsy: A Case Report

    Directory of Open Access Journals (Sweden)

    Javad Akhondian

    2014-01-01

    Full Text Available Introduction Biotinidase deficiency is a life threatening inborn error of metabolism specially when delayed in diagnosis. We report a 2-month-old male infant that presented with refractory infantile spasm, alopecia and seborrheic dermatitis. With a high suspicion of the biotinidase deficiency we started biotin 10 mg daily orally before definite diagnosis was made. Rapid treatment was life-saving and all complications disappeared rapidly. With this report we tried to explain the clinical manifestations of biotinidase deficiency and show the importance of early diagnosis and treatment in resolving the complications.  

  13. A case report of a pulmonary abscess

    Directory of Open Access Journals (Sweden)

    Tatiana Fonseca

    2017-03-01

    We describe a case of a 34 year-old, male, with history of lung adenocarcinoma and distal esophagus adenocarcinoma. Was surgically proposed to eso-gastrectomy and eso-gastrostomy. Due the partial dehiscence of the anastomosis, it was placed an endoluminal prosthesis. Three weeks later, it was found an esophageal orifice and a pulmonary abscess due carbapenem resistant klebsiella pneumoniae. He was started on tigecycline, colistine and amphotericin B. However, there wasn’t any improvement, and the patient died on 45th day of his admission. Discussion: Timely microbiological diagnosis, the use of new and old antibiotics and cirurgical intervention appeared to be valuable in managing of this patients.

  14. Cosmic strings: A problem or a solution?

    International Nuclear Information System (INIS)

    Bennett, D.P.; Bouchet, F.R.

    1987-10-01

    The most fundamental issue in the theory of cosmic strings is addressed by means of Numerical Simulations: the existence of a scaling solution. The resolution of this question will determine whether cosmic strings can form the basis of an attractive theory of galaxy formation or prove to be a cosmological disaster like magnetic monopoles or domain walls. After a brief discussion of our numerical technique, results are presented which, though still preliminary, offer the best support to date of this scaling hypothesis. 6 refs., 2 figs

  15. Ventana a la Farmacología

    OpenAIRE

    María Luisa Cárdenas Muñoz; Hernán Pérez; Ramiro Prada Reyes

    1996-01-01

    Terfenadina: no debe usarse con eritromicina: La terfenadina es un antihistamínico de segunda generación, cuyo uso se ha generalizado por producir menos sedación que los antihistamínicos de primera generación.  / Uso y abuso de corticoides tópicos oculares: A finales de la década de los cuarenta Kench y Kendall introdujeron la cortisona en la terapéutica humana, simultáneamente comenzó a ser utilizada con éxito en las inflamaciones oculares. /  Trastornos de pánico: pato fisiología y tratamie...

  16. Education of a college president: a memoir

    International Nuclear Information System (INIS)

    Killian, J.R. Jr.

    1985-01-01

    The reviewer finds Killian's book, The Education of a College President: A Memoir, to be an interesting counterpoint to Kamen's memoir of the political side of the nuclear age. Killian describes his World War II experiences at the Massachusetts Institute of Technology, where a concentration of research scientists worked in harmony in contrast to the situation in California. Killian focuses on the institutional side of cooperation between the university, industry, and the military. The reviewer, who faults Kamen for his claustrophobic approach, expresses disappointment with Killian's impersonal approach

  17. 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.

  18. 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

  19. 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.

  20. The information a history, a theory, a flood

    CERN Document Server

    Gleick, James

    2011-01-01

    Winner of the Royal Society Winton Prize for Science Books 2012, the world's leading prize for popular science writing. We live in the information age. But every era of history has had its own information revolution: the invention of writing, the composition of dictionaries, the creation of the charts that made navigation possible, the discovery of the electronic signal, the cracking of the genetic code. In 'The Information' James Gleick tells the story of how human beings use, transmit and keep what they know. From African talking drums to Wikipedia, from Morse code to the 'bit', it is a fascinating account of the modern age's defining idea and a brilliant exploration of how information has revolutionised our lives.

  1. A new year, a new Journal.

    Science.gov (United States)

    Fokkens, W J

    2018-03-03

    Let us start this first editorial of 2018 with wishing you all a marvelous year where most of your dreams come true. In the last years, the editors of Rhinology felt often very unhappy when again we had to refuse papers send to us for Rhinology. Unfortunately, every year we can only accept around 15% of the papers we receive. With pain in our hearts, we often have to refuse papers of good quality but just not innovative enough or with slight methodological imperfections. The editorial board of Rhinology recognized this feeling and we decided to start a new journal: Rhinology Online to have space for all those papers that are good but just do not make the cut for Rhinology. Rhinology Online is a journal of the European Rhinologic Society, and will provide a platform for the dissemination of rhinologic research and reviews, as well as position papers, task force reports and guidelines, amongst an international scientific audience.

  2. A Fixed Point, A Point of Interruption

    Directory of Open Access Journals (Sweden)

    Mark Hewson

    2006-10-01

    Full Text Available A review of Alain Badiou, emInfinite Thought: Truth and the Return to Philosophy/em, ed. and trans. Justin Clemens and Oliver Feltham, New Edition, London, Continuum, 2005. ISBN: 0826479294.br /

  3. When Is a Program Like a Function?

    Science.gov (United States)

    Klotz, Frederic S.

    1986-01-01

    Functional programming, in which the connection to mathematics is simple and direct, is described. A language such as Logo illustrates the relationship between functional programming and mathematics in more detail. (MNS)

  4. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... InfoBites Quick Reference Learn more Children's Oral Health What is Baby Bottle Tooth Decay? Why is Oral ... Tooth Decay? The History of Dental Advances Learn what those dental words mean. The Life of a ...

  5. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Children's Oral Health Men: Looking for a Better Job? Start by Visiting the Dentist Why is Oral Health Important for Men? Are You Biting Off More ...

  6. A spacetime cloak, or a history editor

    Science.gov (United States)

    McCall, Martin W.; Favaro, Alberto; Kinsler, Paul; Boardman, Allan

    2011-02-01

    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.

  7. A Subdermal Osteochondroma in a Young Girl

    Directory of Open Access Journals (Sweden)

    Heather A. Cole

    2017-01-01

    Full Text Available Osteochondromas are common benign tumors of cartilage and bone. They are usually found as contiguous bone with a cartilage cap at the end of the growth plate of long bones. Similar to structure are extraskeletal osteochondromas. However, unlike typical osteochondromas, extraskeletal osteochondromas are noncontinuous with bone. To our knowledge, all reported extraskeletal osteochondromas have been contained within fascial compartments. Here we present the case of a 5-year-old female who had a slow growing mass of the anterior distal right thigh. Imaging studies revealed an ossified mass extending from dermal layer of the subcutaneous tissue with no connection to the underlying deep fascia. An excisional biopsy was performed and proved to be a subdermal extraskeletal osteochondroma.

  8. Umbanda: entre a cruz e a encruzilhada

    Directory of Open Access Journals (Sweden)

    LÍSIAS NOGUEIRA NEGRÃO

    1993-12-01

    Full Text Available O artigo considera a umbanda, religião afro-brasileira de constituição recente, como estando dividida entre os apelos de suas raízes negras e os atrativos legitimadores da adoção dos princípios éticos cristãos. Embora pouco racionalizada e postulando uma visão de mundo predominantemente encantada, vem crescentemente moralizando-se a partir, sobretudo, das influências do ideal kardecista da caridade. Tal incorporação não é, contudo, linear, mas reinterpretada a partir da vivência concreta de seus agentes e moderada pela necessidade da cobrança por serviços religiosos prestados e pela "demanda", concepção mágica de conflito inter-individual.

  9. A spacetime cloak, or a history editor

    International Nuclear Information System (INIS)

    McCall, Martin W; Favaro, Alberto; Kinsler, Paul; Boardman, Allan

    2011-01-01

    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

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

    Science.gov (United States)

    ... did a tremendous job of giving me the illusion of cleavage with the type of incision she ... Talking With Your Doctor About Breast Surgery Options Self-Image and Cancer More Information: American Cancer Society: ...

  11. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... March 16, 2018 About | Contact InfoBites Quick Reference Learn more Pregnancy and Oral Health What is Dental ... Dentist? What is a Composite Resin (White Filling)? Learn what those dental words mean. The Life of ...

  12. Propaganda: Can a Word Decide a War?

    National Research Council Canada - National Science Library

    Murphy, Dennis M; White, James F

    2007-01-01

    .... The mainstream American press, members of Congress, and other government leaders immediately and loudly condemned these actions as "propaganda" and contrary to the democratic ideals of a free press...

  13. Eyebrow threading: A boon or a bane

    Directory of Open Access Journals (Sweden)

    Sanjeev Gupta

    2011-01-01

    Full Text Available Eyebrow threading is a practice of shaping the eyebrows. Many dermatological complications have been briefly mentioned in various publications. There are scant data regarding the appearance of molluscum in the line of eyebrows after a session of threading. We report a series of eight patients both males (3 and females (5 who had lesions of molluscum in the eyebrow region after threading. The earlier reported cases are only among the females. The present study is highlighting the appearance of molluscum in the region of eyebrow after a session of threading from beauty salon. So, to the best of our knowledge, this is the first report of its kind describing same pathology in males. The rational of reporting this case series is to create awareness among the dermatologists as well as in general population about potential hazards of threading.

  14. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Is My Child at Risk for Early Childhood Tooth Decay? What is a Composite Resin (White Filling)? How Do I Care for My Child's Baby Teeth? Learn what those dental words mean. The Life ...

  15. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Your Family's Oral Health About the AGD Dental care and oral health information you need from the ... a Composite Resin (White Filling)? How Do I Care for My Child's Baby Teeth? Are You Biting ...

  16. A note on a functional inequality

    Directory of Open Access Journals (Sweden)

    Horst Alzer

    1992-01-01

    Full Text Available We prove: If r1,…,rk are (fixed positive real numbers with ∏j=1krj>1, then the only entire solutions φ:ℂ→ℂ of the functional inequality∏j=1k|φ(rjz|≥(∏j=1krj|φ(z|kare φ(z=czn, where c is a complex number and n is a positive integer.

  17. Aframomum aulacocorpus, A. citratum, A. daniellii

    African Journals Online (AJOL)

    Original Paper http://ajol.info/index.php/ijbcs http://indexmedicus.afro.who.int. Utilisation des espèces du genre Aframomum (Aframomum aulacocorpus, A. citratum, A. daniellii) pour le contrôle du poids, le profil lipidique et le statut antioxydant chez les rats Wistar nourris avec une diète athérogène. Louis Raymond NGUELE ...

  18. 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.

  19. 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.......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....

  20. Ventana a la farmacología

    OpenAIRE

    Revista Facultad de, Medicina

    2012-01-01

    Aspirina para prevenir el ataque cardiaco o apoplético / Alteraciones fetales causados por los inhibidores de la enzima de conversión de la angiotensina (eca) / Efectos teratogénicos de los derivados de la vitamina a / Efectos teratogénicos de la warfarina / Algunos avances en farmacología en la última década / ¿Anticonceptivos que previenen el cáncer de seno?

  1. Ventana a la farmacología

    OpenAIRE

    Facultad de Medicina Revista

    1994-01-01

    Aspirina para prevenir el ataque cardiaco o apoplético / Alteraciones fetales causados por los inhibidores de la enzima de conversión de la angiotensina (eca) / Efectos teratogénicos de los derivados de la vitamina a / Efectos teratogénicos de la warfarina / Algunos avances en farmacología en la última década / ¿Anticonceptivos que previenen el cáncer de seno?

  2. Ventana a la farmacología

    Directory of Open Access Journals (Sweden)

    Facultad de Medicina Revista

    1994-07-01

    Full Text Available Aspirina para prevenir el ataque cardiaco o apoplético / Alteraciones fetales causados por los inhibidores de la enzima de conversión de la angiotensina (eca / Efectos teratogénicos de los derivados de la vitamina a / Efectos teratogénicos de la warfarina / Algunos avances en farmacología en la última década / ¿Anticonceptivos que previenen el cáncer de seno?

  3. 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.

  4. A Stark decelerator on a chip

    Science.gov (United States)

    Meek, Samuel A.; Conrad, Horst; Meijer, Gerard

    2009-05-01

    A microstructured array of 1254 electrodes on a substrate has been configured to generate an array of local minima of electric field strength with a periodicity of 120 μm about 25 μm above the substrate. By applying sinusoidally varying potentials to the electrodes, these minima can be made to move smoothly along the array. Polar molecules in low-field seeking quantum states can be trapped in these traveling potential wells. Recently, we experimentally demonstrated this by transporting metastable CO molecules at constant velocities above the substrate (Meek et al 2008 Phys. Rev. Lett. 100 153003). Here, we outline and experimentally demonstrate how this microstructured array can be used to decelerate polar molecules directly from a molecular beam. For this, the sinusoidally varying potentials need to be switched on when the molecules arrive above the chip, their frequency needs to be chirped down in time and they need to be switched off before the molecules leave the chip again. Deceleration of metastable CO molecules from an initial velocity of 360 m s-1 to a final velocity as low as 240 m s-1 is demonstrated in the 15-35 mK deep potential wells above the 5 cm long array of electrodes. This corresponds to a deceleration of almost 105 g, and about 85 cm-1 of kinetic energy is removed from the metastable CO molecules in this process.

  5. Dispersive optomechanics: a membrane inside a cavity

    Energy Technology Data Exchange (ETDEWEB)

    Jayich, A M; Sankey, J C; Zwickl, B M; Yang, C; Thompson, J D; Girvin, S M; Harris, J G E [Department of Physics, Yale University, New Haven, CT (United States); Clerk, A A [Department of Physics, McGill University, Montreal (Canada); Marquardt, F [Department of Physics, Arnold-Sommerfeld-Center for Theoretical Physics and Center for Nanoscience, Muenchen (Germany)], E-mail: jack.harris@yale.edu

    2008-09-15

    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 10{sup 4}-10{sup 5}. The imaginary part of the membrane's index of refraction is found to be {approx}10{sup -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. Worldviews: A blessing or a curse?

    Directory of Open Access Journals (Sweden)

    Bert Olivier

    2012-10-01

    Full Text Available The concept of a worldview resonates with other concepts, such as those of ‘culture’, ‘civilisation’, and ‘way of life’. Arguably, it is a modern phenomenon, the possibility of which was actualised at the dawn of the modern epoch. Nevertheless, in principle, its ‘possibility’ goes back as far as Plato’s Republic. It is Heidegger, however, who is most informative for understanding what a worldview is, as well as why the modern epoch is its time of provenance. Consequently, an analysis of Heidegger’s essay, ‘The time of the world picture’ (or worldview provided the framework within which it was argued that worldviews are both blessings and curses in the current era: blessings, because, as Harries has argued, we have been disabused of the modern idea of one encompassing worldview or ideology, so that one can no longer believe in only a single ’correct’ view of the world; curses, because they bedevil any wellintended attempts at communicating with understanding on issues of common concern. It was the burden of this article to provide a way of addressing this state of affairs with some hope of transcending the causes of alienation and it is again Heidegger who is the source of such a way, through his notion of the ‘fourfold’.

  7. 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

  8. 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.

  9. A sabedoria da democracia

    Directory of Open Access Journals (Sweden)

    Gilson Matilde Diana

    2010-01-01

    Full Text Available http://dx.doi.org/10.5007/1677-2954.2010v9n1p131 Durante a maior parte da história, a democracia foi desprezada como uma forma política inferior – a regra do povo, ou “dos muitos”, era logo identificada como a regra da ralé, da escória. Herdando do povo a volubilidade e a instabilidade, a democracia estava sempre perigosamente próxima do arbítrio e da anarquia, com toda a violência que se costuma associar a isso.

  10. [A zoocentric Capgras syndrome].

    Science.gov (United States)

    Ehrt, U

    1999-01-01

    Capgras syndrome is a delusional misidentification, a phenomenon where a person believes delusionally that another person (in most cases closely related) has been replaced by a double or impostor of identical appearance. It is usually a symptom of a functional psychosis but sometimes it is also associated with organic cerebral dysfunction. We present a case of a 23-year old women who had the delusional belief that her cat had been replaced by the cat of her former boy-friend. Reviewing the literature we found that such a case is very rare. The association between Capgras syndrome and depersonalisation-derealisation phenomena is also pointed out.

  11. 13 CFR Appendix A to Subpart A of... - Appendix A to Subpart A of Part 113

    Science.gov (United States)

    2010-01-01

    .... International Trade Program Small Business Act, sec. 22 and Pub. L. 96-481. Service Corps of Retired Executives... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Appendix A to Subpart A of Part 113 A Appendix A to Subpart A of Part 113 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...

  12. A Chinese Tongue Twister

    Science.gov (United States)

    Hilton, John

    2014-01-01

    When John Hilton was pursuing a master's in education, he took a very influential class from Eleanor Duckworth. She frequently taught and reinforced a concept to the class: "It is very important for teachers to have a chance to watch themselves learn." So when Hilton was hired to teach literature as a college professor, he thought…

  13. 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…

  14. a case study

    African Journals Online (AJOL)

    Assessment of (dis)ability in a prospec tive commercial diver with a hand injury – a case study. A case study in disability. W A J (JAck) MeintJes, MB ChB, DOM, FCPHM (SA) Occ Med, MMed (Occ Med). Specialist, Occupational Medicine, Division of Community Health, Department of Interdisciplinary Health Sciences, ...

  15. A Montessori Odyssey

    Science.gov (United States)

    Hanson, Peter

    2013-01-01

    Forty years ago, Peter Hanson decided to attend the 38th Indian Montessori Training Course. In this article he describes himself as a college-educated generalist who liked kids but was working for little more than minimum wage as a delivery boy. Becoming a teacher in an alternative school seemed like a good move, and a step up without…

  16. 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...

  17. A Hydrostatic Paradox Revisited

    Science.gov (United States)

    Ganci, Salvatore

    2012-01-01

    This paper revisits a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…

  18. A Legacy of Leadership

    Science.gov (United States)

    Rogers, Ibram

    2009-01-01

    This article features Kenneth Avila, Northwestern University's junior centerfielder in baseball. He has volunteered at a Christian youth camp, in a Buddy Ball game with disabled and special education children, and at a sports day at a local elementary school. He has read to children in classrooms at local schools and helped out at a Halloween…

  19. A Polarizing View

    Science.gov (United States)

    Bernard, Rachel; Henegan, Colleen

    2018-01-01

    For many students, the first--and sometimes only--chance to look through a microscope is in high school biology class, where they observe plant and animal cells up close. Even in college, few students use a microscope for a subject other than biology. Thus, it can be a surprise to learn that microscopes are a primary tool used to understand the…

  20. Building a new discipline

    Indian Academy of Sciences (India)

    Lawrence

    memory is when in. Montessori school I was smitten by a set of shining golden unit beads, in rows of ten strung on a wire, ten perfect squares of a hundred, and one cube of a thousand glittering ... My other pleasant memory is when Ms. Wilson, our En- ... ing was dependent on reading a single textbook, with some rare.

  1. A good complaints system

    African Journals Online (AJOL)

    to mediate a complaint, if a patient is unable to resolve their concerns directly with a healthcare professional.[4] Mediation can be a successful way to bring two parties together, and there are numerous professional organisations in South Africa that offer an impartial mediation service. GUEST EDITORIAL. A good complaints ...

  2. Without a Voice

    Science.gov (United States)

    Pennamacoor, Carol

    2007-01-01

    Selective Mutism (SM), normally discovered at a young age, is a selective anxiety disorder in which a child demonstrates a persistent lack of speech in one or more social settings, notably in school, despite his or her ability to speak comfortably at home. In this article, the author presents Betsy, a child who was diagnosed with SM and was helped…

  3. 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)

  4. Solubilization of a dendrimer into a microemulsion.

    Science.gov (United States)

    Nir, Ido; Aserin, Abraham; Libster, Dima; Garti, Nissim

    2010-12-23

    The present work investigates, for the first time, a system comprising a dendrimer incorporated into the water core of water-in-oil (W/O) microemulsion (ME). A second generation (G-2) poly(propyleneimine) dendrimer (PPI) was solubilized into W/O ME composed of AOT (sodium bis(2-ethylhexyl)sulfosuccinate), heptane, and water. Such a model system possessing the benefits of both dendrimers and ME, can potentially offer superior control of drug administration. The localization of PPI within the system, its specific interactions with the components of the carrier, and its effect on the ME structure was explored by SAXS, DSC, ATR-FTIR, and electrical conductivity measurements. Considerable water binding by PPI, accompanied by partial dehydration of AOT polar heads, was detected by ATR-FTIR and DSC analysis, suggesting that PPI acted as a "water pump". In addition, SAXS measurements showed periodicity increase and disordering of the droplets. Hence, localization of PPI within the core and interfacial regions of the droplets was assumed. Direct electrostatic interactions between PPI and the sulfonate group were not noticed, since the dendrimer molecules were mostly not protonated in the current basic environment at pH 12. However, slight hydrogen bonding between PPI and the S=O groups allowed the dendrimer to behave as a "spacer" between sodium and sulfonate ions. This affected the electrical conductivity behavior of the system, revealing that PPI favored the percolation process. Most likely, PPI decreased the rigidity of the interfacial layer, facilitating the diffusion of sodium ions through the channels. The characterized model system can be advantageously utilized to design specific delivery vehicles, allowing administration of dendrimers as a therapeutic agent from host MEs.

  5. 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

  6. Whistleblowing: a legal commentary.

    Science.gov (United States)

    Cornock, Marc

    2011-10-01

    This article examines the legal position of a nurse who believes that a colleague is performing below the level of competence required, witnesses inappropriate action by a colleague, or who believes that the care environment is putting patients at risk.

  7. A major safety overhaul

    CERN Multimedia

    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.

  8. A Misleading Trismus

    Directory of Open Access Journals (Sweden)

    A. Galzerano

    2011-01-01

    Full Text Available We report the case of a 73-year-old women admitted to ICU with a diagnosis of tetanum supported by a mild trismus and treated with potentially unsafe drugs until the correct diagnosis was made.

  9. What's a Birthmark?

    Science.gov (United States)

    ... Hemangiomas One kind of hemangioma is called a superficial hemangioma (sometimes called a strawberry hemangioma ). If you ... name from the fruit, you're right. A superficial hemangioma is bright red and sticks out of ...

  10. A Single Atom Antenna

    International Nuclear Information System (INIS)

    Trinter, Florian; Williams, Joshua B; Weller, Miriam; Waitz, Markus; Pitzer, Martin; Voigtsberger, Jörg; Schober, Carl; Kastirke, Gregor; Müller, Christian; Goihl, Christoph; Burzynski, Phillip; Wiegandt, Florian; Wallauer, Robert; Kalinin, Anton; Schmidt, Lothar Ph H; Schöffler, Markus S; Jahnke, Till; Dörner, Reinhard; Chiang, Ying-Chih; Gokhberg, Kirill

    2015-01-01

    Here we demonstrate the smallest possible implementation of an antenna-receiver complex which consists of a single (helium) atom acting as the antenna and a second (neon) atom acting as a receiver. (paper)

  11. 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 ...

  12. A dictionary is a tool, a good dictionary is a monofunctional tool

    DEFF Research Database (Denmark)

    Bergenholtz, Henning; Bergenholtz, Inger

    2011-01-01

    A dictionary is a tool. Most dictionaries are constructed as polyfunctional tools: they are expected to be used by everyone in any kind of user situation with communicative and cognitive problems. Good tools are not polyfunctional. If you go to a shop and ask for a saw, you have to specify first...... of dictionary conceptions for monofunctional dictionaries. We will do this with examples from a lexicographical music data base which gives rise to two monofunctional dictionaries and a third polyfunctional dictionary of a special kind. The lexicographical music data base gives rise to a collection of music...... dictionaries on expressions from the world of classical music whereas it contains only little information on pop, rock or jazz terms. The first monofunctional dictionary is conceived for reception, e.g. reading a text on a musical topic or reading a music score. Not many people know what a mbira is or what...

  13. 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.

  14. 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

  15. 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...

  16. 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 t...... – mirrored in online memorial sites – that transform the dead child into a being with whom an altered relationship may be built, maintained and developed so that the bereaved can, eventually, integrate the dead into his or her ongoing life.......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 graves...

  17. 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.

  18. A sound sleep

    OpenAIRE

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

    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...

  19. A power measuring device

    International Nuclear Information System (INIS)

    As, R. van.

    1985-01-01

    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.)

  20. '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....

  1. A Case of a Laryngeal MALT Lymphoma in a Patient with a History of Gastric MALT

    Directory of Open Access Journals (Sweden)

    Mark Ashamalla

    2015-01-01

    Full Text Available We are reporting a case of a 62-year-old African American woman with a history of gastric MALT lymphoma successfully treated with radiation who presented with a laryngeal MALT lymphoma 4 years after her original diagnosis. She received definitive radiation with a complete response. The case presented is unique for the rare presentation of a MALT lymphoma in the larynx, especially in light of the patient’s previously treated gastric MALT lymphoma years ago.

  2. Bibliografía

    OpenAIRE

    2013-01-01

    Fuentes Primarias A. C. S. F. – Archivo del Convento de San Francisco A. G. N. – Archivo General de la Nación Escribanos CARVONERO DE ALVA, A., 1657 – protocolo 261, f. 1386. FIGUEROA de, M. A., 1643 – protocolo 590, f. 405 vta. FIGUEROA de, M. A., 1654 – protocolo 616, f. 1079. FIGUEROA de, M. A., 1662 – protocolo 641, f. 2154. FIGUEROA de, M. A., 1665 – protocolo 652, f. 1313-1314. GARCÍA, N., 1666 – protocolo 706, f. 677 vta. GÓMEZ DE BAEZA, R., 1597-1598 – protocolo 56, f. 644. HERNÁNDEZ,...

  3. Living-donor kidney transplant from a type a donor to a type a subgroup recipient.

    Science.gov (United States)

    Ueda, Norichika; Nishimura, Kenji; Yoshida, Yasuyuki; Hirai, Toshiaki; Kishikawa, Hidefumi; Ichikawa, Yasuji

    2015-04-01

    Type A subgroup is rare in Japan, and kidney transplant to a type A subgroup recipient is rare worldwide. A 65-year-old man presented for living-donor kidney transplant. Blood group testing showed that his wife (kidney donor) had blood group type A. The patient (recipient) had a type A subgroup because reverse blood grouping showed a weak reaction with A1 antigen. Further testing showed that the recipient had type A subgroup between Ax and Ael because adsorption elution experiments and flow cytometry showed a few A antigens that were not detected on forward grouping, and DNA analysis was not consistent with Ael. The patient was given a milder protocol for immunosuppressive preoperative therapy than typically used for ABO-incompatible kidney transplant; mycophenolate mofetil and prednisolone were started 3 weeks and cyclosporine 2 weeks before transplant, rituximab (100 mg) was given once, and double filtration plasmapheresis and plasma exchange were not used. Follow-up at 9 months after transplant showed stable clinical status and no allograft rejection. In summary, the present case showed that when type A subgroup recipient has low level of anti-A1 antibody and is receiving a kidney transplant from a blood type A donor, milder immunosuppressive preoperative therapy appears safe.

  4. Shaping a Scientific Self

    DEFF Research Database (Denmark)

    Andrade-Molina, Melissa; Valero, Paola

    In this paper we illustrate how a truth circulates within social discourse. We examine a particular truth reproduced within science, that is: through the understanding of Euclid’s axioms and postulates a person will gain the access to all human knowledge. We deploy a discourse analysis that helps...... 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...

  5. 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...... boundaries are found on a smoothed novelty measure, calculated from the self-similarity matrix. All the steps of the model have been accompanied with an informal evaluation, and the final system is tested on a variety of rhythmic songs with good results. The paper introduces a new feature that is shown...

  6. A Blue Lagoon Function

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2007-01-01

    We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....

  7. 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.

  8. A sustentabilidade e a fenomenologia do pertencer

    Directory of Open Access Journals (Sweden)

    Verônica Maria Bezerra Guimarães

    2017-06-01

    Full Text Available Trata-se de um estudo de interdisciplinaridade na sustentabilidade, com base em ciências sociais e jurídicas, proveniente do Doutorado em Desenvolvimento Sustentável no CDS/UnB, onde se refletiu sobre modelos de sustentabilidade do povo indígena kaiowá-guarani do sul do Mato Grosso do Sul. A teoria situa-se no âmbitos da: fenomenologia, pertencimento e topofilia. Foi realizado trabalho de campo, em 2014, em três terras: Te´ýkue, Sucurui´y e Jatayvary onde adotaram-se técnicas de observação direta, conversas, depoimentos gravados e transcritos, diários de campo, caminhadas e registros fotográficos. A ideia de pertencer à terra, vivenciada pelos kaiowá-guarani, revela uma importante contribuição a “ciência da sustentabilidade”.

  9. A Conservative Approach to a Peripheral Ameloblastoma

    Directory of Open Access Journals (Sweden)

    Rocco Borrello

    2016-01-01

    Full Text Available Peripheral Ameloblastoma (PA is the rarest variant of ameloblastoma. It differs from the other subtypes of ameloblastoma in its localization: it arises in the soft tissues of the oral cavity coating the tooth bearing bones. Generally, it manifests nonaggressive behavior and it can be treated with complete removal by local conservative excision. In this study we report a case of PA of the maxilla in a 78-year-old female patient and we describe the four different histopathological patterns revealed by histological examination. After local excision and diagnosis, we planned a long term follow-up: in one year no recurrence had been reported. The choice of treatment is illustrated in Discussion.

  10. A white book for a greener future

    International Nuclear Information System (INIS)

    2016-01-01

    The energy transition law promulgated in August 2015 and the Paris Agreement in December 2016 have marked the necessity to build an energy mix with a growing up importance given to renewable energy sources. The French Gas Association (AFG) and the gas industry have joint their efforts to promote the advantages of natural gas as a support to the development of renewable energies. The publication of the AFG white book on September 27 is an illustration of this promotional action. This article provides an overview of the 10 proposals of this white book: 1 - promoting all renewable energy sources; 2 - Making energy transition in the regions a success; 3 - Improving air quality thanks to clean mobility; 4 - Reducing greenhouse gas emissions; 5 - Reducing energy consumption in accommodations; 6 - Fighting fuel poverty; 7 - Contributing to the energy security supplies of France; 8 - Making energy taxation more efficient; 9 - Storing energy while accompanying renewable energy sources development; 10 - Promoting innovation

  11. A natureza pode modelar a cidade?

    Directory of Open Access Journals (Sweden)

    Jorge Rebollo Squera

    2007-12-01

    Full Text Available Com a consolidação da questão ambiental no planejamento regional e urbano constata-se a necessidade de integrar as propostas de desenvolvimento, com instrumentos de ordenamento territorial que levem em consideração os condicionantes e a sustentabilidade dos recursos naturais. A legislação brasileira, a partir da Constituição Federal de 1988, definiu o ordenamento territorial como parte integrante de toda política de desenvolvimento, com ênfase na preservação do meio ambiente. Na década de 1991-2000, o Estado de Santa Catarina desenvolveu os programas “Zoneamento Ecológico Econômico” e “Gerenciamento Costeiro” que incorpora essa visão integrada de desenvolvimento e ordenamento físico-territorial. Nesses programas surgem propostas de ocupação e organização dos espaços urbanos e regionais para duas unidades paisagísticas muito presentes no Estado: os vales e o litoral. Baseado na utilização gradativa de densidades urbanas adequadas à vulnerabilidade dos recursos naturais surge um novo modelo dos volumes e espaços urbanos. Neste trabalho discutimos como os aspectos ambientais incorporados na elaboração de planos modelam a cidade. Também, o planejamento territorial, ao atender às condicionantes do ambiente natural, possibilitará uma ocupação mais equilibrada, com alternância de espaços urbanizados sustentáveis e áreas de diversos graus de conservação, agrícolas, usos especiais, dentre outras.

  12. Melatonin as a radioprotective agent: a review

    International Nuclear Information System (INIS)

    Vijayalaxmi; Reiter, Russel J.; Tan, D.-X.; Herman, Terence S.; Thomas, Charles R.

    2004-01-01

    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 e aq - 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

  13. A Modern Dunciad A Modern Dunciad

    Directory of Open Access Journals (Sweden)

    Anita Flanders Rebelo

    2008-04-01

    Full Text Available "Push-button war demands a woman's touch!" shrills Nason's twentieth century goddess Dullness, (in his book length poetic plagiarism of Pope's mock epic Dunciad, as she reestablishes her Empire in the modern New World by masking, cancelling, and attacking Progress and Liberty in a lustful attempt to destroy the Moral and Emotional content of poetry. She sluttishly breeds and fosters the Dunces of the literary kingdom of today, (Pope's Dunces were the poet Laureates of his day, and sallies brazenly everywhere in the company of her muses Self-Service, Smuggnes, sadism, and "sweet Anality", so light and fair,/ Enlaced with tender plaits her public hair".

  14. "One Wears a Melon, Another a Cylinder"

    DEFF Research Database (Denmark)

    Shaw, Philip; Caudery, Tim; Petersen, Margrethe

    that perceptible change is nevertheless not only towards greater fluency but also towards native-speaker-like norms of usage in such areas as pronunciation, tense usage and even vocabulary. The title's example of effective Euro-English names for hat types is therefore not characteristic. In an environment where......This paper analyses interviews with exchange students in four Scandinavian universities and conducts a longitudinal analysis of three picture descriptions spread over a twenty-week period. It briefly describes the opportunities available to exchange students for language learning, both English...... interaction is almost entirely with non-natives this is an interesting development....

  15. A view to a (staged) kill?

    DEFF Research Database (Denmark)

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

    2015-01-01

    . Moreover, differences in expression of one’s fundamental values toward wildlife may help to explain differences found in views. This type of recreational hunting challenges traditional hunting/anti-hunting arguments, such as hunting being acceptable when based on sustained yield ‘harvest’ principles...... 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...

  16. Hotelier: a Passion or a Profession?

    Directory of Open Access Journals (Sweden)

    Agung Gita Subakti

    2013-05-01

    Full Text Available The history of hotels is intimately connected to that of civilizations. Or rather, it is a part of that history. Through years and time, many people are making their mark in the hotel industry by gaining the title as a Hotelier. Not just nationwide but they placed their footsteps throughout the world and became leading people in the Hospitality industry. The aim of this paper is to overview some of the people who had achieve the reputation as an Hotelier: globally recognized, set up their set of high quality standard, developing international brand and be able to sustain and succeed worldwide.

  17. A view to a (staged) kill?

    DEFF Research Database (Denmark)

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

    2015-01-01

    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 (web....... Moreover, differences in expression of one’s fundamental values toward wildlife may help to explain differences found in views. This type of recreational hunting challenges traditional hunting/anti-hunting arguments, such as hunting being acceptable when based on sustained yield ‘harvest’ principles...

  18. UNA TEORÍA SUREÑA

    Directory of Open Access Journals (Sweden)

    Robert William Connell

    2004-01-01

    Full Text Available Este artículo es un intento de comprensión de la situación pasada y presente de la sociología en relación con la sociedad global. Propone una estrategia para el desarrollo de la sociología como una ciencia democrática en la era de la globalización corporativa, resaltando la importancia de las perspectivas producidas más allá de la metrópolis.

  19. Between a Map and a Data Rod

    Science.gov (United States)

    Teng, William; Rui, Hualan; Strub, Richard; Vollmer, Bruce

    2015-01-01

    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 objectivesconstraints. 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 years worth of time series for hourly data (9,000 time steps) in 90 seconds. Our approach is a specific implementation of

  20. A Tate Gallery : de Millbank a Bankside

    OpenAIRE

    Baixa, Célia Maria da Costa

    2016-01-01

    Tese de doutoramento, Estudos de Literatura e de Cultura (Cultura e Comunicação), Universidade de Lisboa, Faculdade de Letras, 2016 Esta tese explora os contextos de evolução da Tate Gallery em Londres desde a sua origem no século XIX até ao presente. Através de uma abordagem multidisciplinar filiada nos Estudos Culturais este estudo tem como objetivo dar um contributo para a análise das transformações da cultura e da sociedade assim como fornecer um enquadramento para estudar conceitos co...

  1. A rationale for a museum of health

    Directory of Open Access Journals (Sweden)

    Farzaneh Yousefi

    2015-11-01

    Full Text Available The museum of health is a place that presents health science and human body and any other subjects that can affect human health. In this museum visitors can learn the mechanisms and functions of human body and learn how to protect and take care of their bodies. They can also learn several diseases and their consequences on human body and how to fight against them. This museum is a big step for improvement of general society health level by increasing society’s health knowledge. In this article structure, departments and also benefits of the health museum are evaluated.

  2. A Glass without a Bottom’

    DEFF Research Database (Denmark)

    Karpova, Yulia

    2017-01-01

    In the 1950s, Soviet decorative artists, under the influence of the incipient industrial design profession, chose utility, modesty and the ability for mass reproduction as the chief criteria for their work. Some critics envisioned a confluence of decorative art and industrial design. However, from...... to the study of Soviet design by identifying a specific phenomenon of the 1960s, for which I offer the term ‘neodecorativism’. It traces the Soviet decorative art’s turn from ‘honest objects’ to provocative objects that transcended the logic of mass production and questioned the principles of post-war Soviet...... aesthetics....

  3. A strategic approach to a green economy.

    Science.gov (United States)

    Trumka, Richard L

    2009-01-01

    The crash has happened and we face dual market failures: climate change and the greatest economic crisis of our lifetimes. American labor believes that we must have a strategic approach to greening the economy centered on domestic investment in new technologies, the creation of good jobs, and leading a shared international response to both these issues. The nay-sayers are the same financial and industrial interests that advised the world economy into chaos. Their advice to us is more of the same: no rules, no regulations, free markets, and free trade. But now is the time for real change.

  4. Transvestism as a Symptom: A Case Series

    Science.gov (United States)

    Anupama, M.; Gangadhar, K. H.; Shetty, Vandana B.; Dip, P. Bhadja

    2016-01-01

    Transvestism, commonly termed as cross-dressing, means to dress in the clothing of opposite sex. We describe a series of three cases with transvestism as one of their primary complaints. The discussion sheds light on the various ways in which transvestism as a symptom can present in Psychiatry. In the first two cases, there was lower intelligence. In first and third case, there were other paraphilia along with transvestism. Second case had co-morbid obsessive-compulsive disorder (OCD) and had good response to selective serotonin reuptake inhibitor (SSRI). PMID:27011411

  5. A Little Salesmanship "Grows" a Long Way

    Science.gov (United States)

    Montas, Leah

    2012-01-01

    Goshen Elementary PTA's membership shrank the first year the author was PTA president. In the back of her mind, she was bothered by the fact that their membership numbers had dropped. So, after she attended a regional session with her vice president on growing membership, she got the courage to propose something different. They discussed with…

  6. "Schemas: A Way into a Child's World"

    Science.gov (United States)

    Arnold, Cath

    2015-01-01

    This paper explores some of the learning of a young child from the age of 8-23 months and considers how identifying schemas or repeated patterns of actions can inform our pedagogic responses. Gabriella was observed using naturalistic observation methods, at home, at her grandparents' home, at parks and using early childhood services. Narrative…

  7. Parallel careers: a parasitologist and a vet.

    Science.gov (United States)

    Wright, Ian

    2017-09-02

    Ian Wright heads the European Scientific Counsel Companion Animal Parasites (ESCCAP) UK and Ireland, which involves some international travel. He and his wife are also practice owners and they have two children. He admits that work-life balance can be a challenge. British Veterinary Association.

  8. Instructional technology: A tool or a panacea?

    Science.gov (United States)

    Kimmel, Howard; Deek, Fadi

    1996-03-01

    It is time to recognize that educational technology cannot be considered a panacea for educational reform. Technology, when properly used, can be a very effective tool for improving and enhancing instruction and learning experiences in the content areas. However, incorporation of electronic tools, such as computers and videodiscs, into classrooms must be accompanied by systemic change in the educational process. Successful utilization of technology depends on how we provide teachers with the necessary environment for training, tools for instruction, and technology evaluation skills. This paper examines some of the misuses of technology and then explores the appropriate use of technology in the context of current educational reform. The focus is on the integration of technology in the educational process that provides a learning environment allowing discovery and creativity through the use of computer visualizations. The teacher is seen as the essential element, requiring a solid foundation in the general applications of technology, and the ability to evaluate and select systems that are effective and efficient for specific applications.

  9. On Embedding a Semigroup in a Group

    Indian Academy of Sciences (India)

    ias

    algebra textbook, as well as one on number theory, and also had an interest in the history of mathematics”. Mal- cev gave an example to show that there are cancella- tive semigroups which cannot be embedded in a group. Commenting on Sushkevich's persistence with his erro- neous ideas even after being proved wrong ...

  10. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... InfoBites Quick Reference Learn more Pregnancy and Oral Health What is Dental Amalgam (Silver Filling)? Temporomandibular Joint ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  11. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... 2018 About | Contact InfoBites Quick Reference Learn more Oral Health and Overal Health Headaches and Jaw Pain? Check ... Tooth Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  12. A case of a 'lost' nasogastric tube.

    Science.gov (United States)

    Sankar, V; Shakeel, M; Keh, S; Ah-See, K W

    2012-12-01

    To present the case of a 'lost' nasogastric tube and to highlight the importance of imaging and/or chest X-ray after nasogastric tube insertion, especially in unreliable patients. A 50-year-old man, undergoing radiotherapy treatment for squamous cell carcinoma of the tongue base, was admitted for pain control and nasogastric tube feeding. This patient required multiple nasogastric tubes over a two-week period. The patient repeatedly denied pulling the nasogastric tube out and we were unable to establish the exact mode of nasogastric tube removal. On one such occasion another tube was inserted and a check X-ray showed two feeding tubes; the latest one was lying in the left main bronchus and the old nasogastric tube was observed in the oesophagus, with its upper end jutting above the hypopharynx. It was apparent that the patient had somehow cut the tube and swallowed it. This case not only illustrates the importance of flexible nasendoscopy and/or chest X-ray for checking the position of the nasogastric tube, but also highlights that some patients are not tolerant of nasogastric tubes. The use of nasogastric tubes should be avoided in these patients to prevent any self-inflicted injury.

  13. A NOVEL PROTON TRANSFER COMPOUND (A NEW ...

    African Journals Online (AJOL)

    Preferred Customer

    intermolecular proton transfer from (MoO4H2) to (OHRNH2) results in the formation of a new molybdate salt that ... KEY WORDS: Proton transfer, Molybdate salt, X-ray structure, MoO2(acac)2, 2-Amino-2-methyl-1-propanol ..... data can be obtained free of charge on application to The Director, CCDC, 12 Union Road,.

  14. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... Contact InfoBites Quick Reference Learn more Children's Oral Health What is Baby Bottle Tooth Decay? Temporomandibular Joint ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  15. Consciousness Is a Thing, Not a Process

    Directory of Open Access Journals (Sweden)

    Susan Pockett

    2017-12-01

    Full Text Available The central dogma of cognitive psychology is ‘consciousness is a process, not a thing’. Hence, the main task of cognitive neuroscientists is generally seen as working out what kinds of neural processing are conscious and what kinds are not. I argue here that the central dogma is simply wrong. All neural processing is unconscious. The illusion that some of it is conscious results largely from a failure to separate consciousness per se from a number of unconscious processes that normally accompany it—most particularly focal attention. Conscious sensory experiences are not processes at all. They are things: specifically, spatial electromagnetic (EM patterns, which are presently generated only by ongoing unconscious processing at certain times and places in the mammalian brain, but which in principle could be generated by hardware rather than wetware. The neurophysiological mechanisms by which putatively conscious EM patterns are generated, the features that may distinguish conscious from unconscious patterns, the general principles that distinguish the conscious patterns of different sensory modalities and the general features that distinguish the conscious patterns of different experiences within any given sensory modality are all described. Suggestions for further development of this paradigm are provided.

  16. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... InfoBites Quick Reference Learn more Pregnancy and Oral Health Temporomandibular Joint Disorder What is Orofacial Pain? What ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | RSS About AGD | Contact AGD | Site Map | Reprints ...

  17. Life of a Tooth: A Visual Timeline

    Medline Plus

    Full Text Available ... InfoBites Quick Reference Learn more Pregnancy and Oral Health What is Orofacial Pain? Check Menstrual Calendar for ... Home | InfoBites | Find a Dentist | Your Family's Oral Health | Newsroom | RSS About AGD | Contact AGD | Site Map | ...

  18. A Narrative Account of a Teacher Community

    Science.gov (United States)

    Moate, Josephine

    2014-01-01

    This narrative account draws on dialogic approaches to education to critically reflect on teachers' expressed pedagogic thinking in community. The context for the study is a teacher community in Central Finland comprising teachers from pre-primary to upper secondary contexts. The shared interest of the community is in the foreign-language…

  19. A Business School on a World Mission

    Science.gov (United States)

    Totterman, Henrik

    2013-01-01

    The idea of "doing good while doing well" is hardly new. But the Y Generation's response to it is different. They are literally taking on a youth revolution that extends from one part of the world to the other, while changing the conversation around social good and entrepreneurship. Hult International Business School is one of few…

  20. Between a Rock and a Soft Place

    Science.gov (United States)

    Denig, Stephen J.

    2012-01-01

    Catholic colleges and universities are caught between two competing pressures. On the one side the church hierarchy, especially the Vatican, wants to make certain that these institutions of higher learning remain faithful to the intellectual tradition and the teachings of the church. On the other side these institutions exist in a postmodern world…