WorldWideScience

Sample records for ripening-induced polygalacturonase related

  1. Analysis of papaya cell wall-related genes during fruit ripening indicates a central role of polygalacturonases during pulp softening.

    Directory of Open Access Journals (Sweden)

    João Paulo Fabi

    Full Text Available Papaya (Carica papaya L. is a climacteric fleshy fruit that undergoes dramatic changes during ripening, most noticeably a severe pulp softening. However, little is known regarding the genetics of the cell wall metabolism in papayas. The present work describes the identification and characterization of genes related to pulp softening. We used gene expression profiling to analyze the correlations and co-expression networks of cell wall-related genes, and the results suggest that papaya pulp softening is accomplished by the interactions of multiple glycoside hydrolases. The polygalacturonase cpPG1 appeared to play a central role in the network and was further studied. The transient expression of cpPG1 in papaya results in pulp softening and leaf necrosis in the absence of ethylene action and confirms its role in papaya fruit ripening.

  2. Analysis of Quality-Related Parameters in Mature Kernels of Polygalacturonase Inhibiting Protein (PGIP) Transgenic Bread Wheat Infected with Fusarium graminearum.

    Science.gov (United States)

    Masci, Stefania; Laino, Paolo; Janni, Michela; Botticella, Ermelinda; Di Carli, Mariasole; Benvenuto, Eugenio; Danieli, Pier Paolo; Lilley, Kathryn S; Lafiandra, Domenico; D'Ovidio, Renato

    2015-04-22

    Fusarium head blight, caused by the fungus Fusarium graminearum, has a detrimental effect on both productivity and qualitative properties of wheat. To evaluate its impact on wheat flour, we compared its effect on quality-related parameters between a transgenic bread wheat line expressing a bean polygalacturonase inhibiting protein (PGIP) and its control line. We have compared metabolic proteins, the amounts of gluten proteins and their relative ratios, starch content, yield, extent of pathogen contamination, and deoxynivalenol (DON) accumulation. These comparisons showed that Fusarium significantly decreases the amount of starch in infected control plants, but not in infected PGIP plants. The flour of PGIP plants contained also a lower amount of pathogen biomass and DON accumulation. Conversely, both gluten and metabolic proteins were not significantly influenced either by the transgene or by fungal infection. These results indicate that the transgenic PGIP expression reduces the level of infection, without changing significantly the wheat seed proteome and other quality-related parameters.

  3. Molecular cloning and functional analysis of three genes encoding polygalacturonase-inhibiting proteins from Capsicum annuum, and their relation to increased resistance to two fungal pathogens

    Science.gov (United States)

    Polygalacturonase-inhibiting proteins (PGIPs) are plant cell wall glycoproteins that can inhibit fungal endopolygalacturonases (PGs). Inhibiting by PGIPs directly reduces potential PG activity in specific plant pathogenic fungi, reducing their aggressiveness. Here, we isolated and functionally chara...

  4. Physico-chemical characteristics of immobilized polygalacturonase ...

    African Journals Online (AJOL)

    Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger) (SA6), partially purified, characterized and immobilized by entrapment using calcium alginate. The polygalacturonase showed two bands on sodium dodecyl sulfate polyacryamide gel electrophoresis (SDS-PAGE) suggesting an “endo and exo” ...

  5. Purification, Characterization and Application of Polygalacturonase from Aspergillus niger CSTRF

    Directory of Open Access Journals (Sweden)

    Arotupin Daniel Juwon

    2012-09-01

    Full Text Available Aims: The research was carried out to study the purification, characterization and application of polygalacturonase fromAspergillus niger CSTRF.Methodology and Results: The polygalacturonase (PG from the fungus was purified by ammonium sulphate precipitation and dialysed. The resulting fraction of the enzyme was further separated by molecular exclusion and ion exchange chromatography. The enzyme was purified 28.19 fold with a yield of approximately 69 % following purificationwith SP C-50. It has a relative molecular weight of 79,430 daltons and markedly influenced by temperature, pH and substrate concentrations of reactions with optimum activity at 35 °C, pH 4.0 and 8 mg/mL respectively. The PG was heat stable over a broad range of temperatures. Line weaver-Burk plot for the apparent hydrolysis of pectin showed approximately Km value of 2.7 mg/mL. The activity of the enzyme was enhanced by Na+, Ca2+, Mg2+ and Zn2+, while EDTA, PbCl2, HgCl2 and IAA were inhibitory. The ability of the purified enzyme to clarify fruit juice was also investigated.Conclusion, significance and impact of the study: This study revealed that polygalacturonase possesses properties for clarification of fruit juice and by extension bioprocessing applications.

  6. Bean polygalacturonase inhibitor protein-1 (PGIP-1) inhibits polygalacturonases from Stenocarpella maydis

    CSIR Research Space (South Africa)

    Berger, DK

    2000-07-01

    Full Text Available Stenocarpella maydis, a fungal pathogen of maize, produced polygalacturonases (PGs) when grown on pectin or maize cell walls. An extract from bean (Phaseolus vulgaris L.) which contained an active inhibitor of Aspergillus niger PG, also inhibited S...

  7. Expression and functional analysis of polygalacturonase gene ...

    African Journals Online (AJOL)

    DR TONUKARI

    2012-02-02

    Feb 2, 2012 ... As one of the cell wall-degrading enzymes, polygalacturonase involves in pathogenicity and virulence in a number of host .... plants and bacteria were carried out using ClustalX (version 1.81) .... using plastic molds. Ultrathin ...

  8. Characterization of polygalacturonases from fruit spoilage Fusarium ...

    African Journals Online (AJOL)

    The most chemical compounds caused moderate inhibitory effect except benzoic and citric acids which had strong inhibitory effect on the polygalacturonases. The benzoic and citric acids were used as antifungal compounds for F. oxysporum and A. tubingensis. The citric acid was found to be more effective against fungal ...

  9. Characterization of polygalacturonases produced by Geotrichum candidum

    Czech Academy of Sciences Publication Activity Database

    Illková, K.; Zemková, Z.; Omelková, J.; Flodrová, Dana; Benkovská, Dagmar; Vadkertiová, R.; Stratilová, E.

    2011-01-01

    Roč. 105, č. 18 (2011), s1014-s1015 ISSN 0009-2770. [Meeting on Chemistry and Life /5./. 14.09.2011-16.09.2011, Brno] Institutional research plan: CEZ:AV0Z40310501 Keywords : polygalacturonases * Geotrichum Subject RIV: CB - Analytical Chemistry, Separation

  10. A colorimetric method to quantify endo-polygalacturonase activity.

    Science.gov (United States)

    Torres, Sebastián; Sayago, Jorge E; Ordoñez, Roxana M; Isla, María Inés

    2011-02-08

    We report a new colorimetric assay to quantify endo-polygalacturonase activity, which hydrolyzes polygalacturonic acid to produce smaller chains of galacturonate. Some of the reported polygalacturonase assays measure the activity by detecting the appearance of reducing ends such as the Somogyi-Nelson method. As a result of being general towards reducing groups, the Somogyi-Nelson method is not appropriate when studying polygalacturonase and polygalacturonase inhibitors in plant crude extracts, which often have a strong reducing power. Ruthenium Red is an inorganic dye that binds polygalacturonic acid and causes its precipitation. In the presence of polygalacturonase, polygalacturonic acid is hydrolyzed bringing about a corresponding gain in soluble Ruthenium Red. The described assay utilizes Ruthenium Red as the detection reagent which has been used previously in plate-based assays but not in liquid medium reactions. The new method measures the disappearance of the substrate polygalacturonic acid and is compared to the Somogyi-Nelson assay. The experimental results using lemon peel, a fern fronds and castor leaf crude extracts demonstrate that the new method provides a way to the quickly screening of polygalacturonase activity and polygalacturonase inhibitors in plant crude extracts containing high amounts of reducing power. On the other hand, the Ruthenium Red assay is not able to determine the activity of an exo-polygalacturonase as initial velocity and thus would allow the differentiation between endo- and exo-polygalacturonase activities. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. After-ripening induced transcriptional changes of hormonal genes in wheat seeds: the cases of brassinosteroids, ethylene, cytokinin and salicylic acid.

    Directory of Open Access Journals (Sweden)

    Vijaya R Chitnis

    Full Text Available Maintenance and release of seed dormancy is regulated by plant hormones; their levels and seed sensitivity being the critical factors. This study reports transcriptional regulation of brassinosteroids (BR, ethylene (ET, cytokinin (CK and salicylic acid (SA related wheat genes by after-ripening, a period of dry storage that decays dormancy. Changes in the expression of hormonal genes due to seed after-ripening did not occur in the anhydrobiotic state but rather in the hydrated state. After-ripening induced dormancy decay appears to be associated with imbibition mediated increase in the synthesis and signalling of BR, via transcriptional activation of de-etiolated2, dwarf4 and brassinosteroid signaling kinase, and repression of brassinosteroid insensitive 2. Our analysis is also suggestive of the significance of increased ET production, as reflected by enhanced transcription of 1-aminocyclopropane-1-carboxylic acid oxidase in after-ripened seeds, and tight regulation of seed response to ET in regulating dormancy decay. Differential transcriptions of lonely guy, zeatin O-glucosyltransferases and cytokinin oxidases, and pseudo-response regulator between dormant and after-ripened seeds implicate CK in the regulation of seed dormancy in wheat. Our analysis also reflects the association of dormancy decay in wheat with seed SA level and NPR independent SA signaling that appear to be regulated transcriptionally by phenylalanine ammonia lyase, and whirly and suppressor of npr1 inducible1 genes, respectively. Co-expression clustering of the hormonal genes implies the significance of synergistic and antagonistic interaction between the different plant hormones in regulating wheat seed dormancy. These results contribute to further our understanding of the molecular features controlling seed dormancy in wheat.

  12. Product optimization, purification and characterization of a novel polygalacturonase produced by Macrophomina phaseolina

    Directory of Open Access Journals (Sweden)

    Saeed Aminzadeh

    2013-01-01

    Full Text Available Introduction: Production of a novel polygalacturonase (PG active at pH = 3.0 and suitable to be used in fruit juice industries from Macrophomina phaseolina was evaluated. Suitable carbon, nitrogen and phosphorous forms were determined and the condition was optimized for higher PG production. Materials and methods: Macrophomina phaseolina was cultured in so called production medium. The secretome was separated from fungal cells and polygalacturonase was isolated via column chromatography. The biochemical activity of both secretome and isolated polygalacturonase were assayed calorimetrically. The production of polygalacturonase was optimized via changes in culture medium in terms of contents, pH and temperature and Taguchi analysis of data. Enzyme kinetics was partially performed followed by the determination of pH and temperature stability. Results: A range of sugars except glucose and chitin demonstrated to improve the PG production. Ammonium sulfate and peptone demonstrated to be suitable nitrogen sources. Amongst phosphorous sources, dipotassium hydrogen phosphate had the greatest effect. Taguchi’s orthogonal array demonstrated that pH, temperature, ammonium sulfate and trace elements had significant effect on PG production. Furthermore, mean comparisons showed that the optimum condition achieved at pH 6.0, 35 °C, 2 g.l-1 ammonium sulfate and 2 mg.l-1 trace elements. Discussion and conclusion: The purified PG with a relative molecular mass of 70 kDa was demonstrated its highest activity at pH = 3, and 30 °C. Amongst tested cations and chemicals, Fe2+ improved the enzyme activity by 2 fold, while the secretome responded differently.

  13. Partially purified polygalacturonase from Aspergillus niger (SA6 ...

    African Journals Online (AJOL)

    Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger) (SA6), partially purified and characterized. The PG showed two bands on SDS-PAGE suggesting an “endo and exo PG with apparent molecular weights of 35 and 40 KDa, respectively. It was purified 9-fold with a yield of 0.18% and specific activity of 246 ...

  14. Polygalacturonase and ethanol production in Kluyveromyces marxianus: potential use of polygalacturonase in foodstuffs.

    Science.gov (United States)

    Serrat, Manuel; Bermúdez, Rosa C; Villa, Tomás G

    2004-04-01

    The coproduction of ethanol and polygalacturonase (PG) in a pilot-scale batch fermentor using yeast extract--glucose (YD)--and sugar beet molasses (SBM)-based media was implemented utilizing a new high-PG-producing strain of Kluyveromyces marxianus. A certain growth inhibition was observed in SBM medium, causing ethanol and PG production to be lower. Ethanol productivity and accumulation values of 1.94 g/(L x h) and 40 g/L, respectively, were attained in YD, whereas the best fermentation efficiency (95.1%) was achieved with SBM medium. Maximal PG synthesis occurred at the end of cell growth, with values of 1.08 and 0.46 U/(mg x h) for the YD and SBM media, respectively. When the cultures reached stationary phase, PG production stopped. The highest accumulation level (17 U/mL) occurred in YD medium, in agreement with previous laboratory-scale studies carried out for this strain. The potential applications of the crude enzyme preparations were evaluated with different fruit juices and vegetable slices. The enzyme was able to increase the filtration rate of orange, pear, and apple juices by twofold. Additionally, complete clarification of apple juice was readily accomplished, whereas cucumber, carrot, and banana tissues were macerated to a lesser extent. Copyright 2004 Humana Press Inc.

  15. Kinetic characteristics of polygalacturonase enzymes hydrolyzing galacturonic acid oligomers using isothermal titration calorimetry

    Science.gov (United States)

    Polygalacturonase enzymes hydrolyze the polygalacturonic acid chains found in pectin. Interest in polygalacturonase enzymes continues as they are useful in a number of industrial processes and conversely, detrimental, as they are involved in maceration of economically important crops. While a good...

  16. Computer Aided Design of Polygalacturonase II from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Ibrahim Ali Noorbatcha

    2011-12-01

    Full Text Available Pectin is a complex polysaccharide found in the cell walls of plants and consisting mainly of esterified D-galacturonic acid resides in α-(1-4 chain. In production of fruit juice, pectin contributes to fruit juice viscosity, thereby reducing the juice production and increasing the filtration time. Polygalacturonase improves the juice production process by rapid degradation of pectin. In this project we have designed a novel polygalacturonase enzyme using computer aided design approaches. The three dimension structure of polygalacturonase is first modeled on the basis of the known crystal structure. The active site in this enzyme is identified by manual and automated docking methods. Lamarckian genetic algorithm is used for automated docking and the active site is validated by comparing with existing experimental data. This is followed by in silico mutations of the enzymes and the automated docking process is repeated using the mutant enzymes. The strength of the binding of the ligands inside the active site is evaluated by computing the binding score using Potential Mean Force (PMF method. The in silico mutations R256Q and K258N are found to decrease the binding strength of the ligand at the active site, indicating lowering of enzyme activity, which is consistent with the experimental results. Hence in silico mutations can be used to design new polygalacturonase enzymes with improved enzyme activity.ABSTRAK: Pektin adalah polisakarida kompleks yang terdapat di dalam dinding sel tumbuhan dan sebahagian besarnya terdiri daripada asid D-galakturonik terester yang ditemui di dalam rantaian α-(1-4. Dalam penghasilan jus buah-buahan, pektin menyumbang dalam kepekatan jus buah-buahan, di mana ia mengurangkan penghasilan jus dan menambahkan masa penapisan. Poligalakturonase meningkatkan proses penghasilan jus dengan pemecahan pektin dengan cepat. Dalam projek ini, kami telah merangka satu enzim poligalakturonase baru dengan menggunakan pendekatan reka

  17. Properties of a polygalacturonase-inhibiting protein isolated from 'Oroblanco' grapefruit.

    Science.gov (United States)

    D'hallewin, Guy; Schirra, Mario; Powell, Ann L. T.; Greve, L. Carl; Labavitch, John M.

    2004-03-01

    Polygalacturonase inhibiting protein (PGIP) was extracted from 'Oroblanco' grapefruit type (triploid pummelo-grapefruit) albedo tissue, purified and partially characterized. Extraction was carried out at 4 degrees C with a high ionic strength extraction buffer. After dialysis and concentration by ultrafiltration the extract was chromatographed on concanavalin A-Sepharose. The PGIP activity was bound by the lectin and then eluted using 250 mM alpha-methyl mannopyranoside, resulting in a 17-fold purification of the PGIP and demonstrating its glycoprotein nature. The anion-exchange and size-exclusion chromatography steps that followed gave a PGIP that was 857-fold purified relative to the initial tissue extract, and having a 44 kDa molecular weight, as estimated by SDS-PAGE electrophoresis. PGIP inhibition activity was tested with endo-polygalacturonase (EC 3.2.1.15) produced by Penicillium italicum and Botrytis cinerea. The radial diffusion and reducing sugar assays showed that P. italicum and B. cinerea endo-PGs were affected by PGIP, whereas no endo-PG activity was detected in the culture filtrate of P. digitatum. In vitro tests revealed that PGIP inhibited P. italicum and B. cinerea growth. By contrast, the influence of PGIP on P. digitatum, growth was negligible, perhaps because this fungus does not produce endo-PG. Following heating for 10 min at 65 degrees C the inhibitory activity of PGIP was reduced by 43%. PGIP activity decreased further as heating temperature increased, and was completely suppressed after heating at 100 degrees C for 10 min.

  18. Glycan analysis of recombinant Aspergillus niger endo-polygalacturonase A.

    Science.gov (United States)

    Woosley, Bryan D; Kim, Young Hwan; Kumar Kolli, V S; Wells, Lance; King, Dan; Poe, Ryan; Orlando, Ron; Bergmann, Carl

    2006-10-16

    The enzyme endo-polygalacturonase A, or PGA, is produced by the fungus, Aspergillus niger, and appears to play a critical role during invasion of plant cell walls. The enzyme has been homologously overexpressed in order to provide sufficient quantities of purified enzyme for structural and biological studies. We have characterized this enzyme in terms of its post-translational modifications (PTMs) and found it to be both N- and O-glycosylated. Additionally, we have characterized the glycosyl moieties using MALDI-TOF and LC-ESI mass spectrometry. The characterization of all PTMs on PGA, along with molecular modeling, allows us to reveal potential roles played by the glycans in modulating the interaction of the enzyme with other macromolecules.

  19. Polygalacturonase from Sitophilus oryzae: Possible horizontal transfer of a pectinase gene from fungi to weevils

    Directory of Open Access Journals (Sweden)

    Zhicheng Shen

    2003-08-01

    Full Text Available Endo-polygalacturonase, one of the group of enzymes known collectively as pectinases, is widely distributed in bacteria, plants and fungi. The enzyme has also been found in several weevil species and a few other insects, such as aphids, but not in Drosophila melanogaster, Anopheles gambiae, or Caenorhabditis elegans or, as far as is known, in any more primitive animal species. What, then, is the genetic origin of the polygalacturonases in weevils? Since some weevil species harbor symbiotic microorganisms, it has been suggested, reasonably, that the symbionts' genomes of both aphids and weevils, rather than the insects' genomes, could encode polygalacturonase. We report here the cloning of a cDNA that encodes endo-polygalacturonase in the rice weevil, Sitophilus oryzae (L., and investigations based on the cloned cDNA. Our results, which include analysis of genes in antibiotic-treated rice weevils, indicate that the enzyme is, in fact, encoded by the insect genome. Given the apparent absence of the gene in much of the rest of the animal kingdom, it is therefore likely that the rice weevil polygalacturonase gene was incorporated into the weevil's genome by horizontal transfer, possibly from a fungus.

  20. POLYGALACTURONASE INVOLVED IN EXPANSION1 functions in cell elongation and flower development in Arabidopsis.

    Science.gov (United States)

    Xiao, Chaowen; Somerville, Chris; Anderson, Charles T

    2014-03-01

    Pectins are acidic carbohydrates that comprise a significant fraction of the primary walls of eudicotyledonous plant cells. They influence wall porosity and extensibility, thus controlling cell and organ growth during plant development. The regulated degradation of pectins is required for many cell separation events in plants, but the role of pectin degradation in cell expansion is poorly defined. Using an activation tag screen designed to isolate genes involved in wall expansion, we identified a gene encoding a putative polygalacturonase that, when overexpressed, resulted in enhanced hypocotyl elongation in etiolated Arabidopsis thaliana seedlings. We named this gene POLYGALACTURONASE INVOLVED IN EXPANSION1 (PGX1). Plants lacking PGX1 display reduced hypocotyl elongation that is complemented by transgenic PGX1 expression. PGX1 is expressed in expanding tissues throughout development, including seedlings, roots, leaves, and flowers. PGX1-GFP (green fluorescent protein) localizes to the apoplast, and heterologously expressed PGX1 displays in vitro polygalacturonase activity, supporting a function for this protein in apoplastic pectin degradation. Plants either overexpressing or lacking PGX1 display alterations in total polygalacturonase activity, pectin molecular mass, and wall composition and also display higher proportions of flowers with extra petals, suggesting PGX1's involvement in floral organ patterning. These results reveal new roles for polygalacturonases in plant development.

  1. Insights into the Activity and Substrate Binding of Xylella fastidiosa Polygalacturonase by Modification of a Unique QMK Amino Acid Motif Using Protein Chimeras.

    Science.gov (United States)

    Warren, Jeremy G; Lincoln, James E; Kirkpatrick, Bruce C

    2015-01-01

    Polygalacturonases (EC 3.2.1.15) catalyze the random hydrolysis of 1, 4-alpha-D-galactosiduronic linkages in pectate and other galacturonans. Xylella fastidiosa possesses a single polygalacturonase gene, pglA (PD1485), and X. fastidiosa mutants deficient in the production of polygalacturonase are non-pathogenic and show a compromised ability to systemically infect grapevines. These results suggested that grapevines expressing sufficient amounts of an inhibitor of X. fastidiosa polygalacturonase might be protected from disease. Previous work in our laboratory and others have tried without success to produce soluble active X. fastidiosa polygalacturonase for use in inhibition assays. In this study, we created two enzymatically active X. fastidiosa / A. vitis polygalacturonase chimeras, AX1A and AX2A to explore the functionality of X. fastidiosa polygalacturonase in vitro. The AX1A chimera was constructed to specifically test if recombinant chimeric protein, produced in Escherichia coli, is soluble and if the X. fastidiosa polygalacturonase catalytic amino acids are able to hydrolyze polygalacturonic acid. The AX2A chimera was constructed to evaluate the ability of a unique QMK motif of X. fastidiosa polygalacturonase, most polygalacturonases have a R(I/L)K motif, to bind to and allow the hydrolysis of polygalacturonic acid. Furthermore, the AX2A chimera was also used to explore what effect modification of the QMK motif of X. fastidiosa polygalacturonase to a conserved RIK motif has on enzymatic activity. These experiments showed that both the AX1A and AX2A polygalacturonase chimeras were soluble and able to hydrolyze the polygalacturonic acid substrate. Additionally, the modification of the QMK motif to the conserved RIK motif eliminated hydrolytic activity, suggesting that the QMK motif is important for the activity of X. fastidiosa polygalacturonase. This result suggests X. fastidiosa polygalacturonase may preferentially hydrolyze a different pectic substrate or

  2. Molecular Characterization and Expression Profiles of Polygalacturonase Genes in Apolygus lucorum (Hemiptera: Miridae.

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    Full Text Available Polygalacturonase (PG is an enzyme in the salivary glands of piercing-sucking mirid bugs (Hemiptera: Miridae that plays a key role in plant feeding and injury. By constructing a full-length cDNA library, we cloned and characterized 14 PG genes from the salivary glands of Apolygus lucorum, a pestiferous mirid bug in cotton, fruit trees and other crops in China. BLAST search analysis showed that the amino acid sequences deduced from transcripts of the PG genes were closely related to PGs from other mirid bugs. Phylogenetic analysis showed that the PGs of mirid bugs had six main branches, PG1-PG6 (Genbank accession numbers: KF881899~KF881912. We investigated the mRNA expression patterns of the A. lucorum PG genes using real-time PCR. All 14 PGs were expressed significantly higher in the salivary glands than in other tissues (head, thorax, abdomen, leg and wing. For eggs and nymphs, the expression levels of these PGs were much higher in the 5th instar stage than in the egg, and 1st and 3rd instar stages. The PG expression levels in 1-day-old adults were very low, and increased in 5, 20 and 30-day-old adults. Additionally, PG expression levels were generally similar between males and females. The possible physiological functions of PGs in A. lucorum were discussed.

  3. Influence of Mode of Fermentation on Production of Polygalacturonase by a Novel Strain of Streptomyces lydicus

    Directory of Open Access Journals (Sweden)

    Nicemol Jacob

    2006-01-01

    Full Text Available Production of different pectinolytic enzymes was attempted using the actinomycete strain Streptomyces lydicus in submerged fermentation. Polygalacturonase and pectin lyase activities were detected in the culture supernatant, but the strain was not able to produce pectin esterase. Polygalacturonase production was studied in submerged, slurry-state and solid-state fermentation systems. All the experiments were carried out under static and shaking conditions. Solid-state fermentation under static condition was found to be promising. Various agroindustrial residues were tried as substrates for solid-state fermentation. Wheat bran was proved to be the best substrate.

  4. Polygalacturonase gene pgxB in Aspergillus niger is a virulence factor in apple fruit.

    Science.gov (United States)

    Liu, Cheng-Qian; Hu, Kang-Di; Li, Ting-Ting; Yang, Ying; Yang, Feng; Li, Yan-Hong; Liu, He-Ping; Chen, Xiao-Yan; Zhang, Hua

    2017-01-01

    Aspergillus niger, a saprophytic fungus, is widely distributed in soil, air and cereals, and can cause postharvest diseases in fruit. Polygalacturonase (PG) is one of the main enzymes in fungal pathogens to degrade plant cell wall. To evaluate whether the deletion of an exo-polygalacturonase gene pgxB would influence fungal pathogenicity to fruit, pgxB gene was deleted in Aspergillus niger MA 70.15 (wild type) via homologous recombination. The ΔpgxB mutant showed similar growth behavior compared with the wild type. Pectin medium induced significant higher expression of all pectinase genes in both wild type and ΔpgxB in comparison to potato dextrose agar medium. However, the ΔpgxB mutant was less virulent on apple fruits as the necrosis diameter caused by ΔpgxB mutant was significantly smaller than that of wild type. Results of quantitive-PCR showed that, in the process of infection in apple fruit, gene expressions of polygalacturonase genes pgaI, pgaII, pgaA, pgaC, pgaD and pgaE were enhanced in ΔpgxB mutant in comparison to wild type. These results prove that, despite the increased gene expression of other polygalacturonase genes in ΔpgxB mutant, the lack of pgxB gene significantly reduced the virulence of A. niger on apple fruit, suggesting that pgxB plays an important role in the infection process on the apple fruit.

  5. Crystallization and Preliminary Crystallographic Characterization of Endo-polygalacturonase II from Aspergillus niger

    NARCIS (Netherlands)

    Schröter, K.-H.; Arkema, A.; Kester, H.C.M.; Visser, J.; Dijkstra, B.W.

    1994-01-01

    The endo-polygalacturonase II from Aspergillus niger has been crystallized from an ammonium sulfate solution by the hanging drop method. The crystals belong to the monoclinic space group P2(1), with cell dimensions a = 60.6 Angstrom, b = 152.6 Angstrom, c = 74.0 Angstrom and beta = 91.2 degrees with

  6. Subsite binding energies of an exo-polygalacturonase using isothermal titration calorimetry

    Science.gov (United States)

    Thermodynamic parameters for binding of a series of galacturonic acid oligomers to an exo-polygalacturonase, RPG16 from Rhizopus oryzae, were determined by isothermal titration calorimetry. Binding of oligomers varying in chain length from two to five galacturonic acid residues is an exothermic proc...

  7. Molecular and Functional Characterization of a Polygalacturonase-Inhibiting Protein from Cynanchum komarovii That Confers Fungal Resistance in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Nana Liu

    Full Text Available Compliance with ethical standards: This study did not involve human participants and animals, and the plant of interest is not an endangered species. Polygalacturonase-inhibiting proteins (PGIPs are leucine-rich repeat proteins that plants produce against polygalacturonase, a key virulence agent in pathogens. In this paper, we cloned and purified CkPGIP1, a gene product from Cynanchum komarovii that effectively inhibits polygalacturonases from Botrytis cinerea and Rhizoctonia solani. We found the expression of CkPGIP1 to be induced in response to salicylic acid, wounding, and infection with B. cinerea and R. solani. In addition, transgenic overexpression in Arabidopsis enhanced resistance against B. cinerea. Furthermore, CkPGIP1 obtained from transgenic Arabidopsis inhibited the activity of B. cinerea and R. solani polygalacturonases by 62.7-66.4% and 56.5-60.2%, respectively. Docking studies indicated that the protein interacts strongly with the B1-sheet at the N-terminus of the B. cinerea polygalacturonase, and with the C-terminus of the polygalacturonase from R. solani. This study highlights the significance of CkPGIP1 in plant disease resistance, and its possible application to manage fungal pathogens.

  8. Application of decolourized and partially purified polygalacturonase and α-amylase in apple juice clarification

    Directory of Open Access Journals (Sweden)

    Tapati Bhanja Dey

    2014-01-01

    Full Text Available Polygalacturonase and α-amylase play vital role in fruit juice industry. In the present study, polygalacturonase was produced by Aspergillus awamori Nakazawa MTCC 6652 utilizing apple pomace and mosambi orange (Citrus sinensis var mosambi peels as solid substrate whereas, α-amylase was produced from A. oryzae (IFO-30103 using wheat bran by solid state fermentation (SSF process. These carbohydrases were decolourized and purified 8.6-fold, 34.8-fold and 3.5-fold, respectively by activated charcoal powder in a single step with 65.1%, 69.8% and 60% recoveries, respectively. Apple juice was clarified by these decolourized and partially purified enzymes. In presence of 1% polygalacturonase from mosambi peels (9.87 U/mL and 0.4% α-amylase (899 U/mL, maximum clarity (%T660nm = 97.0% of juice was attained after 2 h of incubation at 50 ºC in presence of 10 mM CaCl2. Total phenolic content of juice was reduced by 19.8% after clarification, yet with slightly higher %DPPH radical scavenging property.

  9. Application of decolourized and partially purified polygalacturonase and α-amylase in apple juice clarification.

    Science.gov (United States)

    Dey, Tapati Bhanja; Banerjee, Rintu

    2014-01-01

    Polygalacturonase and α-amylase play vital role in fruit juice industry. In the present study, polygalacturonase was produced by Aspergillus awamori Nakazawa MTCC 6652 utilizing apple pomace and mosambi orange (Citrus sinensis var mosambi) peels as solid substrate whereas, α-amylase was produced from A. oryzae (IFO-30103) using wheat bran by solid state fermentation (SSF) process. These carbohydrases were decolourized and purified 8.6-fold, 34.8-fold and 3.5-fold, respectively by activated charcoal powder in a single step with 65.1%, 69.8% and 60% recoveries, respectively. Apple juice was clarified by these decolourized and partially purified enzymes. In presence of 1% polygalacturonase from mosambi peels (9.87 U/mL) and 0.4% α-amylase (899 U/mL), maximum clarity (%T(660 nm) = 97.0%) of juice was attained after 2 h of incubation at 50 °C in presence of 10 mM CaCl2. Total phenolic content of juice was reduced by 19.8% after clarification, yet with slightly higher %DPPH radical scavenging property.

  10. Polygalacturonase production by AR2 pectinolytic bacteria through submerged fermentation of raja nangka banana peel (Musa paradisiaca var. formatypica) with variation of carbon source and pectin

    Science.gov (United States)

    Utami, R.; Widowati, E.; Ivenaria, A.; Mahajoeno, E.

    2017-04-01

    Polygalacturonase (EC 3.1.2.15) catalyzes the hydrolysis of α-1,4-glycosidic bonds on galacturonic acid. Polygalacturonase can be produced from AR2 pectinolytic bacteria isolated from orange peel and vegetable waste. Commonly cost production of enzymes were high. However, with the advancement of technology, enzymes can now be manufactured at a low cost. Production of enzymes in low cost media with agro-industrial waste is interesting. Raja nangka banana peel is agro-industrial waste that is uneconomic. Therefore, this material can be used as a pectin source in polygalacturonase production. Polygalacturonase was produced by AR2 pectinolytic bacteria with the addition of various carbon sources (1% glucose, 1% galactose, 1% lactose) and variation of pectin concentrations (5%; 7.5%; 10%). This study used submerged fermentation with a cultivation temperature of 55°C and an agitation speed of 144 rpm for a 48-h incubation time. The results showed that variation of carbon sources and pectin concentrations affected the production of polygalacturonase. After 48 h fermentation, the results showed that the number of cells of samples ranged from 8.3 to 9.445 log cells/mL; the used pectin of samples ranged from 87.170-93.745%; and the polygalacturonase activity of samples ranged from 0.030 to 0.151 U/mL. The highest polygalacturonase activity was obtained by production of polygalacturonase on 1% glucose and 10% pectin medium.

  11. Influence of carbon source, pH, and temperature on the polygalacturonase activity of Kluyveromyces marxianus CCMB 322

    Directory of Open Access Journals (Sweden)

    Rodrigo de Queiroz Oliveira

    2012-09-01

    Full Text Available Microbial pectinolytic enzymes are known to play a commercially important role in a number of industrial processes. Two kinds of yeast can be discerned regarding the production of enzymes. One group includes those which can produce enzymes in the absence of an inducer, and the other group comprises the yeasts that produce enzymes in the presence of an inducer. The objective of this study was to investigate the influence of pectic substances, glucose, pH, and temperature on the polygalacturonase activity by Kluyveromyces marxianus CCMB 322. The yeast was grown in a fermentation broth containing different concentrations of glucose and pectic substances. The polygalacturonase activity was determined by the DNS method, and the pH and temperature were optimized using a central composite experimental design. The polygalacturonase secreted by K. marxianus CCMB 322 was partially constitutive showing optimum pH and temperature of 7.36 and 70 °C, respectively, and maintained approximately 93% of its original activity for 50 minutes at 50 °C. Thermal stability of the polygalacturonase enzyme was studied at different temperatures (50, 60, 70, and 80 °C and different incubation times (0, 10, 20, 30, 40, and 50 minutes. This study showed that glucose can influence the regulation of the synthesis of polygalacturonase.

  12. In silico analysis of the polygalacturonase inhibiting protein 1 from apple, Malus domestica.

    Science.gov (United States)

    Matsaunyane, Lerato Bt; Oelofse, Dean; Dubery, Ian A

    2015-03-11

    The Malus domestica polygalacturonase inhibiting protein 1 (MdPGIP1) gene, encoding the M. domestica polygalacturonase inhibiting protein 1 (MdPGIP1), was isolated from the Granny Smith apple cultivar (GenBank accession no. DQ185063). The gene was used to transform tobacco and potato for enhanced resistance against fungal diseases. Analysis of the MdPGIP1 nucleotide sequence revealed that the gene comprises 993 nucleotides that encode a 330 amino acid polypeptide. In silico characterization of the MdPGIP1 polypeptide revealed domains typical of PGIP proteins, which include a 24 amino acid putative signal peptide, a potential cleavage site [Alanine-Leucine-Serine (ALS)] for the signal peptide, a 238 amino acid leucine-rich repeat (LRR) domain, a 46 amino acid N-terminal domain and a 22 amino acid C-terminal domain. The hydropathic evaluation of MdPGIP1 indicated a repetitive hydrophobic motif in the LRR domain and a hydrophilic surface area consistent with a globular protein. The typical consensus glycosylation sequence of Asn-X-Ser/Thr was identified in MdPGIP1, indicating potential N-linked glycosylation of MdPGIP1. The molecular mass of non-glycosylated MdPGIP1 was calculated as 36.615 kDa and the theoretical isoelectric point as 6.98. Furthermore, the secondary and tertiary structure of MdPGIP1 was modelled, and revealed that MdPGIP1 is a curved and elongated molecule that contains sheet B1, sheet B2 and 310-helices on its LRR domain. The overall properties of the MdPGIP1 protein is similar to that of the prototypical Phaseolus vulgaris PGIP 2 (PvPGIP2), and the detected differences supported its use in biotechnological applications as an inhibitor of targeted fungal polygalacturonases (PGs).

  13. Production, characterization, and identification using proteomic tools of a polygalacturonase from Fusarium graminearum.

    Science.gov (United States)

    Ortega, Leonel M; Kikot, Gisele E; Rojas, Natalia L; López, Laura M I; Astoreca, Andrea L; Alconada, Teresa M

    2014-07-01

    Since enzymatic degradation is a mechanism or component of the aggressiveness of a pathogen, enzymatic activities from a Fusarium graminearum isolate obtained from infected wheat spikes of Argentina Pampa region were studied in order to understand the disease progression, tending to help disease control. In particular, the significance of the study of polygalacturonase activity is based on that such activity is produced in the early stages of infection on the host, suggesting a crucial role in the establishment of disease. In this sense, polygalacturonase activity produced by this microorganism has been purified 375 times from 2-day-old culture filtrates by gel filtration and ion-exchange chromatography successively. The purified sample showed two protein bands in sodium dodecyl sulfate-polyacrylamide gels, with a molecular mass of 40 and 55 kDa. The protein bands were identified as an endopolygalacturonase and as a serine carboxypeptidase of F. graminearum, respectively, by peptide mass fingerprinting (matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF/TOF) fragment ion analysis). The pattern of substrate degradation analyzed by thin layer chromatography confirmed the mode of action of the enzyme as an endopolygalacturonase. High activity of the polygalacturonase against polygalacturonic acid was observed between 4 and 6 of pH, and between 30 and 50 °C, being 5 and 50 °C the optimum pH and temperature, respectively. The enzyme was fully stable at pH 5 for 120 min and 30 °C and sensible to the presence of some metal ions. This information would contribute to understand the most favorable environmental conditions for establishment of the disease. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Production and Properties of a Thermostable, pH-Stable Exo-Polygalacturonase Using Aureobasidium pullulans Isolated from Saharan Soil of Algeria Grown on Tomato Pomace.

    Science.gov (United States)

    Bennamoun, Leila; Hiligsmann, Serge; Dakhmouche, Scheherazad; Ait-Kaki, Amel; Labbani, Fatima-Zohra Kenza; Nouadri, Tahar; Meraihi, Zahia; Turchetti, Benedetta; Buzzini, Pietro; Thonart, Philippe

    2016-10-29

    Polygalacturonase is a valuable biocatalyst for several industrial applications. Production of polygalacturonase using the Aureobasidium pullulans stain isolated from Saharan soil of Algeria was investigated. Its capacity to produce polygalacturonase was assessed under submerged culture using tomato pomace as an abundant agro-industrial substrate. Optimization of the medium components, which enhance polygalacturonase activity of the strain Aureobasidium pullulans , was achieved with the aid of response surface methodology. The composition of the optimized medium was as follows: tomato pomace 40 g/L, lactose 1.84 g/L, CaCl₂0.09 g/L and pH 5.16. Practical validation of the optimum medium provided polygalacturonase activity of 22.05 U/mL, which was 5-fold higher than in unoptimized conditions. Batch cultivation in a 20 L bioreactor performed with the optimal nutrients and conditions resulted in a high polygalacturonase content (25.75 U/mL). The enzyme showed stability over a range of temperature (5-90 °C) with an optimum temperature of 60 °C with pH 5.0, exhibiting 100% residual activity after 1h at 60 °C. This enzyme was stable at a broad pH range (5.0-10). The enzyme proved to be an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of polygalacturonic acid. Moreover, the exo-polygalacturonase was able to enhance the clarification of both apple and citrus juice. As a result, an economical polygalacturonase production process was defined and proposed using an industrial food by-product.

  15. Production and Properties of a Thermostable, pH—Stable Exo-Polygalacturonase Using Aureobasidium pullulans Isolated from Saharan Soil of Algeria Grown on Tomato Pomace

    Directory of Open Access Journals (Sweden)

    Leila Bennamoun

    2016-10-01

    Full Text Available Polygalacturonase is a valuable biocatalyst for several industrial applications. Production of polygalacturonase using the Aureobasidium pullulans stain isolated from Saharan soil of Algeria was investigated. Its capacity to produce polygalacturonase was assessed under submerged culture using tomato pomace as an abundant agro-industrial substrate. Optimization of the medium components, which enhance polygalacturonase activity of the strain Aureobasidium pullulans, was achieved with the aid of response surface methodology. The composition of the optimized medium was as follows: tomato pomace 40 g/L, lactose 1.84 g/L, CaCl20.09 g/L and pH 5.16. Practical validation of the optimum medium provided polygalacturonase activity of 22.05 U/mL, which was 5-fold higher than in unoptimized conditions. Batch cultivation in a 20 L bioreactor performed with the optimal nutrients and conditions resulted in a high polygalacturonase content (25.75 U/mL. The enzyme showed stability over a range of temperature (5–90 °C with an optimum temperature of 60 °C with pH 5.0, exhibiting 100% residual activity after 1h at 60 °C. This enzyme was stable at a broad pH range (5.0–10. The enzyme proved to be an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of polygalacturonic acid. Moreover, the exo-polygalacturonase was able to enhance the clarification of both apple and citrus juice. As a result, an economical polygalacturonase production process was defined and proposed using an industrial food by-product.

  16. Production, Purification, and Characterization of Polygalacturonase from Mucor circinelloides ITCC 6025

    Directory of Open Access Journals (Sweden)

    Akhilesh Thakur

    2010-01-01

    Full Text Available Mucor circinelloides produced an extracellular polygalacturonase enzyme, the production of which was enhanced when various production parameters were optimized. Maximum polygalacturonase (PGase activity was obtained in 48 h at 30∘C and pH 4.0 with pectin methyl ester (1% w/v as carbon source and a combination of casein hydrolysate (0.1% w/v and yeast extract (0.1% w/v as nitrogen source. The enzyme was purified to homogeneity (13.3-fold by Sephacryl S-100 gel-filtration chromatography. Its molecular weight was 66 kDa on SDS-PAGE. The enzyme was found to have Km and Vmax values of 2.2 mM and 4.81 IU/ml at 0.1% to 0.5% (w/v concentration of the substrate. The addition of phenolic acids (0.05 mM, metal ions such as Mn+2, Co+2, Mg+2, Fe+3, Al+3, Hg+2, and Cu+2, and thiols had inhibitory effect on the enzyme. The enzyme showed maximum activity in the presence of polygalacturonic acid (0.1% w/v at pH 5.5 and 42∘C.

  17. Isolation of a yeast strain able to produce a polygalacturonase with maceration activity of cassava roots

    Directory of Open Access Journals (Sweden)

    María Alicia Martos

    2013-06-01

    Full Text Available The objective of the present study was the isolation of a yeast strain, from citrus fruit peels, able to produce a polygalacturonase by submerged fermentation with maceration activity of raw cassava roots. Among 160 yeast strains isolated from citrus peels, one strain exhibited the strongest pectinolytic activity. This yeast was identified as Wickerhamomyces anomalus by 5.8S-ITS RFLP analysis and confirmed by amplification of the nucleotide sequence. The yeast produced a polygalacturonase (PG in Erlenmeyer shake flasks containing YNB, glucose, and citrus pectin. PG synthesis occurred during exponential growth phase, reaching 51 UE.mL-1 after 8 hours of fermentation. A growth yield (Yx/s of 0.43 gram of cell dry weight per gram of glucose consumed was obtained, and a maximal specific growth rate (µm of 0.346 h-1 was calculated. The microorganism was unable to assimilate sucrose, galacturonic acid, polygalacturonic acid, or citrus pectin, but it required glucose as carbon and energy source and polygalacturonic acid or citrus pectin as inducers of enzyme synthesis. The crude enzymatic extract of Wickerhamomyces anomalus showed macerating activity of raw cassava. This property is very important in the production of dehydrated mashed cassava, a product of regional interest in the province of Misiones, Argentina.

  18. Sugar-cane juice induces pectin lyase and polygalacturonase in Penicillium griseoroseum

    Directory of Open Access Journals (Sweden)

    Minussi Rosana Cristina

    1998-01-01

    Full Text Available The use of other inducers as substitutes for pectin was studied aiming to reduce the production costs of pectic enzymes. The effects of sugar-cane juice on the production of pectin lyase (PL and polygalacturonase (PG by Penicillium griseoroseum were investigated. The fungus was cultured in a mineral medium (pH 6.3 in a rotary shaker (150 rpm for 48 h at 25oC. Culture media were supplemented with yeast extract and sucrose or sugar-cane juice. Sugar-cane juice added singly to the medium promoted higher PL activity and mycelial dry weight when compared to pectin and the use of sugar-cane juice and yeast extract yielded levels of PG activity that were similar to those obtained with sucrose-yeast extract or pectin. The results indicated that, even at low concentrations, sugar-cane juice was capable of inducing pectin lyase and polygalacturonase with no cellulase activity in P. griseoroseum.

  19. Kinetic properties of two Rhizopus exo-polygalacturonase enzymes hydrolyzing galacturonic acid oligomers using isothermal titration calorimetry

    Science.gov (United States)

    The kinetic characteristics of two Rhizopus oryzae exo-polygalacturonases acting on galacturonic acid oligomers (GalpA) were determined using isothermal titration calorimetry (ITC). RPG15 hydrolyzing (GalpA)2 demonstrated a Km of 55 uM and kcat of 10.3 s^-1^ while RPG16 was shown to have greater af...

  20. Cloning and expression of Pectobacterium carotovorum endo-polygalacturonase gene in Pichia pastoris for production of oligogalacturonates

    Science.gov (United States)

    A bacterial endo-polygalacturonase (endo-PGase) gene from the plant pathogen Pectobacterium carotovorum was cloned into pGAPZaA vector and constitutively expressed in Pichia pastoris. The recombinant endo-PGase secreted by the Pichia clone showed a 1.7 fold increase when the culture medium included ...

  1. Neosartorya glabra polygalacturonase produced from fruit peels as inducers has the potential for application in passion fruit and apple juices

    Directory of Open Access Journals (Sweden)

    Vanessa Elisa Pinheiro

    2017-04-01

    Full Text Available Summary Polygalacturonases are enzymes with the biotechnological potential for use in fruit juice clarification and for the enhancement of filtration efficiency. The aim of this work was to assess the production of polygalacturonase by the fungus Neosartorya glabra by means of solid-state and submerged fermentation using fruit peel residues as the carbon source, and also apply the enzyme in the clarification and decrease in viscosity of passion fruit and apple juices. The highest polygalacturonase (4.52 U/g/h production was obtained by means of submerged fermentation in Vogel´s medium (1964 containing orange peel – Bahia variety (Citrus sinensis, at a concentration of 1.5% (w/v, dried mass at 30-35°C for 72 h. The polygalacturonase of the crude extract presented optimal activity at 60°C and pH 5.5. The enzyme retained around 90% of the initial activity after 180 minutes at 40°C, and 50% of the initial activity after 150 minutes at 50°C. The enzyme was shown to be stable at acid pH values (3.0-6.5 after 120 minutes at 25oC. All these favourable enzymatic properties make the polygalacturonase attractive for potential uses in the industry of pectin-rich fruit juices, since the application of the crude extract to passion fruit (Passiflora edulis juice caused an 80% reduction in viscosity and 75% decrease in light absorbance. In the processing of apple pulp juice (Malus domestica, there was a 50% reduction in viscosity and 78% decrease in light absorbance.

  2. Toward Enhancing the Enzymatic Activity of a Novel Fungal Polygalacturonase for Food Industry: Optimization and Biochemical Analyses.

    Science.gov (United States)

    Shetaia, Yousseria M H; El-Baz, Ashraf F; ElMekawy, Ahmed M

    2017-08-11

    The review of literature and patents shows that enhancing the PG production and activity are still required to fulfill the increasing demands. A dual optimization process, which involved Plackett-Burman design (PBD), with seven factors, and response surface methodology, was applied to optimize the production of extracellular polygalacturonase (PG) enzyme produced by a novel strain of Aspergillus flavus isolated from rotten orange fruit. The fungal PG was purified and biochemically characterized. Three variables (harvesting time, pH and orange pomace concentration), that were verified to be significant by the PBD analysis, were comprehensively optimized via Box-Behnken design. According to this optimization, the highest PG activity (4073 U/mL) was obtained under pH 7 after 48 h using 40 g/L orange pomace as a substrate, with enhancement in PG activity by 51% compared to the first PBD optimization step. The specific activity of the purified PG was 1608 U/mg with polygalacturonic acid and its molecular weight was 55 kDa. The optimum pH was 5 with relative thermal stability (80%) at 50˚C after 30 min. The PG activity improved in the presence of Cu2+ and Ca2+, while Ba2+, Fe2+ and Zn2+ greatly inhibited the enzyme activity. The obvious Km and Vmax values were 0.8 mg/mL and 2000 µmol/min, respectively. This study is a starting point for initial research in the field of optimization and characterization of A. flavus PG. The statistical optimization of A. flavus PG and its biochemical characterization clearly revealed that this fungal strain can be a potential producer of PG which has a wide range of industrial applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Screening of bacterial strains for pectinolytic activity: characterization of the polygalacturonase produced by Bacillus sp

    Directory of Open Access Journals (Sweden)

    Soares Márcia M.C.N.

    1999-01-01

    Full Text Available One hundred sixty eight bacterial strains, isolated from soil and samples of vegetable in decomposition, were screened for the use of citrus pectin as the sole carbon source. 102 were positive for pectinase depolymerization in assay plates as evidenced by clear hydrolization halos. Among them, 30% presented considerable pectinolytic activity. The cultivation of these strains by submerged and semi-solid fermentation for polygalacturonase production indicated that five strains of Bacillus sp produced high quantities of the enzyme. The physico-chemical characteristics, such as optimum pH of 6.0 - 7.0, optimum temperatures between 45oC and 55oC, stability at temperatures above 40oC and in neutral and alkaline pH, were determined.

  4. Xylella fastidiosa requires polygalacturonase for colonization and pathogenicity in Vitis vinifera grapevines.

    Science.gov (United States)

    Roper, M Caroline; Greve, L Carl; Warren, Jeremy G; Labavitch, John M; Kirkpatrick, Bruce C

    2007-04-01

    Xylella fastidiosa is the causal agent of Pierce's disease of grape, an economically significant disease for the grape industry. X. fastidiosa systemically colonizes the xylem elements of grapevines and is able to breach the pit pore membranes separating xylem vessels by unknown mechanisms. We hypothesized that X. fastidiosa utilizes cell wall degrading enzymes to break down pit membranes, based on the presence of genes involved in plant cell wall degradation in the X. fastidiosa genome. These genes include several beta-1,4 endoglucanases, several xylanases, several xylosidases, and one polygalacturonase (PG). In this study, we demonstrated that the pglA gene encodes a functional PG. A mutant in pglA lost pathogenicity and was compromised in its ability to systemically colonize Vitis vinifera grapevines. The results indicate that PG is required for X. fastidiosa to successfully infect grapevines and is a critical virulence factor for X. fastidiosa pathogenesis in grapevine.

  5. Crystallization, X-ray diffraction analysis and preliminary structure determination of the polygalacturonase PehA from Agrobacterium vitis

    International Nuclear Information System (INIS)

    Vordtriede, Paul B.; Yoder, Marilyn D.

    2008-01-01

    The acidic polygalacturonase PehA from A. vitis has been crystallized. A molecular-replacement solution indicated a right-handed parallel β-helix fold. Polygalacturonases are pectate-degrading enzymes that belong to glycoside hydrolase family 28 and hydrolyze the α-1,4 glycosidic bond between neighboring galacturonasyl residues of the homogalacturonan substrate. The acidic polygalacturonase PehA from Agrobacterium vitis was overexpressed in Escherichia coli, where it accumulated in the periplasmic fraction. It was purified to homogeneity via a two-step chromatography procedure and crystallized using the hanging-drop vapour-diffusion technique. PehA crystals belonged to space group P2 1 , with unit-cell parameters a = 52.387, b = 62.738, c = 149.165 Å, β = 89.98°. Crystals diffracted to 1.59 Å resolution and contained two molecules per asymmetric unit. An initial structure determination by molecular replacement indicated a right-handed parallel β-helix fold

  6. Polygalacturonase inhibitor protein from fruits of anthracnose resistant and susceptible varieties of Chilli (Capsicum annuum L).

    Science.gov (United States)

    Shivashankar, S; Thimmareddy, C; Roy, Tapas K

    2010-08-01

    Chilli fruit is highly susceptible to anthracnose infection at the stage of harvest maturity, due to which the fruit yield in the leading commercial variety Byadgi is severely affected. Field studies on screening of several varieties for resistance to anthracnose have shown that a variety of chilli AR-4/99K is resistant to anthracnose infection. In many crops, resistance to fungal attack has been correlated with PGIP activity in developing fruits based on which transgenic varieties have been developed with resistance to fungi. The present study was carried out to determine whether anthracnose resistance in AR-4/99K was due to the increased levels of PGIP alone and/ or due to differences, if any, in the properties of PGIP. Hence, a comparative study of the properties of polygalacturonase inhibitor protein (PGIP) isolated from fruits of anthracnose resistant chilli var AR-4/99K and a susceptible variety Byadgi was conducted with the objective of utilizing the information in genetic transformation studies. Both the PGIPs from anthracnose resistant and susceptible varieties of chilli exhibited similarities in the elution pattern on Sephadex gel, DEAE cellulose, PAGE and SDS-PAGE. The two PGIPs were active over a wide range of pH and temperature. Both PGIPs showed differential inhibitory activity against polygalacturonase (PG) secreted by Colletotrichum gleosporoides, C. capsici, C. lindemuthianum, Fusarium moniliforme and Sclerotium rolfsii. The inhibitory activity of PGIP from both resistant and susceptible varieties was the highest (82% and 76%, respectively) against the PG from Colletotrichum capsici, a pathogen causing anthracnose rot of chilli, while the activity was lower (1.27 to 12.3%) on the other fungal PGs. Although PGIP activity decreased with fruit maturation in both the varieties, the resistant variety maintained a higher activity at 45 days after flowering (DAF) as compared to the susceptible variety which helped it to overcome the infection by

  7. Simultaneous Production of Amyloglucosidase and Exo-Polygalacturonase by Aspergillus niger in a Rotating Drum Reactor.

    Science.gov (United States)

    Colla, Eliane; Santos, Lucielen Oliveira; Deamici, Kricelle; Magagnin, Glênio; Vendruscolo, Mauricio; Costa, Jorge Alberto Vieira

    2017-02-01

    Simultaneous production of amyloglucosidase (AMG) and exo-polygalacturonase (exo-PG) was carried out by Aspergillus niger in substrate of defatted rice bran in a rotating drum bioreactor (RDB) and studied by a 3 1  × 2 2 factorial experimental design. Variables under study were A. niger strains (A. niger NRRL 3122 and A. niger t0005/007-2), types of inoculum (spore suspension and fermented bran), and types of inducer (starch, pectin, and a mix of both). Solid-state fermentation process (SSF) was conducted at 30 °C under 60-vvm aeration for 96 h in a pilot scale. Production of AMG and exo-PG was significantly affected by the fungal strain and the type of inoculum, but inducers did not trigger any significant effect, an evidence of the fact that these enzymes are constitutive. The maximum activity of exo-PG was 84 U g dm -1 whereas the maximum yield of AMG was 886.25 U g dm -1 .

  8. Production, purification and characterization of an exo-polygalacturonase from Penicillium janthinellum sw09

    Directory of Open Access Journals (Sweden)

    YUPING MA

    2016-01-01

    Full Text Available ABSTRACT A soil isolate, Penicillium janthinellum sw09 has been found to produce significant amounts of an extracellular pectinase subsequently characterized as exo-polygalacturonase (exo-PG. By optimizing growth conditions, P. janthinellum sw09 produced high amount of exo-PG (16.54 units/mL. The crude enzyme was purified by gel filtration chromatography and two exo-PG activity peaks (designated as PGI and PGII were revealed. On SDS-PAGE analysis, purified PGII using DEAE-Sepharose FF column, was found to be a single band with a molecular mass of 66.2 kDa. The purified PGII exhibited maximal activity at the temperature of 45 oC and pH 5.0. The stability profiles show that PGII is more stable in the pH range of 4.0-8.0 and below 60 oC. The Km and Vmax for the enzyme was 1.74 mg/mL and 18.08 μmol/ (mL•min, respectively. Due to this enzymatic characterization, this pectinase is an attractive candidate for applications in degradation of pectin.

  9. Purification and partial characterization of an exo-polygalacturonase from Paecilomyces variotii liquid cultures.

    Science.gov (United States)

    de Lima Damásio, Andre Ricardo; da Silva, Tony Márcio; Maller, Alexandre; Jorge, João Atílio; Terenzi, Hector Francisco; Polizeli, Maria de Lourdes Teixeira de Moraes

    2010-03-01

    An extracellular polygalacturonase (PG) produced from Paecilomyces variotii was purified to homogeneity through two chromatography steps using DEAE-Fractogel and Sephadex G-100. The molecular weight of P. variotii PG was 77,300 Da by gel filtration and SDS-PAGE. PG had isoelectric point of 4.37 and optimum pH 4.0. PG was very stable from pH 3.0 to 6.0. The extent of hydrolysis of different pectins by the purified enzyme was decreased with an increase in the degree of esterification. PG had no activity toward non-pectic polysaccharides. The apparent K(m) and V(max) values for hydrolyzing sodium polypectate were 1.84 mg/mL and 432 micromol/min/mg, respectively. PG was found to have temperature optimum at 65 degrees Celsius and was totally stable at 45 degrees Celsius for 90 min. Half-life at 55 degrees Celsius was 50.6 min. Almost all the examined metal cations showed partial inhibitory effects under enzymatic activity, except for Na(+1), K(+1), and Co(+2) (1 mM) and Cu(+2) (1 and 10 mM).

  10. Abundance and genetic diversity of microbial polygalacturonase and pectate lyase in the sheep rumen ecosystem.

    Directory of Open Access Journals (Sweden)

    Peng Yuan

    Full Text Available Efficient degradation of pectin in the rumen is necessary for plant-based feed utilization. The objective of this study was to characterize the diversity, abundance, and functions of pectinases from microorganisms in the sheep rumen.A total of 103 unique fragments of polygalacturonase (PF00295 and pectate lyase (PF00544 and PF09492 genes were retrieved from microbial DNA in the rumen of a Small Tail Han sheep, and 66% of the sequences of these fragments had low identities (<65% with known sequences. Phylogenetic tree building separated the PF00295, PF00544, and PF09492 sequences into five, three, and three clades, respectively. Cellulolytic and noncellulolytic Butyrivibrio, Prevotella, and Fibrobacter species were the major sources of the pectinases. The two most abundant pectate lyase genes were cloned, and their protein products, expressed in Escherichia coli, were characterized. Both enzymes probably act extracellularly as their nucleotide sequences contained signal sequences, and they had optimal activities at the ruminal physiological temperature and complementary pH-dependent activity profiles.This study reveals the specificity, diversity, and abundance of pectinases in the rumen ecosystem and provides two additional ruminal pectinases for potential industrial use under physiological conditions.

  11. Detection of the genetic variation of polygalacturonase-inhibiting protein gene 2 in autotetraploid alfalfa (Medicago sativa) using an improved SSCP technique.

    Science.gov (United States)

    Gui, Z; Liu, H Q; Wang, Y; Yuan, Q H; Xin, N; Zhang, X; Li, X L; Pi, Y S; Gao, J M

    2014-12-04

    In this study, 2 approaches were adopted to obtain good single-strand conformation polymorphism (SSCP) data for autotetraploid alfalfa; primers were added to PCR products, and fluorescent-labeled primers were utilized. PCR-SSCP conditions for a 331-bp fragment in the coding region of polygalacturonase-inhibiting protein gene 2 in alfalfa (MsPGIP2) were optimized, and the results showed that the best SSCP gel pattern could be obtained when the loading mixture was made by mixing 1 μL PCR products, 0.2 to 0.8 μL unlabeled primers (50 μM) and 4 to 16 μL loading buffer. Furthermore, the use of the fluorescent-labeled primers resulted in 2 separated electrophoresis images from 2 complementary single DNA strands, thus making the determination of alleles and idiotypes a relatively easy task. In addition, the results of sequencing prove that the determination of alleles and idiotypes were accurate based on SSCP analysis. Finally, a total of 9 alleles with 18 SNP sites were identified for MsPGIP2 in the alfalfa variety 'Algonquin'. In conclusion, MsPGIP2 possessed great genetic variation, and the addition of primers to the PCR products in combination with the fluorescent labeling of primers could significantly improve the sensitivity and resolution of SSCP analysis. This technique could be used for genetic diversity detection and marker-assisted breeding of useful genes in autopolyploid species such as alfalfa.

  12. Molecular cloning and characterization of Polygalacturonase-Inhibiting Protein and Cinnamoyl-Coa Reductase genes and their association with fruit storage conditions in blueberry (Vaccinium corymbosum)

    KAUST Repository

    Khraiwesh, Basel

    2013-05-13

    Blueberry is a widely grown and easily perishable fruit crop. An efficient post-harvest handling is critical, and for that purpose gene technology methods have been part of ongoing programmes to improve crops with high food values such as blueberry. Here we report the isolation, cloning, characterization and differential expression levels of two cDNAs encoding Polygalacturonase-Inhibitor Protein (PGIP) and Cinnamoyl-Coa Reductase (CCR) from blueberry fruits in relation to various storage conditions. The open reading frame of PGIP and CCR encodes a polypeptide of 329 and 347 amino acids, respectively. To assess changes in the expression of blueberry PGIP and CCR after harvest, a storage trial was initiated. The northern blots hybridization showed a clear differential expression level of PGIP and CCR between freshly harvested and stored fruits as well as between fruits stored under various storage conditions. Although the prospects of exploiting such a strategy for crop improvement are limited, the results provide further insight into the control of the quality over the storage period at the molecular level.

  13. Molecular cloning and characterization of Polygalacturonase-Inhibiting Protein and Cinnamoyl-Coa Reductase genes and their association with fruit storage conditions in blueberry (Vaccinium corymbosum)

    KAUST Repository

    Khraiwesh, Basel; Harb, Jamil; Qudeimat, Enas

    2013-01-01

    Blueberry is a widely grown and easily perishable fruit crop. An efficient post-harvest handling is critical, and for that purpose gene technology methods have been part of ongoing programmes to improve crops with high food values such as blueberry. Here we report the isolation, cloning, characterization and differential expression levels of two cDNAs encoding Polygalacturonase-Inhibitor Protein (PGIP) and Cinnamoyl-Coa Reductase (CCR) from blueberry fruits in relation to various storage conditions. The open reading frame of PGIP and CCR encodes a polypeptide of 329 and 347 amino acids, respectively. To assess changes in the expression of blueberry PGIP and CCR after harvest, a storage trial was initiated. The northern blots hybridization showed a clear differential expression level of PGIP and CCR between freshly harvested and stored fruits as well as between fruits stored under various storage conditions. Although the prospects of exploiting such a strategy for crop improvement are limited, the results provide further insight into the control of the quality over the storage period at the molecular level.

  14. Purification and Properties of Polygalacturonase Produced by Thermophilic Fungus Thermoascus aurantiacus CBMAI-756 on Solid-State Fermentation

    Directory of Open Access Journals (Sweden)

    Eduardo da Silva Martins

    2013-01-01

    Full Text Available Polygalacturonases are enzymes involved in the degradation of pectic substances, being extensively used in food industries, textile processing, degumming of plant rough fibres, and treatment of pectic wastewaters. Polygalacturonase (PG production by thermophilic fungus Thermoascus aurantiacus on solid-state fermentation was carried out in culture media containing sugar cane bagasse and orange bagasse in proportions of 30% and 70% (w/w at 45°C for 4 days. PG obtained was purified by gel filtration and ion-exchange chromatography. The highest activity was found between pH 4.5 and 5.5, and the enzyme preserved more than 80% of its activity at pH values between 5.0 and 6.5. At pH values between 3.0 and 4.5, PG retained about 73% of the original activity, whereas at pH 10.0 it remained around 44%. The optimum temperature was 60–65°C. The enzyme was completely stable when incubated for 1 hour at 50°C. At 55°C and 60°C, the activity decreased 55% and 90%, respectively. The apparent molecular weight was 29.3 kDa, Km of 1.58 mg/mL and Vmax of 1553.1 μmol/min/mg. The presence of Zn+2, Mn+2, and Hg+2 inhibited 59%, 77%, and 100% of enzyme activity, respectively. The hydrolysis product suggests that polygalacturonase was shown to be an endo/exoenzyme.

  15. Screening and Characterization of Polygalacturonase as Potential Enzyme for Keprok Garut Orange (Citrus nobilis var. chrysocarpa) Juice Clarification

    Science.gov (United States)

    Widowati, E.; Utami, R.; Kalistyatika, K.

    2017-11-01

    Use of thermostable enzyme from bacilli for industrial application is significant. This research aimed to isolate thermophilic pectinolytic bacteria from orange peel and vegetable waste which produced thermostable polygalacturonase, to investigate the polygalacturonase ability in clarifying keprok Garut orange juice, and to characterize polygalacturonase based on pH optimum, temperature optimum, enzyme stability, enzyme kinetics KM, and Vmax. Obtained, 14 isolates that further selected to 4 best isolates based on highest polygalacturonase activity and keprok Garut orange juice clarification ability. Four selected enzyme isolates were AR 2, AR 4, KK 4, and KK 5 had ability to increase juice transmittance, decrease juice viscosity and also reduce total soluble solid. Furthermore 4 selected isolates were partially purified by ammonium sulphate precipitation and dialysis method. Four partially purified enzymes were known that enzyme character of AR 2 optimum at pH 6; AR 4 optimum at pH 5.5; KK 4 optimum at pH 6; and KK 5 optimum at pH 4.5. Four enzymes were optimum at temperature 60°C thus stable at temperature 50-60°C, this characteristic indicate that enzymes were thermostable. AR 2 showed active activity stable at pH 4-7; AR 4 showed active activity stable at pH 6-7; KK 4 showed active activity stable at pH 4-6; however KK 5 stable at pH 4-5. Enzyme AR 2 and KK 4 was getting inactive at pH 11, thus AR 4 and KK 5 inactive at pH 12. KM value of AR 2, AR 4, KK 4, and KK 5 was 0.0959; 0.0974; 0.0966; and 0.178 mg/ml respectively. Vmax of AR 2, AR 4, KK 4, and KK 5 was 0.0203; 0.0202; 0.0185; and 0.0229 U/ml respectively. Enzyme AR 2 was the most compatible enzyme to be applied in keprok Garut orange juice clarification for it had the lowest KM value.

  16. Purification, Kinetic, and Thermodynamic Characteristics of an Exo-polygalacturonase from Penicillium notatum with Industrial Perspective.

    Science.gov (United States)

    Amin, Faiza; Bhatti, Haq Nawaz; Bilal, Muhammad; Asgher, Muhammad

    2017-09-01

    An extracellular exo-polygalacturonase (exo-PG) produced by Penicillium notatum was purified (3.07-folds) by ammonium sulfate fractionation, ion exchange, and gel filtration chromatography. Two distinct isoforms of the enzyme, namely exo-PGI and exo-PGII, were identified during column purification with molecular weights of 85 and 20 kDa, respectively, on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme displayed its optimum activity at pH 6.0 and 50 °C and was found to be stable in the slightly acidic pH (ranging from 4.5 to 6.0). Michaelis-Menten parameters, i.e., K m (app) and V max for pectin hydrolysis, were calculated to be 16.6 mg/mL and 20 μmol/mL/min, respectively. The enzyme followed biphasic deactivation kinetics. Phase I of the exo-PGI showed half-lives of 6.83 and 2.39 min at 55 and 80 °C, respectively, whereas phase II of the enzyme exhibited a half-life of 63.57 and 22.72 min at 55 and 80 °C, respectively. The activation energy for denaturation was 51.66 and 44.06 kJ/mol for phase I and phase II of the exo-PGI, respectively. The enzyme activity was considerably enhanced by Mn 2+ , whereas exposure to a hydrophobic environment (urea and sodium azide solution) drastically suppressed the enzyme activity. Results suggest that exo-PGI might be considered as a potential candidate for various applications, particularly in the food and textile industries.

  17. Phylogenetics and Gene Structure Dynamics of Polygalacturonase Genes in Aspergillus and Neurospora crassa

    Directory of Open Access Journals (Sweden)

    Jin-Sung Hong

    2013-09-01

    Full Text Available Polygalacturonase (PG gene is a typical gene family present in eukaryotes. Forty-nine PGs were mined from the genomes of Neurospora crassa and five Aspergillus species. The PGs were classified into 3 clades such as clade 1 for rhamno-PGs, clade 2 for exo-PGs and clade 3 for exo- and endo-PGs, which were further grouped into 13 sub-clades based on the polypeptide sequence similarity. In gene structure analysis, a total of 124 introns were present in 44 genes and five genes lacked introns to give an average of 2.5 introns per gene. Intron phase distribution was 64.5% for phase 0, 21.8% for phase 1, and 13.7% for phase 2, respectively. The introns varied in their sequences and their lengths ranged from 20 bp to 424 bp with an average of 65.9 bp, which is approximately half the size of introns in other fungal genes. There were 29 homologous intron blocks and 26 of those were sub-clade specific. Intron losses were counted in 18 introns in which no obvious phase preference for intron loss was observed. Eighteen introns were placed at novel positions, which is considerably higher than those of plant PGs. In an evolutionary sense both intron loss and gain must have taken place for shaping the current PGs in these fungi. Together with the small intron size, low conservation of homologous intron blocks and higher number of novel introns, PGs of fungal species seem to have recently undergone highly dynamic evolution.

  18. Characteristics of exo- polygalacturonase produced by irradiated Aspergillus niger and Trichoderma viride spores

    International Nuclear Information System (INIS)

    Youssef, B.M.; Swailam, H.M.; Gomaa, N.M.; EL-Mehallawy, A.A.

    2010-01-01

    Out of 69 fungal isolates from nine pectin rich fresh fruit wastes-showed pectinolytic activity, two were the powerful and best. They were identified as Aspergillus niger and Trichoderma viride. Gamma irradiation of the spore suspensions of these two isolates (0- 3 kGy) stimulated the exo-polygalacturonase (PG) production. Treatment with 0.25 kGy and 0.25-0.50 kGy was found to be the best doses for inducing PG activity produced from T. viride and Asp. niger respectively . The enzyme characteristics were also studied. The optimum temperature of T. viride enzyme reaction was 5 C compared with 45 degree C for Asp. niger enzyme extract.The optimum incubation time of T. viride enzyme reaction was 70-80 min which greater than that of Asp. niger namely 60 min.The results of enzyme reaction ph revealed that the best PG activity was observed at ph 5.0 for the extract of the two fungal isolates. The stability of the enzyme was affected markedly by each of incubation temp., incubation period and ph value .A. niger and T. viride crude extract enzymes were stimulated with Mn 2+ while Zn 2+ and Ca 2+ were inhibitors. The best volume of crude enzyme extract was 3.00 ml in case of T. viride while in case of A. niger was 2.00 ml. T. viride enzyme extract showed its highest enzyme activity with substrate concentration 1.5 % while that of A. niger was found to be 3.0%.

  19. Efficient Expression of an Acidic Endo-polygalacturonase from Aspergillus niger and Its Application in Juice Production.

    Science.gov (United States)

    Wang, Jiaojiao; Zhang, Yuhong; Qin, Xing; Gao, Lingyu; Han, Bin; Zhang, Deqing; Li, Jinyang; Huang, He; Zhang, Wei

    2017-04-05

    An endo-polygalacturonase gene (pga-zj5a) was cloned by reverse transcription from cDNAs synthesized from Aspergillus niger ZJ5 total RNA. The open reading frame of pga-zj5a was 1089 base pairs encoding 362 amino acids. Pga-zj5a lacking a signal peptide sequence was successfully amplified using A. niger ZJ5 cDNA as the template and was ligated into the pPIC9 vector. The resulting plasmid was transformed into competent cells of Pichia pastoris GS115 for heterologous expression. The polygalacturonase showed a maximum activity level of 10436 U/mL in the culture supernatant from a 3 L fermenter. Assays of enzymatic properties showed that the optimal pH and temperature of the recombinant PGA-ZJ5A were 4.5 and 40 °C, respectively. PGA-ZJ5A was effective in pear juice clarification, increased the volume of pear juice by 41.8%, and improved its light transmittance 3-fold.

  20. Simultaneous amyloglucosidase and exo-polygalacturonase production by Aspergillus niger using solid-state fermentation

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Vieira Costa

    2007-09-01

    Full Text Available Amyloglucosidase (AMG and exo-polygalacturonase (exo-PG were simultaneously produced by two different strains of Aspergillus niger in solid-state fermentation (SSF using defatted rice-bran as substrate. The effect of Aspergillus niger strain (t0005/007-2 and/or CCT 3312, inoculum type (spore suspension or fermented bran and addition of inducers (pectin and/or starch to the culture media was studied using a 3² x 2¹ factorial experimental design. The production of AMG and exo-PG was significantly affected by fungal strain and inoculum type but inducers had no effect. The maximum yields obtained were 1310 U/g dm for AMG using a spore suspension of A. niger CCT 3312 and 50.2 U/g dm for exo-PG production, using A. niger t0005/007-2 and fermented bran as inoculum. The yields obtained represented acceptable values in comparison with data available in the literature and indicated that defatted rice-bran was a good nutrient source.As enzimas amiloglicosidase (AMG e exo-poligalacturonase (exo-PG foram produzidas simultaneamente por duas cepas de Aspergillus niger, através de fermentação em estado sólido usando farelo de arroz desengordurado como substrato. Foram avaliados os efeitos da cepa de Aspergillus niger, tipo de inóculo e adição de indutores no meio de cultura, utilizando-se um planejamento experimental fracionário 3² x 2¹. O máximo rendimento obtido foi 1310 U/g ms para a produção de AMG e 50,2 U/g ms para a exo-PG. Comparando-se estes resultados com dados da literatura pode-se dizer que os rendimentos obtidos foram aceitáveis e indicam que o farelo de arroz desengordurado é uma boa fonte de nutrientes. A produção de AMG e exo-PG foi significativamente afetada pelas variáveis cepa de A. niger e tipo de inóculo, enquanto a variável indutor não apresentou influência significativa na produção destas enzimas.

  1. Production of polygalacturonases by Aspergillus oryzae in stirred tank and internal- and external-loop airlift reactors.

    Science.gov (United States)

    Fontana, Roselei Claudete; da Silveira, Maurício Moura

    2012-11-01

    The production of endo- and exo-polygalacturonase (PG) by Aspergillus oryzae was assessed in stirred tank reactors (STRs), internal-loop airlift reactors (ILARs) and external-loop airlift reactors (ELARs). For STR production, we compared culture media formulated with either pectin (WBE) or partially hydrolyzed pectin. The highest enzyme activities were obtained in medium that contained 50% pectin in hydrolyzed form (WBE5). PG production in the three reactor types was compared for WBE5 and low salt WBE medium, with additional salts added at 48, 60 and 72h (WBES). The ELARs performed better than the ILARs in WBES medium where the exo-PG was the same concentration as for STRs and the endo-PG was 20% lower. These results indicate that PG production is higher under experimental conditions that result in higher cell growth with minimum pH values less than 3.0. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Effect of Carbon and Nitrogen Sources on Polygalacturonase Production by Trichoderma viride (BITRS-1001 Isolated from Tar Sand in Ondo State, Nigeria

    Directory of Open Access Journals (Sweden)

    Ogunmolu, F. E.

    2011-01-01

    Full Text Available The effects of the various carbon and nitrogen substrates on the growth and polygalacturonase activity of Trichoderma viride (BITRS-1001 isolated from the tar sand deposit in Gbelejuloda-Irele Ondo State, Nigeria were investigated in submerged cultivation at 30 °C ± 2 °C. The commercial carbon and nitrogen substrates included sucrose, fructose, starch, maltose, lactose and peptone, sodium nitrate, urea and casein respectively. All the carbon substrates used supported the growth of T. viride (0.566 to 0.156 g/50 mL of culture medium with starch supporting the highest biomass yield and sucrose the least biomass yield. Maximum polygalacturonase activity of 3033 U/mL was recorded in maltose medium. Maximum biomass yield on the nitrogen sources was observed in the organic nitrogen namely peptone and casein with values not significantly different from each other at p ≤ 0.05. In the determination of the crude enzyme activity on the nitrogen sources, maximum polygalacturonase activity of 12,400 U/mL was recorded in peptone medium. Hence, a careful manipulation of these nutrient substrates could help to optimise the production of this enzyme on a large scale.

  3. Identification and expression analysis of BoMF25, a novel polygalacturonase gene involved in pollen development of Brassica oleracea.

    Science.gov (United States)

    Lyu, Meiling; Liang, Ying; Yu, Youjian; Ma, Zhiming; Song, Limin; Yue, Xiaoyan; Cao, Jiashu

    2015-06-01

    BoMF25 acts on pollen wall. Polygalacturonase (PG) is a pectin-digesting enzyme involved in numerous plant developmental processes and is described to be of critical importance for pollen wall development. In the present study, a PG gene, BoMF25, was isolated from Brassica oleracea. BoMF25 is the homologous gene of At4g35670, a PG gene in Arabidopsis thaliana with a high expression level at the tricellular pollen stage. Collinear analysis revealed that the orthologous gene of BoMF25 in Brassica campestris (syn. B. rapa) genome was probably lost because of genome deletion and reshuffling. Sequence analysis indicated that BoMF25 contained four classical conserved domains (I, II, III, and IV) of PG protein. Homology and phylogenetic analyses showed that BoMF25 was clustered in Clade F. The putative promoter sequence, containing classical cis-acting elements and pollen-specific motifs, could drive green fluorescence protein expression in onion epidermal cells. Quantitative RT-PCR analysis suggested that BoMF25 was mainly expressed in the anther at the late stage of pollen development. In situ hybridization analysis also indicated that the strong and specific expression signal of BoMF25 existed in pollen grains at the mature pollen stage. Subcellular localization showed that the fluorescence signal was observed in the cell wall of onion epidermal cells, which suggested that BoMF25 may be a secreted protein localized in the pollen wall.

  4. Down-regulation of POLYGALACTURONASE1 alters firmness, tensile strength and water loss in apple (Malus x domestica) fruit.

    Science.gov (United States)

    Atkinson, Ross G; Sutherland, Paul W; Johnston, Sarah L; Gunaseelan, Kularajathevan; Hallett, Ian C; Mitra, Deepali; Brummell, David A; Schröder, Roswitha; Johnston, Jason W; Schaffer, Robert J

    2012-08-02

    While there is now a significant body of research correlating apple (Malus x domestica) fruit softening with the cell wall hydrolase ENDO-POLYGALACTURONASE1 (PG1), there is currently little knowledge of its physiological effects in planta. This study examined the effect of down regulation of PG1 expression in 'Royal Gala' apples, a cultivar that typically has high levels of PG1, and softens during fruit ripening. PG1-suppressed 'Royal Gala' apples harvested from multiple seasons were firmer than controls after ripening, and intercellular adhesion was higher. Cell wall analyses indicated changes in yield and composition of pectin, and a higher molecular weight distribution of CDTA-soluble pectin. Structural analyses revealed more ruptured cells and free juice in pulled apart sections, suggesting improved integrity of intercellular connections and consequent cell rupture due to failure of the primary cell walls under stress. PG1-suppressed lines also had reduced expansion of cells in the hypodermis of ripe apples, resulting in more densely packed cells in this layer. This change in morphology appears to be linked with reduced transpirational water loss in the fruit. These findings confirm PG1's role in apple fruit softening and suggests that this is achieved in part by reducing cellular adhesion. This is consistent with previous studies carried out in strawberry but not with those performed in tomato. In apple PG1 also appears to influence other fruit texture characters such as juiciness and water loss.

  5. Isolation and characterization of a tomato non-specific lipid transfer protein involved in polygalacturonase-mediated pectin degradation.

    Science.gov (United States)

    Tomassen, Monic M M; Barrett, Diane M; van der Valk, Henry C P M; Woltering, Ernst J

    2007-01-01

    An important aspect of the ripening process of tomato fruit is softening. Softening is accompanied by hydrolysis of the pectin in the cell wall by pectinases, causing loss of cell adhesion in the middle lamella. One of the most significant pectin-degrading enzymes is polygalacturonase (PG). Previous reports have shown that PG in tomato may exist in different forms (PG1, PG2a, PG2b, and PGx) commonly referred to as PG isoenzymes. The gene product PG2 is differentially glycosylated and is thought to associate with other proteins to form PG1 and PGx. This association is thought to modulate its pectin-degrading activity in planta. An 8 kDa protein that is part of the tomato PG1 multiprotein complex has been isolated, purified, and functionally characterized. This protein, designated 'activator' (ACT), belongs to the class of non-specific lipid transfer proteins (nsLTPs). ACT is capable of 'converting' the gene product PG2 into a more active and heat-stable form, which increases PG-mediated pectin degradation in vitro and stimulates PG-mediated tissue breakdown in planta. This finding suggests a new, not previously identified, function for nsLTPs in the modification of hydrolytic enzyme activity. It is proposed that ACT plays a role in the modulation of PG activity during tomato fruit softening.

  6. Activity of β-Galactosidase and Polygalacturonase in Zucchini Squash (Cucurbita pepo L. Stored at Low Temperatures

    Directory of Open Access Journals (Sweden)

    René Renato Balandrán-Quintana

    2007-01-01

    Full Text Available When fruits are exposed to chilling temperatures, enzymatic systems are affected and normal cell metabolism is altered; cell wall enzymes are the least studied in this respect. Our objective is to determine the effect of storage temperature and/or kind of tissue on the activity of the enzymes polygalacturonase (PG and β-galactosidase (β-gal in zucchini squash (Cucurbita pepo L. subjected to 2.5 and/or 12 °C for 16 days. Exocarp and endocarp samples were analyzed every 4 days for PG and β-gal activities. The highest β-gal activity was found in the exocarp at 12 °C; in both tissues β-gal decreased with time at 2.5 °C, but increased at 12 °C. PG activity was higher in the endocarp (highest activity at 2.5 °C than in the exocarp (highest activity at 12 °C. It was concluded that PG activity in the exocarp constitutes an adequate system for studying the relationship between chilling injury and cell wall biological activity.

  7. A Novel Acid-Stable Endo-Polygalacturonase from Penicillium oxalicum CZ1028: Purification, Characterization, and Application in the Beverage Industry.

    Science.gov (United States)

    Cheng, Zhong; Chen, Dong; Lu, Bo; Wei, Yutuo; Xian, Liang; Li, Yi; Luo, Zhenzhen; Huang, Ribo

    2016-06-28

    Acidic endo-polygalacturonases are the major part of pectinase preparations and extensively applied in the clarification of fruits juice, vegetables extracts, and wines. However, most of the reported fungal endo-polygalacturonases are active and stable under narrow pH range and low temperatures. In this study, an acidic endo-polygalacturonase (EPG4) was purified and characterized from a mutant strain of Penicillium oxalicum. The N-terminal amino acid sequence of EPG4 (ATTCTFSGSNGAASASKSQT) was different from those of reported endopolygalacturonases. EPG4 displayed optimal pH and temperature at 5.0 and 60-70°C towards polygalacturonic acid (PGA), respectively, and was notably stable at pH 2.2-7.0. When tested against pectins, EPG4 showed enzyme activity over a broad acidic pH range (>15.0% activity at pH 2.2-6.0 towards citrus pectin; and >26.6% activity at pH 2.2-7.0 towards apple pectin). The Km and Vmax values were determined as 1.27 mg/ml and 5,504.6 U/mg, respectively. The enzyme hydrolyzed PGA in endo-manner, releasing oligo-galacturonates from PGA, as determined by TLC. Addition of EPG4 (3.6 U/ml) significantly reduced the viscosity (by 42.4%) and increased the light transmittance (by 29.5%) of the papaya pulp, and increased the recovery (by 24.4%) of the papaya extraction. All of these properties make the enzyme a potential application in the beverage industry.

  8. Down-regulation of POLYGALACTURONASE1 alters firmness, tensile strength and water loss in apple (Malus x domestica fruit

    Directory of Open Access Journals (Sweden)

    Atkinson Ross G

    2012-08-01

    Full Text Available Abstract Background While there is now a significant body of research correlating apple (Malus x domestica fruit softening with the cell wall hydrolase ENDO-POLYGALACTURONASE1 (PG1, there is currently little knowledge of its physiological effects in planta. This study examined the effect of down regulation of PG1 expression in ‘Royal Gala’ apples, a cultivar that typically has high levels of PG1, and softens during fruit ripening. Results PG1-suppressed ‘Royal Gala’ apples harvested from multiple seasons were firmer than controls after ripening, and intercellular adhesion was higher. Cell wall analyses indicated changes in yield and composition of pectin, and a higher molecular weight distribution of CDTA-soluble pectin. Structural analyses revealed more ruptured cells and free juice in pulled apart sections, suggesting improved integrity of intercellular connections and consequent cell rupture due to failure of the primary cell walls under stress. PG1-suppressed lines also had reduced expansion of cells in the hypodermis of ripe apples, resulting in more densely packed cells in this layer. This change in morphology appears to be linked with reduced transpirational water loss in the fruit. Conclusions These findings confirm PG1’s role in apple fruit softening and suggests that this is achieved in part by reducing cellular adhesion. This is consistent with previous studies carried out in strawberry but not with those performed in tomato. In apple PG1 also appears to influence other fruit texture characters such as juiciness and water loss.

  9. Optimization of the Production of Polygalacturonase from Aspergillus kawachii Cloned in Saccharomyces cerevisiae in Batch and Fed-Batch Cultures

    Directory of Open Access Journals (Sweden)

    Diego Jorge Baruque

    2011-01-01

    Full Text Available Polygalacturonases (PG; EC 3.2.1.15 catalyze the hydrolysis of pectin and/or pectic acid and are useful for industrial applications such as juice clarification and pectin extraction. Growth and heterologous expression of recombinant Saccharomyces cerevisiae which expresses an acidic PG from Aspergillus kawachii has been studied in batch and fed-batch cultures. Kinetics and stoichiometric parameters of the recombinant yeast were determined in batch cultures in a synthetic medium. In these cultures, the total biomass concentration, protein concentration, and enzyme activity achieved were 2.2 g/L, 10 mg/L, and 3 U/mL, respectively, to give a productivity of 0.06 U/(mL·h. In fed-batch cultures, various strategies for galactose feeding were used: (i after a glucose growth phase, the addition of a single pulse of galactose which gave a productivity of 0.19 U/(mL·h; (ii after a glucose growth phase, a double pulse of galactose at the same final concentration was added, resulting in a productivity of 0.21 U/(mL·h; (iii a simultaneous feeding of glucose and galactose, yielding a productivity of 1.32 U/(mL·h. Based on these results, the simultaneous feeding of glucose and galactose was by far the most suitable strategy for the production of this enzyme. Moreover, some biochemical characteristics of the recombinant enzyme such as a molecular mass of ~60 kDa, an isoelectric point of 3.7 and its ability to hydrolyze polygalacturonic acid at pH=2.5 were determined.

  10. Cloning, Expression and Characterization of a Novel Thermophilic Polygalacturonase from Caldicellulosiruptor bescii DSM 6725

    Directory of Open Access Journals (Sweden)

    Yanyan Chen

    2014-04-01

    Full Text Available We cloned the gene ACM61449 from anaerobic, thermophilic Caldicellulosiruptor bescii, and expressed it in Escherichia coli origami (DE3. After purification through thermal treatment and Ni-NTA agarose column extraction, we characterized the properties of the recombinant protein (CbPelA. The optimal temperature and pH of the protein were 72 °C and 5.2, respectively. CbPelA demonstrated high thermal-stability, with a half-life of 14 h at 70 °C. CbPelA also showed very high activity for polygalacturonic acid (PGA, and released monogalacturonic acid as its sole product. The Vmax and Km of CbPelA were 384.6 U·mg−1 and 0.31 mg·mL−1, respectively. CbPelA was also able to hydrolyze methylated pectin (48% and 10% relative activity on 20%–34% and 85% methylated pectin, respectively. The high thermo-activity and methylated pectin hydrolization activity of CbPelA suggest that it has potential applications in the food and textile industry.

  11. Claviceps purpurea expressing polygalacturonases escaping PGIP inhibition fully infects PvPGIP2 wheat transgenic plants but its infection is delayed in wheat transgenic plants with increased level of pectin methyl esterification.

    Science.gov (United States)

    Volpi, Chiara; Raiola, Alessandro; Janni, Michela; Gordon, Anna; O'Sullivan, Donal M; Favaron, Francesco; D'Ovidio, Renato

    2013-12-01

    Claviceps purpurea is a biotrophic fungal pathogen of grasses causing the ergot disease. The infection process of C. purpurea on rye flowers is accompanied by pectin degradation and polygalacturonase (PG) activity represents a pathogenicity factor. Wheat is also infected by C. purpurea and we tested whether the presence of polygalacturonase inhibiting protein (PGIP) can affect pathogen infection and ergot disease development. Wheat transgenic plants expressing the bean PvPGIP2 did not show a clear reduction of disease symptoms when infected with C. purpurea. To ascertain the possible cause underlying this lack of improved resistance of PvPGIP2 plants, we expressed both polygalacturonases present in the C. purpurea genome, cppg1 and cppg2 in Pichia pastoris. In vitro assays using the heterologous expressed PGs and PvPGIP2 showed that neither PG is inhibited by this inhibitor. To further investigate the role of PG in the C. purpurea/wheat system, we demonstrated that the activity of both PGs of C. purpurea is reduced on highly methyl esterified pectin. Finally, we showed that this reduction in PG activity is relevant in planta, by inoculating with C. purpurea transgenic wheat plants overexpressing a pectin methyl esterase inhibitor (PMEI) and showing a high degree of pectin methyl esterification. We observed reduced disease symptoms in the transgenic line compared with null controls. Together, these results highlight the importance of pectin degradation for ergot disease development in wheat and sustain the notion that inhibition of pectin degradation may represent a possible route to control of ergot in cereals. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  12. Cloning and characterisation of a putative pollen-specific polygalacturonase gene (CpPG1) differentially regulated during pollen development in zucchini (Cucurbita pepo L.).

    Science.gov (United States)

    Carvajal, F; Garrido, D; Jamilena, M; Rosales, R

    2014-03-01

    Studies in zucchini (Cucurbita pepo L. spp. pepo) pollen have been limited to the viability and morphology of the mature pollen grain. The enzyme polygalacturonase (PG) is involved in pollen development and pollination in many species. In this work, we study anther and pollen development of C. pepo and present the cloning and characterisation of a putative PG CpPG1 (Accession no. HQ232488) from pollen cDNA in C. pepo. The predicted protein for CpPG1 has 416 amino acids, with a high homology to other pollen PGs, such as P22 from Oenothera organensis (76%) and PGA3 from Arabidopsis thaliana (73%). CpPG1 belongs to clade C, which comprises PGs expressed in pollen, and presents a 34 amino acid signal peptide for secretion towards the cell wall. DNA-blot analysis revealed that there are at least another two genes that code for PGs in C. pepo. The spatial and temporal accumulation of CpPG1 was studied by semi-quantitative- and qRT-PCR. In addition, mRNA was detected only in anthers, pollen and the rudimentary anthers of bisexual flowers (only present in some zucchini cultivars under certain environmental conditions that trigger anther development in the third whorl of female flowers). However, no expression was detected in cotyledons, stem or fruit. Furthermore, CpPG1 mRNA was accumulated throughout anther development, with the highest expression found in mature pollen. Similarly, exo-PG activity increased from immature anther stages to mature anthers and mature pollen. Overall, these data support the pollen specificity of this gene and suggest an involvement of CpPG1 in pollen development in C. pepo. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  13. Co-expression of an Erwinia chrysanthemi pectate lyase-encoding gene (pelE) and an E. carotovora polygalacturonase-encoding gene (peh1) in Saccharomyces cerevisiae.

    Science.gov (United States)

    Laing, E; Pretorius, I S

    1993-05-01

    A pectate lyase (PL)-encoding gene (pelE) from Erwinia chrysanthemi and a polygalacturonase (PG)-encoding gene (peh1) from E. carotovora were each inserted between a novel yeast expression-secretion cassette and a yeast gene terminator, and cloned separately into a yeast-centromeric shuttle vector (YCp50), generating recombinant plasmids pAMS12 and pAMS13. Transcription initiation signals present in the expression-secretion cassette were derived from the yeast alcohol dehydrogenase gene promoter (ADC1P), whereas the transcription termination signals were derived from the yeast tryptophan synthase gene terminator (TRP5T). Secretion of PL and PG was directed by the signal sequence of the yeast mating pheromone alpha-factor (MF alpha 1s). A pectinase cassette comprising ADC1P-MF alpha 1s-pelE-TRP5T and ADC1P-MF alpha 1s-peh1-TRP5T was subcloned into YCp50, generating plasmid pAMS14. Subsequently, the dominant selectable Geneticin G418-resistance (GtR) marker, APH1, inserted between the yeast uridine diphosphoglucose 4-epimerase gene promoter (GAL10P) and yeast orotidine-5'-phosphate carboxylase gene terminator (URA3T), was cloned into pAMS14, resulting in plasmid pAMS15. Plasmids pAMS12, pAMS13 and pAMS14 were transformed into a laboratory strain of Saccharomyces cerevisiae, whereas pAMS15 was stably introduced into two commercial wine yeast strains. DNA-DNA and DNA-RNA hybridization analyses revealed the presence of these plasmids, and the pelE and peh1 transcripts in the yeast transformants, respectively. A polypectate agarose assay indicated the extracellular production of biologically active PL and PG by the S. cerevisiae transformants and confirmed that co-expression of the pelE and peh1 genes synergistically enhanced pectate degradation.

  14. Biochemical Characterization, Thermal Stability, and Partial Sequence of a Novel Exo-Polygalacturonase from the Thermophilic Fungus Rhizomucor pusillus A13.36 Obtained by Submerged Cultivation

    Directory of Open Access Journals (Sweden)

    Lucas Vinícius Trindade

    2016-01-01

    Full Text Available This work reports the production of an exo-polygalacturonase (exo-PG by Rhizomucor pusillus A13.36 in submerged cultivation (SmC in a shaker at 45°C for 96 h. A single pectinase was found and purified in order to analyze its thermal stability, by salt precipitation and hydrophobic interaction chromatography. The pectinase has an estimated Mw of approximately 43.5–47 kDa and optimum pH of 4.0 but is stable in pH ranging from 3.5 to 9.5 and has an optimum temperature of 61°C. It presents thermal stability between 30 and 60°C, has 70% activation in the presence of Ca2+, and was tested using citrus pectin with a degree of methyl esterification (DE of 26%. Ea(d for irreversible denaturation was 125.5 kJ/mol with positive variations of entropy and enthalpy for that and ΔG(d values were around 50 kJ/mol. The hydrolysis of polygalacturonate was analyzed by capillary electrophoresis which displayed a pattern of sequential hydrolysis (exo. The partial identification of the primary sequence was done by MS MALDI-TOF and a comparison with data banks showed the highest identity of the sequenced fragments of exo-PG from R. pusillus with an exo-pectinase from Aspergillus fumigatus. Pectin hydrolysis showed a sigmoidal curve for the Michaelis-Menten plot.

  15. Effect of temperature and pH on polygalacturonase production by pectinolytic bacteria Bacillus licheniformis strain GD2a in submerged medium from Raja Nangka (Musa paradisiaca var. formatypica) banana peel waste

    Science.gov (United States)

    Widowati, E.; Utami, R.; Mahadjoeno, E.; Saputro, G. P.

    2017-04-01

    The aim of this research were to determine the effect of temperature (45°C, 55°C, 65°C) and pH (5.0; 6.0; 7.0) on the increase of total cell count and polygalacturonase enzyme activity produced from raja nangka banana (Musa paradisiaca var. formatypica) peel waste by pectinolytic bacterial Bacillus licheniformis strain GD2a. This research applied two sample repetition and one analysis repetition. The result showed temperature and pH affect total cell count. The total cell count on 45°C and pH 7 recorded the highest number at 9.469 log cell/ml. Temperature and pH also affected pectin concentration at the end of fermentation. The lowest pectin concentration recorded at 45°C and pH 7 was 0.425 %. The highest enzyme activity recorded at 65°C and pH 7 was 0.204 U/ml. The highest enzyme protein concentration was recorded at 65°C and resulted as 0.310 mg/ml on pH 6. The highest specific activity was 19.527 U/mg at 65°C and pH 7. By this result, could be concluded that optimum condition process on polygalacturonase production was at 65°C and pH 7 because it gave highest enzyme activity result (0,204 U/ml).

  16. Influence of carbon source, pH, and temperature on the polygalacturonase activity of Kluyveromyces marxianus CCMB 322 Influência da fonte de carbono, pH e temperatura na atividade da enzima poligalacturonase de Kluyveromyces marxianus CCMB 322

    Directory of Open Access Journals (Sweden)

    Rodrigo de Queiroz Oliveira

    2012-09-01

    Full Text Available Microbial pectinolytic enzymes are known to play a commercially important role in a number of industrial processes. Two kinds of yeast can be discerned regarding the production of enzymes. One group includes those which can produce enzymes in the absence of an inducer, and the other group comprises the yeasts that produce enzymes in the presence of an inducer. The objective of this study was to investigate the influence of pectic substances, glucose, pH, and temperature on the polygalacturonase activity by Kluyveromyces marxianus CCMB 322. The yeast was grown in a fermentation broth containing different concentrations of glucose and pectic substances. The polygalacturonase activity was determined by the DNS method, and the pH and temperature were optimized using a central composite experimental design. The polygalacturonase secreted by K. marxianus CCMB 322 was partially constitutive showing optimum pH and temperature of 7.36 and 70 °C, respectively, and maintained approximately 93% of its original activity for 50 minutes at 50 °C. Thermal stability of the polygalacturonase enzyme was studied at different temperatures (50, 60, 70, and 80 °C and different incubation times (0, 10, 20, 30, 40, and 50 minutes. This study showed that glucose can influence the regulation of the synthesis of polygalacturonase.Enzimas pectinolíticas de origem microbiana são conhecidas por desempenhar um papel importante comercialmente em uma série de processos industriais. Dois tipos de levedura podem ser distinguidos para a produção dessas enzimas. Um grupo inclui aqueles que têm capacidade de produzi-las na ausência de um indutor e outro grupo compreende as leveduras que as produzem na presença de um indutor. O objetivo deste estudo foi investigar a influência de substâncias pécticas, de glicose, do pH e da temperatura na atividade da poligalacturonase de Kluyveromyces marxianus CCMB 322. O cultivo foi em caldo de fermentação contendo diferentes

  17. Ripening-induced changes in microbial groups of artisanal Sicilian goats’ milk cheese

    Directory of Open Access Journals (Sweden)

    Vincenzo Di Marco

    2010-01-01

    Full Text Available Changes in the microbial flora of “Caprino dei Nebrodi”, a raw goat’s milk cheese produced in Sicily, were studied during ripening. From 2 batches of cheese, 4 samples were taken at day 0, 2, 15, and 30 of ripening. Also, samples of curd and milk used in the manufacturing process were analyzed. By the end of the ripening process (day 30, high log10 cfu/g were found for Lactobacilli (7.20, Lattococci (7.10, and Enterococci (7.00, whereas counts of Enterobacteriaceae (3.91, Escherichia coli (3.30, and Staphylococcus (3.89 were found to be lower. The study provides useful information on the microbiological properties of “Caprino dei Nebrodi” cheese, and the results obtained suggest that in order to increase the quality of this artisanal product, it is necessary to improve the sanitary conditions of milking and cheese-making. The study was intended as a preliminary step towards the isolation and identification of bacterial species found in this type of goat’s cheese.

  18. Relativity

    CERN Document Server

    Einstein, Albert

    2013-01-01

    Time magazine's ""Man of the Century"", Albert Einstein is the founder of modern physics and his theory of relativity is the most important scientific idea of the modern era. In this short book, Einstein explains, using the minimum of mathematical terms, the basic ideas and principles of the theory that has shaped the world we live in today. Unsurpassed by any subsequent books on relativity, this remains the most popular and useful exposition of Einstein's immense contribution to human knowledge.With a new foreword by Derek Raine.

  19. Pectinase and polygalacturonase production by a thermophilic Aspergillus fumigatus isolated from decomposting orange peels Produção de pectinases e poligalacturonase por Aspergillus fumigatus termofílico isolado de cascas de laranja em decomposição

    Directory of Open Access Journals (Sweden)

    Urmila Phutela

    2005-03-01

    Full Text Available A thermophilic fungal strain producing both pectinase and polygalacturonase was isolated after primary screening of 120 different isolates. The fungus was identified as Aspergillus fumigatus Fres. MTCC 4163. Using solid-state cultivation, the optimum levels of variables for pectinase and polygalacturonase (PG production were determined. Maximal levels of enzyme activities were achieved upon growing the culture in a medium containing wheat bran, sucrose, yeast extract and (NH42SO4 after 2-3 days of incubation at a temperature of 50ºC. Highest enzyme activities of 1116 Ug-1 for pectinase and 1270 Ug-1 for polygalacturonase were obtained at pH 4.0 and 5.0, respectively.Através da tiragem de 120 cepas de fungos, isolou-se uma cepa capaz de produzir tanto pectinase quanto poligalacturonase. A cepa foi identificada como Aspergillus fumigatus Fres. MTCC 4163. Empregando cultivo em estado sólido, determinou-se os níveis ótimos das variáveis para a produção de pectinase e de poligalacturonase. Os níveis máximos de atividade enzimática foram obtidos quando a cultura era realizada em meio contendo farelo de trigo, sacarose, extrato de levedura e (NH42SO4 por 2-3 dias a uma temperatura de 50ºC. A atividade máxima de pectinase (1116 Ug-1 e de poligalacturonase (1270 Ug-1 foi obtida em pH 4,0 e 5,0, respectivamente.

  20. Partial purification and characterization of polygalacturonase ...

    African Journals Online (AJOL)

    Yomi

    2012-04-03

    Apr 3, 2012 ... Protein separation of the two peaks by gel electrophoresis .... wise increase in the salt gradient (100, 200, 300, 400, 500 and. 1000 mM NaCl) in the ..... retained some residual inhibitory activity even at 90°C. (Shivshanker et al.

  1. Determination of extra and intracellular content from some lytic enzymes related with carnation (Dianthus caryophyllus L. root cell wall

    Directory of Open Access Journals (Sweden)

    Sixta Tulia Martínez Peralta

    2016-11-01

    Full Text Available The presence of some enzymes related to cell wall (polygalacturonase, the pectate lyase, protease and xylanase in carnation (Dianthus caryophyllus L. roots as well as the activity levels were determined. These levels were analyzed in different cellular places: the intercellular fluid that is part of apoplast, the symplast, and the total level (apoplast and symplast in carnation roots. Two methods were tested to extract the intercellular fluid. To obtain the intracellular content (symplast and total extract (apoplast+symplast, three methods were tested, using as extracting solution  i phosphate buffer, ii phosphate buffer + PVPP,  iii before the extraction with phosphate buffer, the carnation roots were washed with acetone.  The results showed the effect of different extracting solutions in the enzymatic activities and in the protein content. A new only one step method is proposed to extract the four enzymes and make the comparative analysis of enzymatic activity.

  2. Unraveling the enzymatic basis of wine flavorome: a phylo-functional study of wine related yeast species

    Directory of Open Access Journals (Sweden)

    Ignacio eBelda

    2016-01-01

    Full Text Available Non-Saccharomyces yeasts are a heterogeneous microbial group involved in the early stages of wine fermentation. The high enzymatic potential of these yeasts makes them a useful tool for increasing the final organoleptic characteristics of wines in spite of their low fermentative power. Their physiology and contribution to wine quality are still poorly understood, with most current knowledge being acquired empirically and in most cases based in single species and strains. This work analyzed the metabolic potential of 770 yeast isolates from different enological origins and representing 15 different species, by studying their production of enzymes of enological interest and linking phylogenetic and enzymatic data. The isolates were screened for glycosidase enzymes related to terpene aroma release, the β-lyase activity responsible for the release of volatile thiols, and sulfite reductase. Apart from these aroma-related activities, protease, polygalacturonase and cellulase activities were also studied in the entire yeast collection, being related to the improvement of different technological and sensorial features of wines. In this context, and in terms of abundance, two different groups were established, with α-L-arabinofuranosidase, polygalacturonase and cellulase being the less abundant activities. By contrast, β-glucosidase and protease activities were widespread in the yeast collection studied.A classical phylogenetic study involving the partial sequencing of 26S rDNA was conducted in conjunction with the enzymatic profiles of the 770 yeast isolates for further typing, complementing the phylogenetic relationships established by using 26S rDNA. This has rendered it possible to foresee the contribution different yeast species make to wine quality and their potential applicability as pure inocula, establishing species-specific behavior. These consistent results allowed us to design future targeted studies on the impact different non

  3. Influence of metal ions on pellet morphology and polygalacturonase synthesis by Aspergillus niger 3T5B8 Influência dos íons metálicos na morfologia do agregado e na síntese de poligalacturonase por Aspergillus niger 3T5B8

    Directory of Open Access Journals (Sweden)

    Sônia Couri

    2003-04-01

    Full Text Available The effects of cations addition on pellet morphology and polygalacturonase (PG synthesis by Aspergillus niger 3T5B8 were studied and compared with a control system. Fe(II, Cu(II, Zn(II and Mn(II were added to the fermentation medium separately, and also as combined groups of cations. The addition of Fe2+ and/or Zn2+ ions was significantly positive to the enzyme production. A positive effect in the biomass content, however, was only obtained when the same metal ions were added separately. On the other hand, Cu2+ and Mn2+ ions had almost no effect on these parameters. The morphology of the pellets was studied by image processing techniques. Small pellets with small cores were usually obtained when Fe2+ and Zn2+ ions were individually or collectively added to the medium. The pellets produced in media containing Fe2+ or Zn2+ ions were compact, while the ones produced in a medium containing both cations were considered diffuse. Autolysis of the core was observed for large control pellets, due to the deficient nutrient transfer to the interior of the pellet. The pellets obtained in a medium containing both Fe2+ and Zn2+ ions were high enzyme producers, probably due to a loose morphology, induced by the presence of combined groups of metal ions in the medium, favoring the nutrient transfer.O efeito da adição de cátions na morfologia do agregado e na síntese de poligalacturonase (PG por Aspergillus niger 3T5B8 foi estudado e comparado com um sistema controle. Fe(II, Cu(II, Zn(II and Mn(II foram adicionados ao meio de fermentação, tanto separadamente, como em grupos de cátions. A adição dos íons Fe2+ e/ou Zn2+ foi positivamente significante para a produção da enzima. Um efeito similar no teor de biomassa, contudo, só pode ser observado quando os mesmos íons foram adicionados isoladamente. Por outro lado, os íons Cu2+ e Mn2+ não afetaram significativamente estes parâmetros. Utilizando-se técnicas de processamento de imagens para o estudo

  4. [Induction of polygalacturonases important in pathogenicity of Pseudomonas solanacearum

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    Recent studies on the importance of hydroxyproline-rich glycoproteins (HPRG`s) in the nature and function of plant cell walls have led to the question as to whether proteolytic enzymes are also involved in tissue maceration and act in concert with other cell wall degrading enzymes in the process. The primary objective of this research was to determine whether proteolytic enzymes, in combination with other enzymes, are involved in the degradation of plant cell walls and thus may be essential for pathogenesis by certain soft rot bacteria. The proteolytic enzymes of Erwinia carotovora subsp.carotovora (Ecc) grown on various media were examined by isoelectrofocusing in polyacrylamide gels over a pH range of 3-10. In addition to the main protease present in culture filtrates, low concentrations of several other proteases were present in extracts from potato tubers infected by Ecc. These enzymes degraded gelatin, soluble collagen, and Hide Powder Azure, and showed weak activity on casein, but did not degrade insoluble collagen or elastin. Ecc proteases appear capable of degrading at least one type of cell wall protein in vitro, but we were unable to obtain evidence that these proteases can attack cell wall proteins in muro. The results indicate that some glycosidic alkali- labile bonds have to be broken befor Ecc proteases can degrade cell wall proteins. Thus, these proteases may play a role in cell wall degradation only when acting in concert with other enzymes that split glycosidic bonds.

  5. [Induction of polygalacturonases important in pathogenicity of Pseudomonas solanacearum

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Recent studies on the importance of hydroxyproline-rich glycoproteins (HPRG's) in the nature and function of plant cell walls have led to the question as to whether proteolytic enzymes are also involved in tissue maceration and act in concert with other cell wall degrading enzymes in the process. The primary objective of this research was to determine whether proteolytic enzymes, in combination with other enzymes, are involved in the degradation of plant cell walls and thus may be essential for pathogenesis by certain soft rot bacteria. The proteolytic enzymes of Erwinia carotovora subsp.carotovora (Ecc) grown on various media were examined by isoelectrofocusing in polyacrylamide gels over a pH range of 3-10. In addition to the main protease present in culture filtrates, low concentrations of several other proteases were present in extracts from potato tubers infected by Ecc. These enzymes degraded gelatin, soluble collagen, and Hide Powder Azure, and showed weak activity on casein, but did not degrade insoluble collagen or elastin. Ecc proteases appear capable of degrading at least one type of cell wall protein in vitro, but we were unable to obtain evidence that these proteases can attack cell wall proteins in muro. The results indicate that some glycosidic alkali- labile bonds have to be broken befor Ecc proteases can degrade cell wall proteins. Thus, these proteases may play a role in cell wall degradation only when acting in concert with other enzymes that split glycosidic bonds.

  6. Identification of a partial oil palm polygalacturonase-inhibiting ...

    African Journals Online (AJOL)

    Basal stem rot disease (BSR) is a common and serious fungal disease of the oil palm caused by Ganoderma boninense. This fungal disease infects thousands of hectares of plantings in Southeast Asia every year causing not only yield but also tree losses. A natural plant self defence mechanism against fungal infection is ...

  7. Production and partial characterization of polygalacturonases produced by thermophilic Monascus sp N8 and by thermotolerant Aspergillus sp N12 on solid-state fermentation Produção e caracterização parcial de poligalacturonases produzidas pelo fungo termofílico Monascus sp N8 e pelo termotolerante Aspergillus sp N12 em fermentação em estado sólido

    Directory of Open Access Journals (Sweden)

    Paula Mendes de Freitas

    2006-09-01

    Full Text Available Polygalacturonases production by newly isolated Monascus sp N8 and Aspergillus sp N12 strains was carried out in solid-state fermentation using mixtures of wheat bran, sugar cane bagasse and orange bagasse as carbon sources. The maximal activity values of exo-polygalacturonases (exo-Pg from Monascus sp and Aspergillus sp were obtained using wheat bran/sugar cane bagasse/orange bagasse mixture (6.6 U/mL and wheat bran/orange bagasse mixture (10 U/mL, respectively. Enzyme production by both strains was higher at 45ºC after 72 h and 1.6 U/mL at 50ºC after 120 h. Endo-polygalacturonase (endo-Pg production was higher in wheat bran/orange bagasse mixture and was not affected by temperature of incubation for both fungi. Endo-Pg production by Monascus was 1.8 U/mL at 45ºC and 50ºC, after 72. Similar values were obtained in Aspergillus sp culture, 1.9 U/mL at 45ºC and 1.8 U/mL at 50ºC. Exo-Pg from both strains showed optimum activity at pH 5.5. Maximal activity was determined at 60ºC for enzyme from Monascus sp and 50ºC for that produced by Aspergillus sp. Exo-Pg from Monascus sp was stable at pH range 4.5-6.0 whereas that from Aspergillus sp enzyme was stable at pH 4.0. Both enzymes showed stability when incubated at 50ºC for 1 h, in absence of substrate.A produção de poligalacturonases pelas linhagens fúngicas recentemente isoladas, Monascus sp N8 e Aspergillus sp N12, foi estudada através de fermentação em estado sólido usando como substratos misturas de farelo de trigo, bagaço da cana-de-açúcar e bagaço de laranja. A atividade máxima de exo-Pg produzida por Monascus sp (6,6 U/mL foi obtida quando o meio de cultivo utilizado continha mistura de farelo de trigo, bagaço da cana-de-açúcar e bagaço de laranja (1:1:1, enquanto que Aspergillus sp produziu maior quantidade da enzima (10 U/mL em meio de farelo de trigo e bagaço de laranja. A maior produção de exo-Pg foi obtida através de incubação das culturas a 45ºC quando

  8. Mudanças relacionadas ao amaciamento da graviola durante a maturação pós-colheita Changes related to softening of soursop during postharvest maturation

    Directory of Open Access Journals (Sweden)

    Maria Auxiliadora Coêlho de Lima

    2006-12-01

    Full Text Available Este trabalho teve por objetivo avaliar mudanças físicas, químicas e bioquímicas relacionadas ao amaciamento de graviola (Annona muricata L. Crioula durante a maturação. Os frutos foram colhidos no estádio de maturidade fisiológica, em plantas cultivadas na Estação Experimental da Embrapa Agroindústria Tropical, em Pacajus, Ceará, armazenados a 26,3±0,6 ºC e 88±12% de umidade relativa, durante 1, 2, 3, 4 e 5 dias. Utilizou-se o delineamento experimental inteiramente casualizado, com quatro repetições. As variáveis analisadas foram: perda de massa, amido, pectina total e solúvel, e atividades das enzimas amilase, pectinametilesterase, poligalacturonase, alfa-galactosidases e beta-galactosidases. Não houve variação significativa no conteúdo de pectina solúvel. Após cinco dias, a perda de massa atingiu 5%, mas não promoveu murcha dos frutos. As reduções nos conteúdos de amido e de pectina total coincidiram com período de expressiva atividade, respectivamente, das enzimas amilase e da poligalacturonase e beta-galactosidase de parede celular. As modificações mais acentuadas no conteúdo de amido, de pectina total, na solubilização de pectinas e na atividade das enzimas amilase, pectinametilesterase, poligalacturonase e beta-galactosidase de parede celular ocorreram no período do segundo ao quarto dia após a colheita.This work aimed to evaluate the physical, chemical and biochemical changes related to softening during maturation of Crioula soursop fruit (Annona muricata L.. Fruits were harvested at the physiological maturity stage from plants grown at Embrapa Agroindústria Tropical Experimental Station, in Pacajus, CE, Brazil, and were stored at 26.3±0.6 ºC and 88±12% relative humidity, during 1, 2, 3, 4 and 5 days. A completely randomized design was used with four replicates. The following variables were evaluated: weight loss; starch content; total and soluble pectin content and enzymatic activity of amylase

  9. Relativity made relatively easy

    CERN Document Server

    Steane, Andrew M

    2012-01-01

    Relativity Made Relatively Easy presents an extensive study of Special Relativity and a gentle (but exact) introduction to General Relativity for undergraduate students of physics. Assuming almost no prior knowledge, it allows the student to handle all the Relativity needed for a university course, with explanations as simple, thorough, and engaging as possible.The aim is to make manageable what would otherwise be regarded as hard; to make derivations as simple as possible and physical ideas as transparent as possible. Lorentz invariants and four-vectors are introduced early on, but tensor not

  10. Relativity without relativity

    International Nuclear Information System (INIS)

    Barbour, Julian; Foster, Brendan Z; Murchadha, Niall O

    2002-01-01

    We give a derivation of general relativity (GR) and the gauge principle that is novel in presupposing neither spacetime nor the relativity principle. We consider a class of actions defined on superspace (the space of Riemannian 3-geometries on a given bare manifold). It has two key properties. The first is symmetry under 3-diffeomorphisms. This is the only postulated symmetry, and it leads to a constraint linear in the canonical momenta. The second property is that the Lagrangian is constructed from a 'local' square root of an expression quadratic in the velocities. The square root is 'local' because it is taken before integration over 3-space. It gives rise to quadratic constraints that do not correspond to any symmetry and are not, in general, propagated by the Euler-Lagrange equations. Therefore these actions are internally inconsistent. However, one action of this form is well behaved: the Baierlein-Sharp-Wheeler (Baierlein R F, Sharp D and Wheeler J A 1962 Phys. Rev. 126 1864) reparametrization-invariant action for GR. From this viewpoint, spacetime symmetry is emergent. It appears as a 'hidden' symmetry in the (underdetermined) solutions of the Euler-Lagrange equations, without being manifestly coded into the action itself. In addition, propagation of the linear diffeomorphism constraint together with the quadratic square-root constraint acts as a striking selection mechanism beyond pure gravity. If a scalar field is included in the configuration space, it must have the same characteristic speed as gravity. Thus Einstein causality emerges. Finally, self-consistency requires that any 3-vector field must satisfy Einstein causality, the equivalence principle and, in addition, the Gauss constraint. Therefore we recover the standard (massless) Maxwell equations

  11. Relational databases

    CERN Document Server

    Bell, D A

    1986-01-01

    Relational Databases explores the major advances in relational databases and provides a balanced analysis of the state of the art in relational databases. Topics covered include capture and analysis of data placement requirements; distributed relational database systems; data dependency manipulation in database schemata; and relational database support for computer graphics and computer aided design. This book is divided into three sections and begins with an overview of the theory and practice of distributed systems, using the example of INGRES from Relational Technology as illustration. The

  12. Social relations

    DEFF Research Database (Denmark)

    Due, P; Holstein, B; Lund, R

    1999-01-01

    We introduce a conceptual framework with social relations as the main concept and the structure and the function of social relations as subconcepts. The structure of social relations covers aspects of formal relations and social network. The function of social relations covers social support......, social anchorage and relational strain. We use this conceptual framework to describe social relations in the Danish population, with questionnaire data from the Danish Longitudinal Health Behaviour Study including a random sample of each of the age groups 25-, 50-, 60-and 70-year olds, N = 2......,011. The postal questionnaires were answered by a random sample in each of the age groups. The results show marked age and gender differences in both the structure and the function of social relations. The social network, measured as weekly contacts, weakens with age and so does instrumental support. Emotional...

  13. Relational Leadership

    DEFF Research Database (Denmark)

    Madsen, Charlotte Øland; Rasmussen, Jørgen Gulddahl

    2015-01-01

    In this chapter, we emphasise what we have outlined as interesting areas of relational leadership and present some ideas on how to facilitate a broader understanding of relational leadership practice. This involves the interpretations that create connections between practice and ontology. We...... elaborate on how leadership in everyday situations can be understood from a relational perspective. The chapter will focus on outlining and inspiring the reader to co-operate with other people to develop further relational understandings of leading....

  14. Special relativity

    International Nuclear Information System (INIS)

    Taylor, J.G.

    1975-01-01

    It is stated that the early chapters review special relativity from an elementary mathematical viewpoint, and include discussion of recent experiments which set out to test Einstein's predictions. The theory of relativity is then reformulated in more sophisticated mathematical language to show its relation to electro-magnetism, and to lay the foundation for more general viewpoints. The final chapter discusses in simple terms where activity in the field is currently centred, and where future interest lies. Chapter headings include: the constant speed of light; measuring time and distance; the Lorentz transformation (relativity of simultaneity, space-time and causality); relativistic kinematics (including - the Dopper effect); relativistic dynamics (including - nuclear binding energy, particle creation, electrodynamics); the structure of special relativity (including - the Lorentz group, the rotation group, elementary particle scattering); extensions of special relativity. (U.K.)

  15. International Relations

    OpenAIRE

    McGlinchey, S.

    2017-01-01

    A ‘Day 0’ introduction to International Relations for beginners. Written by a range of emerging and established experts, the chapters offer a broad sweep of the basic components of International Relations and the key contemporary issues that concern the discipline. The narrative arc forms a complete circle, taking readers from no knowledge to competency. The journey starts by examining how the international system was formed and ends by reflecting that International Relations is always adapti...

  16. Numerical relativity

    CERN Document Server

    Shibata, Masaru

    2016-01-01

    This book is composed of two parts: First part describes basics in numerical relativity, that is, the formulations and methods for a solution of Einstein's equation and general relativistic matter field equations. This part will be helpful for beginners of numerical relativity who would like to understand the content of numerical relativity and its background. The second part focuses on the application of numerical relativity. A wide variety of scientific numerical results are introduced focusing in particular on the merger of binary neutron stars and black holes.

  17. Public relations

    International Nuclear Information System (INIS)

    1998-01-01

    Public relations activities continued in a well-proved form of organizing plant visits and Information Centre off - site activities. Bohunice NPPs were visited by the number of 7294 visitors in 1997. A brief account of activities in public relations carried out by the Nuclear power plants Jaslovske Bohunice in 1997 is presented

  18. Numerical Relativity

    Science.gov (United States)

    Baker, John G.

    2009-01-01

    Recent advances in numerical relativity have fueled an explosion of progress in understanding the predictions of Einstein's theory of gravity, General Relativity, for the strong field dynamics, the gravitational radiation wave forms, and consequently the state of the remnant produced from the merger of compact binary objects. I will review recent results from the field, focusing on mergers of two black holes.

  19. General relativity

    International Nuclear Information System (INIS)

    Kenyon, I.R.

    1990-01-01

    General relativity is discussed in this book at a level appropriate to undergraduate students of physics and astronomy. It describes concepts and experimental results, and provides a succinct account of the formalism. A brief review of special relativity is followed by a discussion of the equivalence principle and its implications. Other topics covered include the concepts of curvature and the Schwarzschild metric, test of the general theory, black holes and their properties, gravitational radiation and methods for its detection, the impact of general relativity on cosmology, and the continuing search for a quantum theory of gravity. (author)

  20. Special relativity

    International Nuclear Information System (INIS)

    French, A.P.

    1982-01-01

    This book is an introduction to special relativity theory. After a discussion of the limits of Newton's mechanics and the pecularities in the propagation of light the Lorentz transformation is introduced. Then the measurement of space and time intervals in the framework of relativity theory is considered. Thereafter the addition of velocities and acceleration are considered in this framework. Then relativistic kinematics of particle interactions are described. Then the four-dimensional calculus in space-time coordinates is introduced. Finally an introduction is given to the treatment of the electromagnetic field in the framework of relativity theory. Every chapter contains exercise problems with solutions. This book is suited for all students who want to get some fundamental knowledge about relativity theory. (HSI) [de

  1. Relational Leading

    DEFF Research Database (Denmark)

    Larsen, Mette Vinther; Rasmussen, Jørgen Gulddahl

    2015-01-01

    This first chapter presents the exploratory and curious approach to leading as relational processes – an approach that pervades the entire book. We explore leading from a perspective that emphasises the unpredictable challenges and triviality of everyday life, which we consider an interesting......, relevant and realistic way to examine leading. The chapter brings up a number of concepts and contexts as formulated by researchers within the field, and in this way seeks to construct a first understanding of relational leading....

  2. Linguistic relativity.

    Science.gov (United States)

    Wolff, Phillip; Holmes, Kevin J

    2011-05-01

    The central question in research on linguistic relativity, or the Whorfian hypothesis, is whether people who speak different languages think differently. The recent resurgence of research on this question can be attributed, in part, to new insights about the ways in which language might impact thought. We identify seven categories of hypotheses about the possible effects of language on thought across a wide range of domains, including motion, color, spatial relations, number, and false belief understanding. While we do not find support for the idea that language determines the basic categories of thought or that it overwrites preexisting conceptual distinctions, we do find support for the proposal that language can make some distinctions difficult to avoid, as well as for the proposal that language can augment certain types of thinking. Further, we highlight recent evidence suggesting that language may induce a relatively schematic mode of thinking. Although the literature on linguistic relativity remains contentious, there is growing support for the view that language has a profound effect on thought. WIREs Cogni Sci 2011 2 253-265 DOI: 10.1002/wcs.104 For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

  3. General relativity

    International Nuclear Information System (INIS)

    Gourgoulhon, Eric

    2013-01-01

    The author proposes a course on general relativity. He first presents a geometrical framework by addressing, presenting and discussion the following notions: the relativistic space-time, the metric tensor, Universe lines, observers, principle of equivalence and geodesics. In the next part, he addresses gravitational fields with spherical symmetry: presentation of the Schwarzschild metrics, radial light geodesics, gravitational spectral shift (Einstein effect), orbitals of material objects, photon trajectories. The next parts address the Einstein equation, black holes, gravitational waves, and cosmological solutions. Appendices propose a discussion of the relationship between relativity and GPS, some problems and their solutions, and Sage codes

  4. Weak relativity

    CERN Document Server

    Selleri, Franco

    2015-01-01

    Weak Relativity is an equivalent theory to Special Relativity according to Reichenbach’s definition, where the parameter epsilon equals to 0. It formulates a Neo-Lorentzian approach by replacing the Lorentz transformations with a new set named “Inertial Transformations”, thus explaining the Sagnac effect, the twin paradox and the trip from the future to the past in an easy and elegant way. The cosmic microwave background is suggested as a possible privileged reference system. Most importantly, being a theory based on experimental proofs, rather than mutual consensus, it offers a physical description of reality independent of the human observation.

  5. Readable relativity

    CERN Document Server

    Durell, Clement V

    1962-01-01

    Concise and practical, this text by a renowned teacher sketches the mathematical background essential to understanding the fundamentals of relativity theory. Subjects include the velocity of light, measurement of time and distance, and properties of mass and momentum, with numerous diagrams, formulas, and examples, plus exercises and solutions. 1960 edition.

  6. Relative Utilitarianism

    OpenAIRE

    DHILLON, Amrita; MERTENS, Jean-François

    1993-01-01

    In a framework of preferences over lotteries, we show that an axiom system consisting of weakned versions of Arrow’s axioms has a unique solution. “Relative Utilitarianism” consists of first normalizing individual von Neumann-Morgenstern utilities between 0 and 1 and then summing them.

  7. Relative Hypovolaemia

    African Journals Online (AJOL)

    Adele

    the vascular space and the remainder of the extracellular fluid. (ECF) and intracellular ... diuretic therapy are likely to have a relative volume deficiency. Normovolaemia and .... and it is likely that alternative forms of assessment of this crucial measure will be ... necrosis factor and Interleukins1–6, histamine and serotonin.

  8. General Relativity

    CERN Document Server

    Straumann, Norbert

    2013-01-01

    This book provides a completely revised and expanded version of the previous classic edition ‘General Relativity and Relativistic Astrophysics’. In Part I the foundations of general relativity are thoroughly developed, while Part II is devoted to tests of general relativity and many of its applications. Binary pulsars – our best laboratories for general relativity – are studied in considerable detail. An introduction to gravitational lensing theory is included as well, so as to make the current literature on the subject accessible to readers. Considerable attention is devoted to the study of compact objects, especially to black holes. This includes a detailed derivation of the Kerr solution, Israel’s proof of his uniqueness theorem, and a derivation of the basic laws of black hole physics. Part II ends with Witten’s proof of the positive energy theorem, which is presented in detail, together with the required tools on spin structures and spinor analysis. In Part III, all of the differential geomet...

  9. International relations

    International Nuclear Information System (INIS)

    Anon.

    2008-01-01

    Concerning international relations, the different meetings in the field of nuclear safety are reported (Western european nuclear regulator association or Wenra, Nea, IAEA, northern dimension environmental partnership or N.D.E.P., nuclear safety and security group or N.S.S.G., international nuclear regulators association or I.N.R.A.). (N.C.)

  10. Relational Architecture

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2018-01-01

    in a scholarly institution (element #3), as well as the certified PhD scholar (element #4) and the architectural profession, notably its labour market (element #5). This first layer outlines the contemporary context which allows architectural research to take place in a dynamic relationship to doctoral education...... a human and institutional development going on since around 1990 when the present PhD institution was first implemented in Denmark. To be sure, the model is centred around the PhD dissertation (element #1). But it involves four more components: the PhD candidate (element #2), his or her supervisor...... and interrelated fields in which history, place, and sound come to emphasize architecture’s relational qualities rather than the apparent three-dimensional solidity of constructed space. A third layer of relational architecture is at stake in the professional experiences after the defence of the authors...

  11. International Relations:

    DEFF Research Database (Denmark)

    This is the textbook for the Open University module International Relations: Continuity and Change in Global Politics. Instead of leading with a succession of theoretical 'isms', the module structures its presentation of the subject around six teaching ‘blocks’, each of which explores a dilemma...... • Block 6: Continuity or change in global politics? Each block introduces new IR theories through discussions of the substantive dilemmas and adds in a layered way levels of analysis and conceptual complexity......., or dimension of variation. The dilemmas in question were chosen for the way they capture key themes in the field of International Studies (IR) as well as central aspects of the ‘international’ itself (ir). The six Blocks are: • Block 1: Co-operation or conflict? Introducing international relations • Block 2...

  12. Relational topology

    CERN Document Server

    Schmidt, Gunther

    2018-01-01

    This book introduces and develops new algebraic methods to work with relations, often conceived as Boolean matrices, and applies them to topology. Although these objects mirror the matrices that appear throughout mathematics, numerics, statistics, engineering, and elsewhere, the methods used to work with them are much less well known. In addition to their purely topological applications, the volume also details how the techniques may be successfully applied to spatial reasoning and to logics of computer science. Topologists will find several familiar concepts presented in a concise and algebraically manipulable form which is far more condensed than usual, but visualized via represented relations and thus readily graspable. This approach also offers the possibility of handling topological problems using proof assistants.

  13. Numerical relativity

    International Nuclear Information System (INIS)

    Piran, T.

    1982-01-01

    There are many recent developments in numerical relativity, but there remain important unsolved theoretical and practical problems. The author reviews existing numerical approaches to solution of the exact Einstein equations. A framework for classification and comparison of different numerical schemes is presented. Recent numerical codes are compared using this framework. The discussion focuses on new developments and on currently open questions, excluding a review of numerical techniques. (Auth.)

  14. Public relations

    International Nuclear Information System (INIS)

    1996-01-01

    At Nuclear Regulatory Authority of the Slovak Republic (NRA SR), the public relations belongs to the secretariat of the Chairman, and are a part of the policy of carefully planned and purposeful efforts to establish mutual relations between the authority and the public. A spokesmen of NRA SR is in charge of the public relations. The spokesman is ready, without a useless filibuster and based on a particular requirement, to inform governmental bodies, other national bodies and organizations, embassies and international organizations, the public and news media in case of an event at a nuclear installation. To provide for communications activities, NRA SR constructed and opened the Information centre with a particular equipment in autumn 1995, that has already started communications with some dailies, broadcasting, television and Press Agency SR. It has been envisaged that there will be press conferences held in the Information centre a few times a year, or NRA SR senior staff may be interviewed here on extraordinary events at NPPs, or on some other important occasions in NRA SR. In 1995, NRA Sr issued the Annual report in a few variants - each suitable for different use - on NRA SR activities and nuclear safety of Slovak nuclear power plants as of 1994. The NRA SR's Bulletin has started to be published with periodicity of 3 times a year, focusing on NRA SR activities both in Slovakia and abroad. NRA SR Information centre provides foreign visitors with independent propagation and information materials about the issue of nuclear safety enhancement at operational Slovak NPPs. Furthermore, the Information centre provides both the NRA SR's residences in Bratislava and Trnava with daily press monitoring of topical news

  15. Training Relations

    DEFF Research Database (Denmark)

    Smith, Aja

    This thesis explores the phenomenon of horse-assisted leadership training and the manners, in which the training relations between horses, managers and facilitators were entangled with perceptions of, what “proper sociality” entailed and felt like in contemporary Danish society. The study...... is positioned at the intersection of anthropology and consumer culture research and is based upon 15 months of ethnographic fieldwork in fields, offices and conference rooms throughout Denmark in 2012 and 2013 as well as reading of emic literature and marketing material. The main argument of the thesis is...

  16. Basic relativity

    CERN Document Server

    Mould, Richard A

    1994-01-01

    This comprehensive textbook develops in a logical and coherent way both the formalism and the physical ideas of special and general relativity. Part one focuses on the special theory and begins with the study of relativistic kinematics from three points of view. Part two begins with a chapter introducing differential geometry. Subsequent chapters cover: rotation, the electromagnetic field, and material media. A second chapter on differential geometry provides the background for Einstein's gravitational-field equation and Schwarzschild's solution. The book is aimed at advanced undergraduates and beginning graduate students in physics or astrophysics.

  17. Relatives and Relations in Paluai’

    DEFF Research Database (Denmark)

    Schokkin, Dineke; Otto, Ton

    2017-01-01

    This paper discusses the expression of kinship in Paluai (Baluan-Pam, ISO 639-3: blq), an Oceanic language spoken on Baluan Island, Manus Province, Papua New Guinea. Based on data gathered during extensive fieldwork, the authors first consider the formal characteristics of nominal possessive cons...... of birth order terms, which are a relatively rare phenomenon, and the partial replacement of the system by terms from the creole language Tok Pisin....

  18. Special relativity

    CERN Document Server

    Faraoni, Valerio

    2013-01-01

    This book offers an essential bridge between college-level introductions and advanced graduate-level books on special relativity. It begins at an elementary level, presenting and discussing the basic concepts normally covered in college-level works, including the Lorentz transformation. Subsequent chapters introduce the four-dimensional worldview implied by the Lorentz transformations, mixing time and space coordinates, before continuing on to the formalism of tensors, a topic usually avoided in lower-level courses. The book’s second half addresses a number of essential points, including the concept of causality; the equivalence between mass and energy, including applications; relativistic optics; and measurements and matter in Minkowski spacetime. The closing chapters focus on the energy-momentum tensor of a continuous distribution of mass-energy and its covariant conservation; angular momentum; a discussion of the scalar field of perfect fluids and the Maxwell field; and general coordinates. Every chapter...

  19. Community relations

    International Nuclear Information System (INIS)

    O'Neil, C.

    1997-01-01

    The interaction of the oil and gas companies with the Northern communities regarding drilling activities was an important aspect of oil and gas operations conducted in the Beaufort Sea. During the 1960s the industry and aboriginal people basically ignored each other. Later, the industry put more emphasis on community consultation until finally two-way communication was established. Respect for the land and the environment were very important to aboriginal people who depended on the land and its resources for their traditional way of life. Community relations policies by the various companies involved in the area, and the impact they have had on their respective communities were recounted. Not all efforts were successful, however, the companies and the communities learned from their experiences, and by the time operations ceased, the communities seemed to be more appreciative of the ways they were being treated by the oil companies. 22 figs

  20. Numerical relativity

    CERN Document Server

    Nakamura, T

    1993-01-01

    In GR13 we heard many reports on recent. progress as well as future plans of detection of gravitational waves. According to these reports (see the report of the workshop on the detection of gravitational waves by Paik in this volume), it is highly probable that the sensitivity of detectors such as laser interferometers and ultra low temperature resonant bars will reach the level of h ~ 10—21 by 1998. in this level we may expect the detection of the gravitational waves from astrophysical sources such as coalescing binary neutron stars once a year or so. Therefore the progress in numerical relativity is urgently required to predict the wave pattern and amplitude of the gravitational waves from realistic astrophysical sources. The time left for numerical relativists is only six years or so although there are so many difficulties in principle as well as in practice.

  1. International relations

    International Nuclear Information System (INIS)

    Anon.

    2009-01-01

    The French nuclear safety authority (A.S.N.) has participated at different meeting in European Union as nuclear decommissioning assistance programme(N.D.A.P.), Regulatory assistance management group (R.A.M.G.) and Instrument for nuclear safety cooperation (I.N.S.C.). The members of Western European nuclear regulator association (W.E.N.R.A.) met and discussed about the future of W.E.N.R.A. and its representativeness and its cooperation with European nuclear safety regulator group (E.N.S.R.E.G.) and head of European radiation control authorities (H.E.R.C.A.). About International relations it is to noticed a meeting at the invitation of IAEA to discuss about the possibility to resort to the Ines scale for medical events. An audit mission under the IAEA aegis stood at Fessenheim, O.S.A.R.T. for operational safety review team. Two years and a half passed by between the audit mission Integrated regulatory review service (I.R.S.S.) welcome by A.S.N. in november 2006 and the audit mission follow up in 2009, 12 experts from 11 different countries and coordinated by three representatives of IAEA worked, the conclusions were that 90% of recommendations made to A.S.N. in 2006 were treated in a satisfying way; the evaluation gives three new recommendations, 7 new suggestions and 11 new correct practices. A meeting of the commission on safety standards (C.S.S.) stood in april 2009. Some others meeting are to be noticed: nuclear safety and security group (N.S.S.G.), expert group on nuclear and radiation safety (E.G.N.R.S.) instituted by the council of the Baltic sea states (C.B.S.S.) treats data exchange on the national networks of dose rates and surveillance of radioactivity in air. International nuclear regulator association (I.N.R.A.) held its first meeting in april 2009 at Seoul (Korea). Bilateral relations with Poland, Italy, Ukraine and Germany planed cooperation or information exchange in the field of nuclear safety. Participation to conference in Usa, meetings with United

  2. Production of Geotrichum candidum polygalacturonases via solid state fermentation on grape pomace

    Czech Academy of Sciences Publication Activity Database

    Illková, K.; Zemková, Z.; Flodrová, Dana; Jäger, J.; Benkovská, Dagmar; Omelková, J.; Vadkertiová, R.; Bobálová, Janette; Stratilová, E.

    2012-01-01

    Roč. 66, č. 9 (2012), s. 852-860 ISSN 0366-6352 Institutional research plan: CEZ:AV0Z40310501 Keywords : geotrichum candidum * exopolygalacturonase * endopolygalacturonase Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.879, year: 2012

  3. Fungal polygalacturonase activity reflects susceptibility of carnation cultivars to Fusarium wilt

    NARCIS (Netherlands)

    Baayen, R.P.; Schoffelmeer, E.A.M.; Toet, S.; Elgersma, D.M.

    1997-01-01

    Carnation cultivars with different levels of partial resistance were inoculated with race 2 of Fusarium oxysporum f.sp. dianthi and monitored for accumulation of host phytoalexins, fungal escape from compartmentalization, production of fungal pectin-degrading enzymes and development of external

  4. Comprehensive glycan analysis of recombinant Aspergillus niger endo-polygalacturonase C.

    Science.gov (United States)

    Woosley, Bryan; Xie, Min; Wells, Lance; Orlando, Ron; Garrison, Derek; King, Daniel; Bergmann, Carl

    2006-07-01

    The enzyme PGC is produced by the fungus Aspergillus niger during invasion of plant cell walls. The enzyme has been homologously overexpressed to provide sufficient quantities of purified enzyme for biological studies. We have characterized this enzyme in terms of its posttranslational modifications (PTMs) and found it to be both N- and O-glycosylated. The glycosyl moieties have also been characterized. This has involved a combination of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF), liquid chromatography (LC)-ion trap, and LC-electrospray ionization (ESI) mass spectrometries in conjunction with trypsin degradation and beta-elimination, followed by Michael addition with dithiothreitol (BEMAD). This is the first demonstration of the ability of BEMAD to map glycosylation sites other than O-GlcNAc sites. The complete characterization of all PTMs on PGC allows us to model them on the peptide backbone, revealing potential roles played by the glycans in modulating the interaction of the enzyme with other macromolecules.

  5. Study of the mode of action of a polygalacturonase from the phytopathogen Burkholderia cepacia

    DEFF Research Database (Denmark)

    Massa, C.; Clausen, Mads Hartvig; Stojan, J.

    2007-01-01

    We have recently isolated and heterologously expressed BcPeh28A, an endopolygalacturonase from the phytopathogenic Gram-negative bacterium Burkholderia cepacia. Endopolygalacturonases belong to glycoside hydrolase family 28 and are responsible for the hydrolysis of the non-esterified regions...

  6. Targeted Modification of Homogalacturonan by Transgenic Expression of a Fungal Polygalacturonase Alters Plant Growth1

    Science.gov (United States)

    Capodicasa, Cristina; Vairo, Donatella; Zabotina, Olga; McCartney, Lesley; Caprari, Claudio; Mattei, Benedetta; Manfredini, Cinzia; Aracri, Benedetto; Benen, Jacques; Knox, J. Paul; De Lorenzo, Giulia; Cervone, Felice

    2004-01-01

    Pectins are a highly complex family of cell wall polysaccharides comprised of homogalacturonan (HGA), rhamnogalacturonan I and rhamnogalacturonan II. We have specifically modified HGA in both tobacco (Nicotiana tabacum) and Arabidopsis by expressing the endopolygalacturonase II of Aspergillus niger (AnPGII). Cell walls of transgenic tobacco plants showed a 25% reduction in GalUA content as compared with the wild type and a reduced content of deesterified HGA as detected by antibody labeling. Neutral sugars remained unchanged apart from a slight increase of Rha, Ara, and Gal. Both transgenic tobacco and Arabidopsis were dwarfed, indicating that unesterified HGA is a critical factor for plant cell growth. The dwarf phenotypes were associated with AnPGII activity as demonstrated by the observation that the mutant phenotype of tobacco was completely reverted by crossing the dwarfed plants with plants expressing PGIP2, a strong inhibitor of AnPGII. The mutant phenotype in Arabidopsis did not appear when transformation was performed with a gene encoding AnPGII inactivated by site directed mutagenesis. PMID:15247378

  7. Social relations: network, support and relational strain

    DEFF Research Database (Denmark)

    Due, P; Holstein, B; Lund, Rikke

    1999-01-01

    We introduce a conceptual framework with social relations as the main concept and the structure and the function of social relations as subconcepts. The structure of social relations covers aspects of formal relations and social network. The function of social relations covers social support......,011. The postal questionnaires were answered by a random sample in each of the age groups. The results show marked age and gender differences in both the structure and the function of social relations. The social network, measured as weekly contacts, weakens with age and so does instrumental support. Emotional...... support is unrelated to this decline in contact frequency and appears to be at the same level for younger and older individuals. Relational strain, measured as conflicts, declines with age for all kinds of social relations. The weakening of the social network with age does not seem to affect the level...

  8. Incorporating Relation Paths in Neural Relation Extraction

    OpenAIRE

    Zeng, Wenyuan; Lin, Yankai; Liu, Zhiyuan; Sun, Maosong

    2016-01-01

    Distantly supervised relation extraction has been widely used to find novel relational facts from plain text. To predict the relation between a pair of two target entities, existing methods solely rely on those direct sentences containing both entities. In fact, there are also many sentences containing only one of the target entities, which provide rich and useful information for relation extraction. To address this issue, we build inference chains between two target entities via intermediate...

  9. Visualizing relativity: The OpenRelativity project

    Science.gov (United States)

    Sherin, Zachary W.; Cheu, Ryan; Tan, Philip; Kortemeyer, Gerd

    2016-05-01

    We present OpenRelativity, an open-source toolkit to simulate effects of special relativity within the popular Unity game engine. Intended for game developers, educators, and anyone interested in physics, OpenRelativity can help people create, test, and share experiments to explore the effects of special relativity. We describe the underlying physics and some of the implementation details of this toolset with the hope that engaging games and interactive relativistic "laboratory" experiments might be implemented.

  10. What Are Related Disorders?

    Science.gov (United States)

    ... The Marfan Foundation Marfan & Related Disorders What is Marfan Syndrome? What are Related Disorders? What are the Signs? ... Contact Us Donate Marfan & Related Disorders What is Marfan Syndrome? What are Related Disorders? What are the Signs? ...

  11. Tests Related to Pregnancy

    Science.gov (United States)

    ... to learn. Search form Search Tests related to pregnancy You are here Home Testing & Services Testing for ... to Genetic Counseling . What Are Tests Related to Pregnancy? Pregnancy related testing is done before or during ...

  12. Pioneers as Relational Subjects? Probing Relationality as ...

    African Journals Online (AJOL)

    relational engagement roles in driving the energy transition, as described on their website. ... He comments, 'In Japan, they call it Viking leadership,' .... island, such as the mayor, representatives of different business, leading employees at the.

  13. Public Relations and Marketing.

    Science.gov (United States)

    Savage, Daniel D.

    1987-01-01

    Urges community colleges to adopt pro-active public relations strategies. Examines the role of the public information officer in such areas as coordination of public relations and marketing activities, relations with media, and the development of a comprehensive public relations plan. (AYC)

  14. Functional Programming With Relations

    OpenAIRE

    Hutton, Graham

    1991-01-01

    While programming in a relational framework has much to offer over the functional style in terms of expressiveness, computing with relations is less efficient, and more semantically troublesome. In this paper we propose a novel blend of the functional and relational styles. We identify a class of "causal relations", which inherit some of the bi-directionality properties of relations, but retain the efficiency and semantic foundations of the functional style.

  15. Introduction to relation algebras relation algebras

    CERN Document Server

    Givant, Steven

    2017-01-01

    The first volume of a pair that charts relation algebras from novice to expert level, this text offers a comprehensive grounding for readers new to the topic. Upon completing this introduction, mathematics students may delve into areas of active research by progressing to the second volume, Advanced Topics in Relation Algebras; computer scientists, philosophers, and beyond will be equipped to apply these tools in their own field. The careful presentation establishes first the arithmetic of relation algebras, providing ample motivation and examples, then proceeds primarily on the basis of algebraic constructions: subalgebras, homomorphisms, quotient algebras, and direct products. Each chapter ends with a historical section and a substantial number of exercises. The only formal prerequisite is a background in abstract algebra and some mathematical maturity, though the reader will also benefit from familiarity with Boolean algebra and naïve set theory. The measured pace and outstanding clarity are particularly ...

  16. Theoretical general relativity: 1979

    International Nuclear Information System (INIS)

    Bergmann, O.

    1979-01-01

    The metric and field equations of Einstein's general relativity theory are written down. Solutions to the equations are discussed. Connection is made between relativity theory and elementary particle theory. Possibilities for a unified field theory are considered

  17. Relativity simply explained

    CERN Document Server

    Gardner, Martin

    2012-01-01

    Since the publication of Einstein's Special Theory of Relativity in 1905, the discovery of such astronomical phenomena as quasars, pulsars, and black holes - all intimately connected to relativity - has provoked a tremendous upsurge of interest in the subject. This volume, a revised version of Martin Gardner's earlier Relativity for the Million, brings this fascinating topic up to date. Witty, perceptive, and easily accessible to the general reader, it is one of the clearest and most entertaining introductions to relativity ever written.

  18. Nothing but relativity

    International Nuclear Information System (INIS)

    Pal, Palash B

    2003-01-01

    We deduce the most general space-time transformation laws consistent with the principle of relativity. Thus, our result contains the results of both Galilean and Einsteinian relativity. The velocity addition law comes as a by-product of this analysis. We also argue why Galilean and Einsteinian versions are the only possible embodiments of the principle of relativity

  19. Transit labor relations guide

    Science.gov (United States)

    2001-09-01

    This report is designed as a guide for those involved in labor relations in the transit industry. It begins with a history of transit labor relations. The economic, political, and legal environment of transit relations is then discussed. A section fo...

  20. Relativity and cosmology

    CERN Document Server

    Kaufmann, William J

    1973-01-01

    The foundations of gravitational theory ; the birth of relativity theory ; the foundations of general relativity ; experimental tests of relativity ; the meaning of the redshift ; the black hole ; wormholes and white holes ; galaxies and quasars ; gravitational waves ; the shape of the Universe ; the creation of the Universe.

  1. A Bigraph Relational Model

    DEFF Research Database (Denmark)

    Beauquier, Maxime; Schürmann, Carsten

    2011-01-01

    In this paper, we present a model based on relations for bigraphical reactive system [Milner09]. Its defining characteristics are that validity and reaction relations are captured as traces in a multi-set rewriting system. The relational model is derived from Milner's graphical definition...

  2. Rayleigh reciprocity relations: Applications

    International Nuclear Information System (INIS)

    Lin Ju; Li Xiao-Lei; Wang Ning

    2016-01-01

    Classical reciprocity relations have wide applications in acoustics, from field representation to generalized optical theorem. In this paper we introduce our recent results on the applications and generalization of classical Rayleigh reciprocity relation: higher derivative reciprocity relations as a generalization of the classical one and a theoretical proof on the Green’s function retrieval from volume noises. (special topic)

  3. Elements of relativity theory

    International Nuclear Information System (INIS)

    Lawden, D.F.

    1985-01-01

    The book on elements of relativity theory is intended for final year school students or as an early university course in mathematical physics. Special principle of relativity, lorentz transformation, velocity transformations, relativistic mechanics, and general theory of relativity, are all discussed. (U.K.)

  4. Relativity theory and gravitation

    International Nuclear Information System (INIS)

    Bondi, H.

    1986-01-01

    The paper on relativity theory and gravitation is presented as a preface to the first of the articles submitted to the Journal on general relativity. Newtonian gravitation and and observation, relativity, and the sources of the gravitational field, are all discussed. (UK)

  5. Decreasing Relative Risk Premium

    DEFF Research Database (Denmark)

    Hansen, Frank

    relative risk premium in the small implies decreasing relative risk premium in the large, and decreasing relative risk premium everywhere implies risk aversion. We finally show that preferences with decreasing relative risk premium may be equivalently expressed in terms of certain preferences on risky......We consider the risk premium demanded by a decision maker with wealth x in order to be indifferent between obtaining a new level of wealth y1 with certainty, or to participate in a lottery which either results in unchanged present wealth or a level of wealth y2 > y1. We define the relative risk...... premium as the quotient between the risk premium and the increase in wealth y1–x which the decision maker puts on the line by choosing the lottery in place of receiving y1 with certainty. We study preferences such that the relative risk premium is a decreasing function of present wealth, and we determine...

  6. Relational aggression in marriage.

    Science.gov (United States)

    Carroll, Jason S; Nelson, David A; Yorgason, Jeremy B; Harper, James M; Ashton, Ruth Hagmann; Jensen, Alexander C

    2010-01-01

    Drawing from developmental theories of relational aggression, this article reports on a study designed to identify if spouses use relationally aggressive tactics when dealing with conflict in their marriage and the association of these behaviors with marital outcomes. Using a sample of 336 married couples (672 spouses), results revealed that the majority of couples reported that relationally aggressive behaviors, such as social sabotage and love withdrawal, were a part of their marital dynamics, at least to some degree. Gender comparisons of partner reports of their spouse's behavior revealed that wives were significantly more likely to be relationally aggressive than husbands. Structural equation modeling demonstrated that relational aggression is associated with lower levels of marital quality and greater marital instability for both husbands and wives. Implications are drawn for the use of relational aggression theory in the future study of couple conflict and marital aggression. (c) 2010 Wiley-Liss, Inc.

  7. Strategi Komunikasi Public Relations

    OpenAIRE

    Artis, Artis

    2011-01-01

    Living man in interrelates society. Relationship among human being done by gets communication so man one by another one mutually understand and influence regard for the benefit, it that always been practiced by Public Relations( liaison) in a governance and also firm institute to reach to the effect which ices. The institute of Public Relations declares for,”Public Relations is overall effort which be passed off by design and berkesenambungan in order to creates and pet keenness and mutual un...

  8. Relative Thinking Theory

    OpenAIRE

    Ofer H. Azar

    2005-01-01

    The article presents a theory that I denote “Relative Thinking Theory,” which claims that people consider relative differences and not only absolute differences when making various economics decisions, even in those cases where the rational model dictates that people should consider only absolute differences. The article reviews experimental evidence for this behavior, summarizing briefly several experiments I conducted, as well as some earlier related literature. It then discusses how we can...

  9. Motion and relativity

    CERN Document Server

    Infeld, Leopold

    1960-01-01

    Motion and Relativity focuses on the methodologies, solutions, and approaches involved in the study of motion and relativity, including the general relativity theory, gravitation, and approximation.The publication first offers information on notation and gravitational interaction and the general theory of motion. Discussions focus on the notation of the general relativity theory, field values on the world-lines, general statement of the physical problem, Newton's theory of gravitation, and forms for the equation of motion of the second kind. The text then takes a look at the approximation meth

  10. Public relations and ethics

    Directory of Open Access Journals (Sweden)

    Bajić Milan

    2010-01-01

    Full Text Available The aim of this paper is the analysis of different forms of PR implementation and research its relation with ethics in practice. 'Public relations' is the every-day term that represents the job that is widely used in all aspects of life and work in today's society. Public relations represent a specific form of communication that has a particular application in society. Public relations involve focusing on a public aspect of organization with the aim of building a positive attitude and image. Image of public relations as a profession is often unfairly negative, and the reason for this is unprofessional and unethical relation of individuals towards their profession. In practice ethics in public relations is often considered to be an oxymoron. Ethical thinking of experts in public relations goes from Biblical attitude 'all you want people to do to you, do even so to them' (Matthew 7:12to professional loyalty to organization they work for. Because of unethical appearance it is important to set the rules, in the form of codex by which the public relations professionals will set their behaviors. .

  11. Gaining Relational Competitive Advantages

    DEFF Research Database (Denmark)

    Hu, Yimei; Zhang, Si; Li, Jizhen

    2015-01-01

    Establishing strategic technological partnerships (STPs) with foreign partners is an increasingly studied topic within the innovation management literature. Partnering firms can jointly create sources of relational competitive advantage. Chinese firms often lack research and development (R......&D) capabilities but are increasingly becoming preferred technological partners for transnational corporations. We investigate an STP between a Scandinavian and a Chinese firm and try to explore how to gain relational competitive advantage by focusing on its two essential stages: relational rent generation...... and appropriation. Based on an explorative case study, we develop a conceptual framework that consists of process, organizational alliance factors, and coordination modes that we propose lead to relational competitive advantage....

  12. Models as Relational Categories

    Science.gov (United States)

    Kokkonen, Tommi

    2017-11-01

    Model-based learning (MBL) has an established position within science education. It has been found to enhance conceptual understanding and provide a way for engaging students in authentic scientific activity. Despite ample research, few studies have examined the cognitive processes regarding learning scientific concepts within MBL. On the other hand, recent research within cognitive science has examined the learning of so-called relational categories. Relational categories are categories whose membership is determined on the basis of the common relational structure. In this theoretical paper, I argue that viewing models as relational categories provides a well-motivated cognitive basis for MBL. I discuss the different roles of models and modeling within MBL (using ready-made models, constructive modeling, and generative modeling) and discern the related cognitive aspects brought forward by the reinterpretation of models as relational categories. I will argue that relational knowledge is vital in learning novel models and in the transfer of learning. Moreover, relational knowledge underlies the coherent, hierarchical knowledge of experts. Lastly, I will examine how the format of external representations may affect the learning of models and the relevant relations. The nature of the learning mechanisms underlying students' mental representations of models is an interesting open question to be examined. Furthermore, the ways in which the expert-like knowledge develops and how to best support it is in need of more research. The discussion and conceptualization of models as relational categories allows discerning students' mental representations of models in terms of evolving relational structures in greater detail than previously done.

  13. Relational Perspectives on Leading

    DEFF Research Database (Denmark)

    Relational Perspectives on Leading discusses leadership from a relational and social constructionism perspective as practiced on an everyday basis between people. The book pursues a fast growing, practice-based approach - particularly within the Anglo-Saxon parts of the world - to organization...

  14. EU-Mashreq Relations

    DEFF Research Database (Denmark)

    Seeberg, Peter

    2018-01-01

    -related foreign policy considerations: the ENP Action Plans (APs) ‘will draw on a common set of principles but will be differentiated, reflecting the existing state of relations with each country, its needs and capacities, as well as common interests’ (Commission of the European Communities 2004). In the Mashreq...

  15. Annoying Danish Relatives

    DEFF Research Database (Denmark)

    Jensen de López, Kristine M.; Sundahl Olsen, Lone; Chondrigianni, V.

    2014-01-01

    This study examines the comprehension and production of subject and object relative clauses (SRCs, ORCs) by children with Specific Language Impairment (SLI) and their typically developing (TD) peers. The purpose is to investigate whether relative clauses are problematic for Danish children with S...... with the assignment of thematic roles rather than with the structural make-up of RCs....

  16. Destination: Alumni Relations

    Science.gov (United States)

    Scully, Maura King

    2010-01-01

    Increasingly today, with the growing and sophisticated skill set alumni professionals need to get the job done, alumni relations has become a destination career rather than a stop along the way. Modern alumni relations is "so much more than homecoming and punch-and-cookie receptions." It's marketing, volunteer management, and social networking. To…

  17. Heat-Related Illnesses

    Science.gov (United States)

    ... Share this! EmergencyCareForYou » Emergency 101 » Heat-Related Illnesses Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

  18. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Share this! EmergencyCareForYou » Emergency 101 » Heat-Related Illnesses Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

  19. Teaching Mediated Public Relations.

    Science.gov (United States)

    Kent, Michael L.

    2001-01-01

    Discusses approaches to teaching a mediated public relations course, emphasizing the World Wide Web. Outlines five course objectives, assignments and activities, evaluation, texts, and lecture topics. Argues that students mastering these course objectives will understand ethical issues relating to media use, using mediated technology in public…

  20. Measuring Relational Reasoning

    Science.gov (United States)

    Alexander, Patricia A.; Dumas, Denis; Grossnickle, Emily M.; List, Alexandra; Firetto, Carla M.

    2016-01-01

    Relational reasoning is the foundational cognitive ability to discern meaningful patterns within an informational stream, but its reliable and valid measurement remains problematic. In this investigation, the measurement of relational reasoning unfolded in three stages. Stage 1 entailed the establishment of a research-based conceptualization of…

  1. Relative Effects at Work

    NARCIS (Netherlands)

    Braeken, Johan; Mulder, Joris; Wood, Stephen

    2015-01-01

    Assessing the relative importance of predictors has been of historical importance in a variety of disciplines including management, medicine, economics, and psychology. When approaching hypotheses on the relative ordering of the magnitude of predicted effects (e.g., the effects of discrimination

  2. Methods of numerical relativity

    International Nuclear Information System (INIS)

    Piran, T.

    1983-01-01

    Numerical Relativity is an alternative to analytical methods for obtaining solutions for Einstein equations. Numerical methods are particularly useful for studying generation of gravitational radiation by potential strong sources. The author reviews the analytical background, the numerical analysis aspects and techniques and some of the difficulties involved in numerical relativity. (Auth.)

  3. Relational Processing Following Stroke

    Science.gov (United States)

    Andrews, Glenda; Halford, Graeme S.; Shum, David; Maujean, Annick; Chappell, Mark; Birney, Damian

    2013-01-01

    The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three…

  4. The Redshifts in Relativity

    Science.gov (United States)

    Singh, Satya Pal; Singh, Apoorva; Hareet, Prabhav

    2011-01-01

    The progress of modern cosmology took off in 1917 when A. Einstein published his paper on general theory of relativity extending his work of special theory of relativity (1905). In 1922 Alexander Friedmann constructed a mathematical model for expanding Universe that had a big bang in remote past. The experimental evidences could come in 1929 by…

  5. Forces in General Relativity

    Science.gov (United States)

    Ridgely, Charles T.

    2010-01-01

    Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…

  6. Antecedents of Relational Capital

    DEFF Research Database (Denmark)

    Nowinska, Agnieszka

    This paper merges economic geography and relational capital perspective in order to analyze the proximity-based antecedents of relational assets in brokerage. It investigates empirically the role and interplay of geographical and cognitive proximity between a broker and her buyers in a quantitative...... for buyers characteristics. Lastly, I make use the under-researched empirical field of brokers....

  7. Journalism of Relation

    DEFF Research Database (Denmark)

    Blaagaard, Bolette

    of cosmopolitanism from universal reproductions of sameness into creative productions of singular self-other relations based on the practiced and productive journalism. This is substantiated through case study analyses. The aim is to challenge the modern, rational journalistic subject referring back to the unified...... of the self-other relation which is simultaneously personal and political. Secondly, the dissertation relates the phenomenological ‘race’ and gender debates to the societal and productive context of contemporary European and ‘western’ globalised and mediated culture and politics. Journalism is re...... accountability and relation from journalistic training and practices whereby a ‘white’ and homogeneous social imaginary is reproduced. I make a call for thinking about journalism as relation – in terms of technological mediations, but also in terms of subjectivities. In order to allow for this, a shift is needed...

  8. Relative Lyapunov Center Bifurcations

    DEFF Research Database (Denmark)

    Wulff, Claudia; Schilder, Frank

    2014-01-01

    Relative equilibria (REs) and relative periodic orbits (RPOs) are ubiquitous in symmetric Hamiltonian systems and occur, for example, in celestial mechanics, molecular dynamics, and rigid body motion. REs are equilibria, and RPOs are periodic orbits of the symmetry reduced system. Relative Lyapunov...... center bifurcations are bifurcations of RPOs from REs corresponding to Lyapunov center bifurcations of the symmetry reduced dynamics. In this paper we first prove a relative Lyapunov center theorem by combining recent results on the persistence of RPOs in Hamiltonian systems with a symmetric Lyapunov...... center theorem of Montaldi, Roberts, and Stewart. We then develop numerical methods for the detection of relative Lyapunov center bifurcations along branches of RPOs and for their computation. We apply our methods to Lagrangian REs of the N-body problem....

  9. Utilization of wheat bran for enhanced production of exo-polygalacturonase by penicillium notatum using response surface methodology

    International Nuclear Information System (INIS)

    Bhatti, F.A.; Bhatti, I.A.; Asgher, M.

    2013-01-01

    Response surface methodology (RSM) has been one of the most commonly used optimization method in the recent years. Especially this technique is frequently used in the enzyme biotechnology. In this context Penicillium notatum was evaluated for enhanced biosynthesis of exo-polygalacturonse using statistical approach under solid state fermentation (SSF). Nine parameters were assessed for maximum biosynthesis of the enzyme using classical method (data not shown). Four factors (3 numerical and 1 categorical factor) were evaluated as the best having the influential effect on enzyme yield. These factors were incubation time (days), temperature (degree C), pH, and nitrogen sources. Nitrogen sources like glycine and ammonium chloride, were selected in RSM optimization as they were found to be the most promising in multiplying the exo-polygalacturonse activity during the classical approach. Maximum activity of the enzyme achieved was 1129.62 U/gds with incubation period 3 days, pH 1.318, temperature 30 degree C and using ammonium chloride as nitrogen source. All the experiments were performed at 40 % (V/W) moisture level using 10 g of wheat bran as substrate. An increase of 5.5 folds of activity was observed using this technique as compared to classical method. The results indicated that RSM could be used to get enhanced activities of exo-polygalacturonse under SSF. (author)

  10. Genomic characterization of plant cell wall degrading enzymes and in silico analysis of xylanses and polygalacturonases of Fusarium virguliforme

    Science.gov (United States)

    Plant cell wall degrading enzymes (PCWDEs) are important effectors for plant pathogens to invade plants. In this study, the composition of PCWDEs in Fusarium virguliforme that were grown for 5-days and 20 days in liquid medium was determined by RNA-Seq. Differential expression analysis showed more P...

  11. Ether formulations of relativity

    International Nuclear Information System (INIS)

    Duffy, M.C.

    1980-01-01

    Contemporary ether theories are surveyed and criticised, especially those formally identical to orthodox Relativity. The historical development of Relativity, Special and General, in terms of an ether, is briefly indicated. Classical interpretations of Generalized Relativity using ether are compared to Euclidean formulations using a background space. The history of a sub-group of theories, formulating a 'new' Relativity involving modified transforms, is outlined. According to the theory with which they agree, recent supposed detections of drift are classified and criticised. Cosmological evidence suggesting an ether is mentioned. Only ether theories formally identical to Relativity have been published in depth. They stand criticised as being contrary to the positivist spirit. The history of mechanical analogues is traced, from Hartley's representing gravitating matter as spherical standing waves, to recent suggestions that vortex-sponge might model electromagnetic, quantum, uncertainty and faster-than-light phenomena. Contemporary theories are particular physical theories, themselves 'second interpretations' of a primary mathematical model. Mechanical analogues are auxiliary, not necessary, to other theory, disclosing relationships between classical and non-classical descriptions of assemblies charging state. The ether-relativity polemic, part of a broader dispute about relativity, is founded on mistaken conceptions of the roles of mathematical and physical models, mechanical analogues; and a distored view of history, which indicates that ether theories have become relativistic. (author)

  12. Modernization of credit relations

    Directory of Open Access Journals (Sweden)

    S.V. Volosovich

    2015-03-01

    Full Text Available Nowadays it is essential to modernize credit relations in the conditions of global economy transformations. This is due to the influence of integration processes on credit relations and transformation of the risks inherent in the credit field. The purpose of this article is to develop measures that help to improve the efficiency of interaction of credit relations’ participants. Modernization of credit relations is based on the interaction of its main and indirect subjects who belong to the subsystems of loans granting, deposits attraction and provision of related services. Its goal is to pass from extensive to intensive model of interaction between the subjects of credit relations. Components of the credit relations modernization are the following: institutional modernization, which is based on the interaction of credit relations’ subjects, and ensures the development of competition in all credit market’s segments, the creation of its corresponding infrastructure, qualitative change in the approaches of regulation and supervision; technological modernization, which involves the formation of joint products on the credit market and the formation of an integrated informational and analytical system. In the result of the credit relations’ modernization it is expected to achieve synergies between the subjects of credit relations, that will lead to changes in the business architecture of the financial market.

  13. The relational universe

    International Nuclear Information System (INIS)

    Magnon, A.

    1998-01-01

    A relational approach to be observable universe is proposed, which precludes the concept of absolute background. Space-time events emerge as dynamical entities which owe their existence to a memorization process, itself inter wind with the availability of cosmological horizons (screening from totality) sourcing long-range correlations. The resulting (and relational) mode of description sheds light on various paradoxes (EPR, Foucault pendolum, light beam effect, etc.), on the problem of instantaneous and global influences (quark deconfinement) as related to the interconnectedness of our cosmos. This scenario leads to comment on living systems vs. robots, and on non-recursive and global aspects of the mathematical intuition

  14. Special theory of relativity

    CERN Document Server

    Kilmister, Clive William

    1970-01-01

    Special Theory of Relativity provides a discussion of the special theory of relativity. Special relativity is not, like other scientific theories, a statement about the matter that forms the physical world, but has the form of a condition that the explicit physical theories must satisfy. It is thus a form of description, playing to some extent the role of the grammar of physics, prescribing which combinations of theoretical statements are admissible as descriptions of the physical world. Thus, to describe it, one needs also to describe those specific theories and to say how much they are limit

  15. Gravitation and relativity

    CERN Document Server

    Hoffmann, William F

    1964-01-01

    Remarks on the observational basis of general relativity ; Riemannian geometry ; gravitation as geometry ; gravitational waves ; Mach's principle and experiments on mass anisotropy ; the many faces of Mach ; the significance for the solar system of time-varying gravitation ; relativity principles and the role of coordinates in physics ; the superdense star and the critical nucleon number ; gravitation and light ; possible effects on the solar system of φ waves if they exist ; the Lyttleton-Bondi universe and charge equality ; quantization of general relativity ; Mach's principle as boundary condition for Einstein's equations.

  16. NgsRelate

    DEFF Research Database (Denmark)

    Korneliussen, Thorfinn Sand; Moltke, Ida

    2015-01-01

    . Using both simulated and real data, we show that NgsRelate provides markedly better estimates for low-depth NGS data than two state-of-the-art genotype-based methods. AVAILABILITY: NgsRelate is implemented in C++ and is available under the GNU license at www.pop gen.dk/software. CONTACT: ida...... be called with high certainty. RESULTS: We present a software tool, NgsRelate, for estimating pairwise relatedness from NGS data. It provides maximum likelihood estimates that are based on genotype likelihoods instead of genotypes and thereby takes the inherent uncertainty of the genotypes into account...

  17. Clocks and special relativity

    International Nuclear Information System (INIS)

    MacRoberts, D.T.

    1980-01-01

    A kinematic theory without precise definitions of the 'space' and 'time' used is an uninterpreted calculus. The definition of 'time' in special relativity is based on light propagation and the 'constant velocity of light' is a tautological consequence of the definition. When this definition is reified in a 'clock' the phenomenon of 'time dilation' occurs, in terms of the defined time, but is not reciprocal between moving systems; the postulate of relativity is not observed. The new definition of time is compatible with an ether theory without the relativity principle. The derivation of the Lorentz transformations, which requires both postulates, is purely formalistic and is not ontologically sound. (Auth.)

  18. Public Relations vs. Propaganda

    Directory of Open Access Journals (Sweden)

    Alexandru BASTIAN

    2006-10-01

    Full Text Available The paper aims at presenting the characteristics, methods and aplications of two related activities – Public Relations and propaganda. Although different from the piont of wiev of purpose and results (the practice of Public Relations aims at establishing and maintaining mutual lines of communications, understanding, acceptance, and cooperation between an organization and its publics, through transparency and honesty, while propaganda insists on a message that is intended primarily to serve the interests of the messenger. in order to influence public opinion and to manipulate other people’s beliefs by any means necessary, the two activities also present quite a lot of similarities.

  19. Simple relation algebras

    CERN Document Server

    Givant, Steven

    2017-01-01

    This monograph details several different methods for constructing simple relation algebras, many of which are new with this book. By drawing these seemingly different methods together, all are shown to be aspects of one general approach, for which several applications are given. These tools for constructing and analyzing relation algebras are of particular interest to mathematicians working in logic, algebraic logic, or universal algebra, but will also appeal to philosophers and theoretical computer scientists working in fields that use mathematics. The book is written with a broad audience in mind and features a careful, pedagogical approach; an appendix contains the requisite background material in relation algebras. Over 400 exercises provide ample opportunities to engage with the material, making this a monograph equally appropriate for use in a special topics course or for independent study. Readers interested in pursuing an extended background study of relation algebras will find a comprehensive treatme...

  20. General Relativity and Energy

    Science.gov (United States)

    Jackson, A. T.

    1973-01-01

    Reviews theoretical and experimental fundamentals of Einstein's theory of general relativity. Indicates that recent development of the theory of the continually expanding universe may lead to revision of the space-time continuum of the finite and unbounded universe. (CC)

  1. General relativity and experiment

    OpenAIRE

    Damour, T.

    1994-01-01

    The confrontation between Einstein's theory of gravitation and experiment is summarized. Although all current experimental data are compatible with general relativity, the importance of pursuing the quest for possible deviations from Einstein's theory is emphasized.

  2. Sport-related concussions

    Directory of Open Access Journals (Sweden)

    Jéssica Natuline Ianof

    Full Text Available ABSTRACT Traumatic brain injury (TBI is a major cause of lifelong disability and death worldwide. Sport-related traumatic brain injury is an important public health concern. The purpose of this review was to highlight the importance of sport-related concussions. Concussion refers to a transient alteration in consciousness induced by external biomechanical forces transmitted directly or indirectly to the brain. It is a common, although most likely underreported, condition. Contact sports such as American football, rugby, soccer, boxing, basketball and hockey are associated with a relatively high prevalence of concussion. Various factors may be associated with a greater risk of sport-related concussion, such as age, sex, sport played, level of sport played and equipment used. Physical complaints (headache, fatigue, dizziness, behavioral changes (depression, anxiety, irritability and cognitive impairment are very common after a concussion. The risk of premature return to activities includes the prolongation of post-concussive symptoms and increased risk of concussion recurrence.

  3. Relativity of Visual Communication

    Directory of Open Access Journals (Sweden)

    Arto Mutanen

    2016-03-01

    Full Text Available Communication is sharing and conveying information. In visual communication especially visual messages have to be formulated and interpreted. The interpretation is relative to a method of information presentation method which is human construction. This holds also in the case of visual languages. The notions of syntax and semantics for visual languages are not so well founded as they are for natural languages. Visual languages are both syntactically and semantically dense. The density is connected to the compositionality of the (pictorial languages. In the paper Charles Sanders Peirce’s theory of signs will be used in characterizing visual languages. This allows us to relate visual languages to natural languages. The foundation of information presentation methods for visual languages is the logic of perception, but only if perception is understood as propositional perception. This allows us to understand better the relativity of information presentation methods, and hence to evaluate the cultural relativity of visual communication.

  4. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Your Wishes Visiting The ER Who Takes Care Of You In An Emergency? Checking Into ... Illnesses Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can be ...

  5. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Health System in Chesterfield, Missouri Heat-related illness can be caused by overexposure to the sun or ... the elderly are most at risk, but anyone can be affected. Here you will find information about ...

  6. Publicity and public relations

    Science.gov (United States)

    Fosha, Charles E.

    1990-01-01

    This paper addresses approaches to using publicity and public relations to meet the goals of the NASA Space Grant College. Methods universities and colleges can use to publicize space activities are presented.

  7. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... ICE” in Your Cell Phone Prepare for Disasters Communication With Your Family And Your Doctor About Your ... Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can be ...

  8. Relativity in modern physics

    CERN Document Server

    Deruelle, Nathalie

    2018-01-01

    This comprehensive textbook on relativity integrates Newtonian physics, special relativity and general relativity into a single book that emphasizes the deep underlying principles common to them all, yet explains how they are applied in different ways in these three contexts. Newton's ideas about how to represent space and time, his laws of dynamics, and his theory of gravitation established the conceptual foundation from which modern physics developed. Book I in this volume offers undergraduates a modern view of Newtonian theory, emphasizing those aspects needed for understanding quantum and relativistic contemporary physics. In 1905, Albert Einstein proposed a novel representation of space and time, special relativity. Book II presents relativistic dynamics in inertial and accelerated frames, as well as a detailed overview of Maxwell's theory of electromagnetism. This provides undergraduate and graduate students with the background necessary for studying particle and accelerator physics, astrophysics and ...

  9. Relating BIP and Reo

    NARCIS (Netherlands)

    K.P.C. Dokter (Kasper); S.-S.T.Q. Jongmans (Sung-Shik); F. Arbab (Farhad); S. Bliudze (Simon)

    2015-01-01

    textabstractCoordination languages simplify design and development of concurrent systems. Particularly, exogenous coordination languages, like BIP and Reo, enable system designers to express the interactions among components in a system explicitly. In this paper we establish a formal relation

  10. Relating BIP and Reo

    NARCIS (Netherlands)

    K.P.C. Dokter (Kasper); S.-S.T.Q. Jongmans (Sung-Shik); F. Arbab (Farhad); S. Bliudze (Simon); S. Knight; I. Lanese; A. Lluch Lafuente; H.T. Vieira

    2015-01-01

    htmlabstractCoordination languages simplify design and development of concurrent systems. Particularly, exogenous coordination languages, like BIP and Reo, enable system designers to express the interactions among components in a system explicitly. In this paper we establish a formal relation

  11. de Sitter special relativity

    International Nuclear Information System (INIS)

    Aldrovandi, R; Almeida, J P Beltran; Pereira, J G

    2007-01-01

    A special relativity based on the de Sitter group is introduced, which is a theory that might hold up in the presence of a non-vanishing cosmological constant. Like ordinary special relativity, it retains the quotient character of spacetime, and a notion of homogeneity. As a consequence, the underlying spacetime will be a de Sitter spacetime, whose associated kinematics will differ from that of ordinary special relativity. The corresponding modified notions of energy and momentum are obtained, and the exact relationship between them, which is invariant under a re-scaling of the involved quantities, explicitly exhibited. Since the de Sitter group can be considered a particular deformation of the Poincare group, this theory turns out to be a specific kind of deformed (or doubly) special relativity. Some experimental consequences, as well as the causal structure of spacetime-modified by the presence of the de Sitter horizon-are briefly discussed

  12. Asbestos-related malignancy

    International Nuclear Information System (INIS)

    Antmann, K.; Aisner, J.

    1986-01-01

    This book contains 20 chapters. Some of the chapter titles are: The Radiology of Asbestosis and Related Neoplasms; Computed Tomography and Malignant Mesothelioma; Radiation Therapy for Pleural Mesothelioma; and Radiation Therapy of Peritoneal Mesothelioma

  13. Managing or Relating?

    DEFF Research Database (Denmark)

    Sproedt, Henrik; Buur, Jacob

    2010-01-01

    This paper describes a case of user-driven innovation. We draw on social capital theory and the concept of complex responsive processes to examine the role of relations for the exchange and generation of knowledge across different knowledge traditions. We argue that innovation as a social phenome...... phenomenon with a high degree of uncertainty and complexity requires more relating and less managing to use conflict as a resource by turning the friction between different knowledge traditions into creative friction....

  14. Relativity theory - topical

    International Nuclear Information System (INIS)

    Schmutzer, E.

    1979-01-01

    Issued on the occasion of Albert Einstein's 100th birthday the book deals topically with the special and general relativity theory. The latest experiments to confirm the relativity theory are described and the historical development of the theory is presented in detail. Emphasis is given to the disclosure of deep insights into the nature of matter. Of interest to experts in physical and natural sciences and to mathematicians

  15. Mass relation for neutrinos

    Science.gov (United States)

    Babu; Barr

    2000-08-07

    A generalization of the well-known Georgi-Jarlskog relation (m(&mgr;)/m(tau)) = 3(m(s)/m(b)) to neutrinos is found in the context of SO(10). This new relation is (m(nu(&mgr;))/m(nu(tau))) = 16(m(c)/m(t)), which is consistent with present data, assuming the Mikheyev-Smirnov-Wolfenstein solution to the solar neutrino problem.

  16. Mass Relation for Neutrinos

    International Nuclear Information System (INIS)

    Babu, K. S.; Barr, S. M.

    2000-01-01

    A generalization of the well-known Georgi-Jarlskog relation (m μ /m τ ) =3(m s /m b ) to neutrinos is found in the context of SO(10) . This new relation is (m ν μ /m ν τ )=16(m c /m t ) , which is consistent with present data, assuming the Mikheyev-Smirnov-Wolfenstein solution to the solar neutrino problem. (c) 2000 The American Physical Society

  17. Classifying Linear Canonical Relations

    OpenAIRE

    Lorand, Jonathan

    2015-01-01

    In this Master's thesis, we consider the problem of classifying, up to conjugation by linear symplectomorphisms, linear canonical relations (lagrangian correspondences) from a finite-dimensional symplectic vector space to itself. We give an elementary introduction to the theory of linear canonical relations and present partial results toward the classification problem. This exposition should be accessible to undergraduate students with a basic familiarity with linear algebra.

  18. The metamorphoses of relativity

    Science.gov (United States)

    Staley, Richard

    This talk will explore the ways that problems shifted and disciplinary boundaries changed around physicists' engagement with relational physics and relativistic thought, first in research dealing with physiology, psychology and geometry in the late nineteenth century and then (a better-known story) moving between physics, mathematics and geometry in the twentieth century. I hope to develop a richer approach for understanding the disciplinary and political significance of relativity, especially by considering in one framework the work of Engels, Mach, Einstein and Planck.

  19. General Relativity and Gravitation

    Science.gov (United States)

    Ehlers, J.; Murdin, P.

    2000-11-01

    The General Theory of Relativity (GR), created by Albert Einstein between 1907 and 1915, is a theory both of gravitation and of spacetime structure. It is based on the assumption that matter, via its energy-momentum, interacts with the metric of spacetime, which is considered (in contrast to Newtonian physics and SPECIAL RELATIVITY) as a dynamical field having degrees of freedom of its own (GRAVI...

  20. INTERPERSONAL RELATIONS IN SCHOOL

    Directory of Open Access Journals (Sweden)

    Siniša Opić

    2016-12-01

    Full Text Available As part of the scientific project titled “The Curriculum of Social Competences and Relations in School”, the aim of this paper is to examine the quality of interpersonal relations between teachers and pupils. On a sample of 432 teachers from 20 towns, 35 primary schools in the Republic of Croatia, and 432 pupils, it was confirmed that there is a difference in the appraisal of the quality of their interpersonal relations. Although the overall quality of interpersonal relations between pupils and teachers is at a moderately satisfactory level, pupils still appraise the quality of interpersonal relations lower than their teachers. In view of latent dimensionality, a factor questionnaire structure was used (14 variables; ordinal type and two main components (subscales determined: didactic support and interaction, and rough verbal and physical treatment. As part of the differential draft of our research, no gender differences were established (between female and male teachers in the appraisal of the quality of interpersonal relations with pupils (on two subscales. The correlation analysis confirmed a low negative statistically significant correlation between the years of service and the subscale rough verbal and physical treatment (Rho=-0.101. In view of the subscale of rough verbal and physical treatment between pupils and teachers, such results on a negative correlation imply that older teachers, as opposed to their younger colleagues, use more corporal punishment in schools, treat pupils rudely, use nasty and impolite words, and call pupils insulting names.

  1. The theories of relativity

    International Nuclear Information System (INIS)

    Deruelle, N.; Uzan, J.P.

    2014-01-01

    This book is a quite complete route towards general relativity via special relativity with a start point at Newton's mechanics. The mathematical formulation is based on tensors. All the relativistic aspects of only classical physics - it means no quantum mechanics - are exposed. This book is divided into 3 books and each book represents a consistent knowledge of physics at a certain time in the past: in Newton's time, in the second half of the 19. century and today. The advantage of this presentation is to make the reader feels the changes over time in the concepts of time, space, gravity, cosmology. Each book is divided into 3, 4 and 5 parts which are sub-divided into numerous chapters. Book 1: Space, time and gravity in Newton's theory, with part 1: kinematics, part 2: dynamics and part 3: gravity. Book 2: Special relativity and Maxwell's theory, with part 1: kinematics, part 2: dynamics, part 3: electromagnetism and part 4: electrodynamics. And Book 3: General relativity and gravity, with part 1: curved space-time and gravity, part 2: Schwarzschild solution and black holes, part 3: general relativity and experiments, part 4: Friedman-Lemaitre solutions and cosmology, and part 5: elements or Riemann geometry. The 3. book dedicated to general relativity, tackles topics like the relationships between space-time curvature and gravity, Schwarzschild solutions and black holes, gravitational waves, Friedmann-Lemaitre solutions and cosmology, and Riemann geometry. (A.C.)

  2. STRATEGI KOMUNIKASI PUBLIC RELATIONS

    Directory of Open Access Journals (Sweden)

    Artis Artis

    2011-11-01

    Full Text Available Living man in interrelates society. Relationship among human being done by gets communication so man one by another one mutually understand and influence regard for the benefit, it that always been practiced by Public Relations( liaison in a governance and also firm institute to reach to the effect which ices. The institute of Public Relations declares for,”Public Relations is overall effort which be passed off by design and berkesenambungan in order to creates and pet keenness and mutual understanding among an organization with whole its member “. In this case, Public Relations in give distribution on manajement's strategy there is two: First, Doing task as part of Public Relations's strategy and involvement in comprehensive process and gives benefit for management an organization. Both of, Public Relations gets role in management strategy in bring off activity to reach to the effect good one gets internal character and also external one correspond to that desirable by good institute on level governance and firm.

  3. De Sitter projective relativity

    CERN Document Server

    Licata, Ignazio; Benedetto, Elmo

    2017-01-01

    This book presents the Projective approach to de Sitter Relativity. It traces the development of renewed interest in models of the universe at constant positive curvature such as "vacuum" geometry. The De Sitter Theory of Relativity, formulated in 1917 with Willem De Sitter's solution of the Einstein equations, was used in different fields during the 1950s and 1960s, in the work of H. Bacry, J.M. LevyLeblond and F.Gursey, to name some important contributors. From the 1960s to 1980s, L. Fantappié and G. Arcidiacono provided an elegant group approach to the De Sitter universe putting the basis for special and general projective relativity. Today such suggestions flow into a unitary scenario, and this way the De Sitter Relativity is no more a "missing opportunity" (F. Dyson, 1972), but has a central role in theoretical physics. In this volume a systematic presentation is given of the De Sitter Projective relativity, with the recent developments in projective general relativity and quantum cosmology.

  4. Algorithmic Relative Complexity

    Directory of Open Access Journals (Sweden)

    Daniele Cerra

    2011-04-01

    Full Text Available Information content and compression are tightly related concepts that can be addressed through both classical and algorithmic information theories, on the basis of Shannon entropy and Kolmogorov complexity, respectively. The definition of several entities in Kolmogorov’s framework relies upon ideas from classical information theory, and these two approaches share many common traits. In this work, we expand the relations between these two frameworks by introducing algorithmic cross-complexity and relative complexity, counterparts of the cross-entropy and relative entropy (or Kullback-Leibler divergence found in Shannon’s framework. We define the cross-complexity of an object x with respect to another object y as the amount of computational resources needed to specify x in terms of y, and the complexity of x related to y as the compression power which is lost when adopting such a description for x, compared to the shortest representation of x. Properties of analogous quantities in classical information theory hold for these new concepts. As these notions are incomputable, a suitable approximation based upon data compression is derived to enable the application to real data, yielding a divergence measure applicable to any pair of strings. Example applications are outlined, involving authorship attribution and satellite image classification, as well as a comparison to similar established techniques.

  5. Dynamics and Relativity

    CERN Document Server

    Forshaw, Jeffrey

    2009-01-01

    A new title in the Manchester Physics Series, this introductory text emphasises physical principles behind classical mechanics and relativity. It assumes little in the way of prior knowledge, introducing relevant mathematics and carefully developing it within a physics context. Designed to provide a logical development of the subject, the book is divided into four sections, introductory material on dynamics, and special relativity, which is then followed by more advanced coverage of dynamics and special relativity. Each chapter includes problems ranging in difficulty from simple to challenging with?solutions for solving problems. Includes?solutions for solving problemsNumerous worked examples included throughout the bookMathematics is carefully explained and developed within a physics environmentSensitive to topics that can appear daunting or confusing

  6. New general relativity

    International Nuclear Information System (INIS)

    Hayashi, K.; Shirafuji, T.

    1979-01-01

    A gravitational theory is formulated on the Weitzenboeck space-time, characterized by the vanishing curvature tensor (absolute parallelism) and by the torsion tensor formed of four parallel vector fields. This theory is called new general relativity, since Einstein in 1928 first gave its original form. New general relativity has three parameters c 1 , c 2 , and lambda, besides the Einstein constant kappa. In this paper we choose c 1 = 0 = c 2 , leaving open lambda. We prove, among other things, that (i) a static, spherically symmetric gravitational field is given by the Schwarzschild metric, that (ii) in the weak-field approximation an antisymmetric field of zero mass and zero spin exists, besides gravitons, and that (iii) new general relativity agrees with all the experiments so far carried out

  7. Global general relativity

    International Nuclear Information System (INIS)

    Penrose, R.

    1979-01-01

    Much theoretical work in General Relativity has been concerned with finding explicit solutions of Einstein field equations. Exact solutions must involve simplifying procedures which in the case of strong gravitational fields may not be valid. Computers can help but complementary to these are the global qualitative mathematics that have been introduced into relativity over the past years. These have shown that Einstein's equations together with suitable inequalities on the energy-momentum tensor can lead inevitably to space-time singularities arising, provided that some qualitative geometric criterion is satisfied. It seems that in suitable situations of gravitational collapse this criterion will be satisfied. Similarly in a cosmological setting the criterion can be applied in the reverse direction in time. There is, however, the unsolved problem in general relativity of cosmic censorship and this is discussed as a consequence of Einstein's equations. (UK)

  8. Elementary general relativity

    International Nuclear Information System (INIS)

    Clarke, C.

    1979-01-01

    The plan of the book is as follows: Chapter 1 develops special relativity in a setting and notation that can immediately be transferred to general relativity. Most of the fundamental geometrical ideas are established here. Chapter 2 gives a more conventional account of some selected applications of special relativity. Chapter 3 is the heart of the book. A geometrical model of space-time is progressively built up, motivated by physical arguments stemming from the equivalence principle, leading to Einstein's field equations. Chapter 4 deals very quickly with the simplest form of weak-field theory with application to gravitational radiation. Chapter 5 concludes the book with a fairly detailed analysis of the Schwarzschild solution, plane fronted gravitational waves, and the Robertson-Walker cosmological solutions. Exercises at the end of each chapter extend the general theory into particular applications, giving a broader picture of the scope of the subject. (author)

  9. Tensors, relativity, and cosmology

    CERN Document Server

    Dalarsson, Mirjana

    2015-01-01

    Tensors, Relativity, and Cosmology, Second Edition, combines relativity, astrophysics, and cosmology in a single volume, providing a simplified introduction to each subject that is followed by detailed mathematical derivations. The book includes a section on general relativity that gives the case for a curved space-time, presents the mathematical background (tensor calculus, Riemannian geometry), discusses the Einstein equation and its solutions (including black holes and Penrose processes), and considers the energy-momentum tensor for various solutions. In addition, a section on relativistic astrophysics discusses stellar contraction and collapse, neutron stars and their equations of state, black holes, and accretion onto collapsed objects, with a final section on cosmology discussing cosmological models, observational tests, and scenarios for the early universe. This fully revised and updated second edition includes new material on relativistic effects, such as the behavior of clocks and measuring rods in m...

  10. Introduction to special relativity

    International Nuclear Information System (INIS)

    Rindler, W.

    1982-01-01

    This is intended as a text for an introductory course on special relativity; it assumes no prior knowledge of relativity. It is intended for the upper undergraduate level and upwards. The first three chapters take a three-dimensional viewpoint for a simple introduction to topics such as the relativity of simultaneity, length contraction, time dilation, the twin paradox and the appearance of moving objects. For the remaining chapters the strongest possible use is made of four-dimensional techniques. Chapter four deals with space-time, chapters five and six with mechanics and electromagnetism. In these a purely synthetic four-tensor approach is adopted. Pure tensor theory is covered in an appendix. The last chapter is on the mechanics of continua. (U.K.)

  11. Essential dynamics and relativity

    CERN Document Server

    O'Donnell, Peter J

    2014-01-01

    Essential Dynamics & Relativity provides students with an introduction to the core aspects of dynamics and special relativity. The author reiterates important ideas and terms throughout and covers concepts that are often missing from other textbooks at this level. He also places each topic within the wider constructs of the theory, without jumping from topic to topic to illustrate a point.The first section of the book focuses on dynamics, discussing the basic aspects of single particle motion and analyzing the motion of multi-particle systems. The book also explains the dynamical behavior of b

  12. Relativity and its roots

    CERN Document Server

    Hoffmann, Banesh

    1998-01-01

    In this fascinating, accessible introduction to one of the most revolutionary developments in modern physics, Einstein scholar Banesh Hoffmann recounts the successive insights that led to both the special and general theories of relativity.Using simple examples from everyday life, the author presents entertaining, nontechnical demonstrations of what relativity actually means and how it has revolutionized our ideas of time and space. Starting with the geometrical and cosmological ideas of the ancient Greeks, the author traces the succession of ideas and advances that paved the way for modern p

  13. Structural Logical Relations

    DEFF Research Database (Denmark)

    Schürmann, Carsten; Sarnat, Jeffrey

    2008-01-01

    Tait's method (a.k.a. proof by logical relations) is a powerful proof technique frequently used for showing foundational properties of languages based on typed lambda-calculi. Historically, these proofs have been extremely difficult to formalize in proof assistants with weak meta-logics......, such as Twelf, and yet they are often straightforward in proof assistants with stronger meta-logics. In this paper, we propose structural logical relations as a technique for conducting these proofs in systems with limited meta-logical strength by explicitly representing and reasoning about an auxiliary logic...

  14. Turbine related fish mortality

    International Nuclear Information System (INIS)

    Eicher, G.J.

    1993-01-01

    A literature review was conducted to assess the factors affecting turbine-related fish mortality. The mechanics of fish passage through a turbine is outlined, and various turbine related stresses are described, including pressure and shear effects, hydraulic head, turbine efficiency, and tailwater level. The methodologies used in determining the effects of fish passage are evaluated. The necessity of adequate controls in each test is noted. It is concluded that mortality is the result of several factors such as hardiness of study fish, fish size, concentrations of dissolved gases, and amounts of cavitation. Comparisons between Francis and Kaplan turbines indicate little difference in percent mortality. 27 refs., 5 figs

  15. Rotating Stars in Relativity

    Directory of Open Access Journals (Sweden)

    Stergioulas Nikolaos

    2003-01-01

    Full Text Available Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on the equilibrium properties and on the nonaxisymmetric instabilities in f-modes and r-modes have been updated and several new sections have been added on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity.

  16. Bourdieu in International Relations

    DEFF Research Database (Denmark)

    The last few years have seen a genuine wave of publications promoting sociology in international relations. Scholars have suggested that Bourdieu’s vocabulary can be applied to study security, diplomacy, migration and global environmental politics. Yet we still lack a systematic and accessible....... The chapters demonstrate how these concepts can be reinterpreted and used in new ways when exposed to Bourdieusian logic. Challenging key pillars of IR scholarship, Bourdieu in International Relations will be of interest to critical theorists, and scholars of IR theory....

  17. Nuclear energy related research

    International Nuclear Information System (INIS)

    Toerroenen, K.; Kilpi, K.

    1985-01-01

    This research programme plan for 1985 covers the nuclear energy related research planned to be carried out at the Technical Research Centre of Finland (VTT) and funded by the Ministry of Trade and Industry in Finland, the Nordic Council of Ministers and VTT

  18. Goedel, relativity, and mind

    International Nuclear Information System (INIS)

    Penrose, Roger

    2007-01-01

    Goedel's acquaintance with Einstein led him to discover, by use of novel techniques, an exotic cosmological model which flouted many preconceived notions, such as the role of Mach's principle in general relativity and the nature of time. Goedel also invoked it in speculations concerning the question of minds

  19. MARC and Relational Databases.

    Science.gov (United States)

    Llorens, Jose; Trenor, Asuncion

    1993-01-01

    Discusses the use of MARC format in relational databases and addresses problems of incompatibilities. A solution is presented that is in accordance with Open Systems Interconnection (OSI) standards and is based on experiences at the library of the Universidad Politecnica de Valencia (Spain). (four references) (EA)

  20. Quantum relativity theory

    International Nuclear Information System (INIS)

    Banai, M.

    1983-11-01

    A quantum relativity theory formulated in terms of Davis' quantum relativity principle is outlined. The first task in this theory as in classical relativity theory is to model space-time, the arena of natural processes. It is argued that the quantum space-time models of Banai introduced in an earlier paper is formulated in terms of Davis' quantum relativity. Then it is shown that the recently proposed classical relativistic quantum theory of Prugovecki and his corresponding classical relativistic quantum model of space-time open the way to introduce in a consistent way the quantum space-time model (the 'canonically quantized Minkowski space') proposed by Banai earlier. The main new aspect of the quantum mechanics of the quantum relativistic particles is, in this model of space-time, that it provides a true mass eigenvalue problem and, that the excited mass states of such particles can be interpreted as classifically relativistic (massive) quantum particles ('elementary particles'). The question of field theory over quantum relativistic models of space-time is also discussed. Finally, it is suggested that 'quarks' should be considered as quantum relativistic particles. (author)

  1. Related Addictive Disorders.

    Science.gov (United States)

    Buck, Tina; Sales, Amos

    This paper provides an overview of addiction related to substance abuse. It provides basic information, prevalence, diagnostic criteria, assessment tools, and treatment issues for eating disorders, compulsive gambling, sex addictions, and work addictions. Eating disorders such as anorexia nervosa and bulimia nervosa, especially affect adolescents.…

  2. Bimetric general relativity

    International Nuclear Information System (INIS)

    Rosen, N.

    1979-01-01

    A modification of general relativity is proposed involving a second metric tensor describing a space-time of constant curvature and associated with the fundamental rest-frame of the universe. The theory generally agrees with the Einstein theory, but gives cosmological models without singularities which can account for present observation, including helium abundance

  3. Related Drupal Nodes Block

    NARCIS (Netherlands)

    Van der Vegt, Wim

    2010-01-01

    Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix.

  4. Nuclear energy related research

    International Nuclear Information System (INIS)

    Salminen, Pertti

    1989-03-01

    This annual Research Programme Plan covers the publicly funded nuclear energy related research planned to be carried out at the Technical Research Centre of Finland (VTT) in 1989. The research will be financed by the Ministry of Trade and Industry, the Finnish Centre for Radiation and Nuclear Safety, the Nordic Council of Ministers and VTT itself

  5. Relational Aggression among Students

    Science.gov (United States)

    Young, Ellie L.; Nelson, David A.; Hottle, America B.; Warburton, Brittney; Young, Bryan K.

    2011-01-01

    "Relational aggression" refers to harm within relationships caused by covert bullying or manipulative behavior. Examples include isolating a youth from his or her group of friends (social exclusion), threatening to stop talking to a friend (the silent treatment), or spreading gossip and rumors by email. This type of bullying tends to be…

  6. Aquinas on Real Relation

    Czech Academy of Sciences Publication Activity Database

    Svoboda, David

    2016-01-01

    Roč. 6, č. 1 (2016), s. 147-172 ISSN 1804-5588 Institutional support: RVO:67985955 Keywords : relation and its foundation * Aquinas * order Subject RIV: AA - Philosophy ; Religion http://www.cupress.cuni.cz/ink2_stat/index.jsp?include=AUC_clanek&id=2868&id=5343&casopis=921&zalozka=0&predkl=0

  7. Nuclear energy related research

    International Nuclear Information System (INIS)

    Salminen, P.; Mattila, L.

    1990-08-01

    The annual Research Programme Plan describes the publicly funded nuclear energy related research to be carried out at the Technical Research Centre of Finland (VTT) in 1990. The research is financed primarily by the Ministry of Trade and Industry (KTM), the Finnish Centre for Radiation and Nuclear Safety (STUK) and VTT itself. Utilities and industry also contribute to some projects

  8. Conformal special relativity

    International Nuclear Information System (INIS)

    Maia, M.D.

    2006-01-01

    It is shown that the information loss/recovery theorem based on the ADS/CFT correspondence is not consistent with the stability of the Schwarzschild or Reissner-Nordstrom black holes. Nonetheless, the conformal invariance of Yang-Mills theory points to new relativity principle compatible with quantum unitarity near those black holes

  9. Is Happinness relative?

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1991-01-01

    textabstractABSTRACT The theory that happiness is relative is based on three postulates: (1) happiness results from comparison. (2) standards of comparison adjust, (3) standards of comparison are arbitrary constructs. On the basis of these postulates the theory predicts: (a) happiness does not

  10. Nuclear energy related research

    International Nuclear Information System (INIS)

    Mattila, L.; Vanttola, T.

    1991-10-01

    The annual Research Programme Plan describes the publicly funded nuclear energy related research to be carried out mainly at the Technical Research Centre of Finland (VTT) in 1991. The research is financed primarily by the Ministry of Trade and Industry (KTM), the Finnish Centre for Radiation and Nuclear Safety (STUK) and VTT itself. Other research institutes, utilities and industry also contribute to many projects

  11. The relations of particles

    International Nuclear Information System (INIS)

    Okun, L.B.

    1991-01-01

    This book presents papers on elementary particle physics, relations between various particles, and the connections between particle physics with other branches of physics. The papers include: Contemporary status and prospects of high-energy physics; Particle physics prospects; and High energy physics

  12. Can Relations be Designed?

    DEFF Research Database (Denmark)

    Skou, Niels Peter; Mikkelsen, Mette

    2014-01-01

    This paper examines the role of design methods in a social innovation project on a Danish Institution for severely physically and mentally handicapped people. The project was focused on ‘designing’ new or better relations between the residents at the institution and the civil society. During the ...

  13. Employment Relations in Denmark

    DEFF Research Database (Denmark)

    Madsen, Jørgen Steen; Due, Jesper Jørgen; Andersen, Søren Kaj

    2011-01-01

    Jørgen Steen Madsen, Jesper Due og Søren Kaj Andersen har skrevet et kapitel om udviklingen i dansk arbejdsmarkedsregulering til bogen International and Comparative Employment Relations, redigeret af Greg Bamber, Russell Lansbury og Nick Wailes. Bogen indeholder bidrag, der præsenterer og...

  14. BNFL and community relations

    International Nuclear Information System (INIS)

    Bolter, H.

    1982-01-01

    The contributions made by BNFL to community relations are described in an illustrated booklet under the headings: introduction (general policy); donations and sponsorships; BNFL talks service; brochures and public information; visits; local liaison committees; industrial training; sponsored students; apprentices. (U.K.)

  15. Nuclear energy related research

    International Nuclear Information System (INIS)

    Rintamaa, R.

    1992-05-01

    The annual Research Programme Plan describes publicly funded nuclear energy related research to be carried out mainly at the Technical Research Centre of Finland (VTT) in 1992. The research is financed primarily by the Ministry of Trade and Industry (KTM), the Finnish Centre for Radiation and Nuclear Safety (STUK) and VTT itself. Other research institutes, utilities and industry also contribute to many projects

  16. Relational Demonic Fuzzy Refinement

    Directory of Open Access Journals (Sweden)

    Fairouz Tchier

    2014-01-01

    Full Text Available We use relational algebra to define a refinement fuzzy order called demonic fuzzy refinement and also the associated fuzzy operators which are fuzzy demonic join (⊔fuz, fuzzy demonic meet (⊓fuz, and fuzzy demonic composition (□fuz. Our definitions and properties are illustrated by some examples using mathematica software (fuzzy logic.

  17. relation in spherical systems

    Indian Academy of Sciences (India)

    D. Bhattacharyya

    2018-02-09

    Feb 9, 2018 ... SMBH than that of the nearby stars. The relation of the. SMBHs to their host galaxies can be seen by the strong correlation between the mass of SMBH and velocity dispersion σ of the stars in the galaxy. This is some- what surprising because the stars are too far from the. SMBH for the velocity dispersion to ...

  18. Decreasing relative risk premium

    DEFF Research Database (Denmark)

    Hansen, Frank

    2007-01-01

    such that the corresponding relative risk premium is a decreasing function of present wealth, and we determine the set of associated utility functions. We find a new characterization of risk vulnerability and determine a large set of utility functions, closed under summation and composition, which are both risk vulnerable...

  19. Sport-Related Concussions

    Science.gov (United States)

    Brady, Don; Brady, Flo

    2011-01-01

    Sport-related concussions (SRC) are not limited to specific age ranges, professional athletes, or gender. The primary focus of much of SRC research pertains to the assessment, management, and return to play (RTP) of the concussed athlete. This article highlights some major issues of SRC along with some controversies that presently exist within the…

  20. Functions of public relations

    OpenAIRE

    Baranov G. V.

    2016-01-01

    the article reveals the importance of communication with the public in the implementation of human rights and the ideals of mankind; characterized by the specificity of public relations in the information culture of belief; PR functions are explained on the criterion of optimization of activity of social interactions on the basis of cultural ideals.

  1. Nuclear energy related research

    International Nuclear Information System (INIS)

    Salminen, Pertti

    1987-02-01

    This annual Research Programme Plan covers the nuclear related research planned to be carried out at the Technical Research Centre of Finland (VTT) in 1987 and funded by the Ministry of Trade and Industry in Finland, the Nordic Council of Ministers and VTT itself

  2. Work-related stress

    NARCIS (Netherlands)

    Houtman, I.L.D.

    2005-01-01

    Changes in the content and organisation of work in recent decades have resulted in an intensification of work, which is commonly regarded as a cause of stress. This report presents trends in the risks and consequences of work-related stress, and identifies how these can be prevented. The focus

  3. Nuclear energy related research

    International Nuclear Information System (INIS)

    Salminen, P.

    1988-02-01

    This annual Research Programme Plan covers the publicly funded nuclear energy related research planned to be carried out at the Technical Research Centre of Finland (VTT) in 1988. The research will be financed by the Ministry of Trade and Industry, the Finnish Centre for Radiation and Nuclear Safety, the Nordic Council of Ministers and VTT itself

  4. Om evalueringsforskningens relative autonomi

    DEFF Research Database (Denmark)

    Nørholm, Morten

    2008-01-01

    Det empiriske udgangspunkt for artiklen "Om evalueringsforskningens relative autonomi - dansk normal evalueringsforskning som et ikke-autonomt (sub)felt i magtens felt" er en række tekster af fire dominerende danske evalueringsforskere. Det teoretiske udgangspunkt er især Pierre Bourdieus teori om...

  5. Correspondences. Equivalence relations

    International Nuclear Information System (INIS)

    Bouligand, G.M.

    1978-03-01

    We comment on sections paragraph 3 'Correspondences' and paragraph 6 'Equivalence Relations' in chapter II of 'Elements de mathematique' by N. Bourbaki in order to simplify their comprehension. Paragraph 3 exposes the ideas of a graph, correspondence and map or of function, and their composition laws. We draw attention to the following points: 1) Adopting the convention of writting from left to right, the composition law for two correspondences (A,F,B), (U,G,V) of graphs F, G is written in full generality (A,F,B)o(U,G,V) = (A,FoG,V). It is not therefore assumed that the co-domain B of the first correspondence is identical to the domain U of the second (EII.13 D.7), (1970). 2) The axiom of choice consists of creating the Hilbert terms from the only relations admitting a graph. 3) The statement of the existence theorem of a function h such that f = goh, where f and g are two given maps having the same domain (of definition), is completed if h is more precisely an injection. Paragraph 6 considers the generalisation of equality: First, by 'the equivalence relation associated with a map f of a set E identical to (x is a member of the set E and y is a member of the set E and x:f = y:f). Consequently, every relation R(x,y) which is equivalent to this is an equivalence relation in E (symmetrical, transitive, reflexive); then R admits a graph included in E x E, etc. Secondly, by means of the Hilbert term of a relation R submitted to the equivalence. In this last case, if R(x,y) is separately collectivizing in x and y, theta(x) is not the class of objects equivalent to x for R (EII.47.9), (1970). The interest of bringing together these two subjects, apart from this logical order, resides also in the fact that the theorem mentioned in 3) can be expressed by means of the equivalence relations associated with the functions f and g. The solutions of the examples proposed reveal their simplicity [fr

  6. Relational time in physics

    International Nuclear Information System (INIS)

    Assis, A.K.T.

    2011-01-01

    Full text: Isaac Newton (1642-1727) defended in his book Mathematical Principles of Natural Philosophy, also know as Principia, published in 1687, the utilization of absolute time in physics. According to him 'absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external'. Leibniz (1646-1716), on the other hand, was against this concept and proposed relative time to replace it: 'As for my opinion, I have said more than once, that I hold space to be something merely relative, as time is; that I hold it to be an order of coexistence, as time is an order of successions'. Leibniz ideas were accepted and developed by Ernst Mach (1838-1916) in his book The Science of Mechanics, published in 1883. In this work we consider the implementation of relational time, as proposed by Leibniz and Mach, and the consequences this implementation will mean for physics as a whole. We consider some specific examples related to mechanics (Newton's bucket experiment, the flattening of the Earth, Foucault's pendulum experiment) and to electromagnetism (Ampere's force between current carrying wires, an electric charge describing a Larmor radius due to a nearby large magnet, two charges orbiting around one another). We generalize these ideas considering the principle of physical proportions (PPP), according to which no absolute magnitudes should appear in the laws of physics. We present some laws satisfying this principle and others which do not comply with it. The laws which do not satisfy the PPP should be based upon incomplete theories. We present the consequences of complete theories complying with this fundamental principle of nature. (author)

  7. Relational time in physics

    Energy Technology Data Exchange (ETDEWEB)

    Assis, A.K.T. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

    2011-07-01

    Full text: Isaac Newton (1642-1727) defended in his book Mathematical Principles of Natural Philosophy, also know as Principia, published in 1687, the utilization of absolute time in physics. According to him 'absolute, true, and mathematical time, of itself, and from its own nature, flows equably without relation to anything external'. Leibniz (1646-1716), on the other hand, was against this concept and proposed relative time to replace it: 'As for my opinion, I have said more than once, that I hold space to be something merely relative, as time is; that I hold it to be an order of coexistence, as time is an order of successions'. Leibniz ideas were accepted and developed by Ernst Mach (1838-1916) in his book The Science of Mechanics, published in 1883. In this work we consider the implementation of relational time, as proposed by Leibniz and Mach, and the consequences this implementation will mean for physics as a whole. We consider some specific examples related to mechanics (Newton's bucket experiment, the flattening of the Earth, Foucault's pendulum experiment) and to electromagnetism (Ampere's force between current carrying wires, an electric charge describing a Larmor radius due to a nearby large magnet, two charges orbiting around one another). We generalize these ideas considering the principle of physical proportions (PPP), according to which no absolute magnitudes should appear in the laws of physics. We present some laws satisfying this principle and others which do not comply with it. The laws which do not satisfy the PPP should be based upon incomplete theories. We present the consequences of complete theories complying with this fundamental principle of nature. (author)

  8. Fluctuation Relations for Currents

    Science.gov (United States)

    Sinitsyn, Nikolai; Akimov, Alexei; Chernyak, Vladimir; Chertkov, Michael

    2011-03-01

    We consider a non-equilibrium statistical system on a graph or a network. Identical particles are injected, interact with each other, traverse, and leave the graph in a stochastic manner described in terms of Poisson rates, possibly strongly dependent on time and instantaneous occupation numbers at the nodes of the graph. We show that the system demonstrates a profound statistical symmetry, leading to new Fluctuation Relations that originate from the supersymmetry and the principle of the geometric universality of currents rather than from the relations between probabilities of forward and reverse trajectories. NSF/ECCS-0925618, NSF/CHE-0808910 and DOE at LANL under Contract No. DE-AC52-06NA25396.

  9. Surviving relatives after suicide

    DEFF Research Database (Denmark)

    Nørrelykke, Helle; Cohrt, Pernille

    and that suicide has become a subject of research, prevention and treatment. Auxiliary Strategies In the 1990s there have been established the Centre for Suicide Research and the Centre for Prevention of Suicide in Denmark and there has been drafted a national policy document which focuses on the need......We would like to focus on the surviving relatives after suicides, because it is generally accepted that it is especially difficult to recover after the loss from suicide and because we know as a fact that one suicide affects five persons on average. Every year approximately 700 people commit...... suicide in Denmark. This means that at least 400 people undergo the trauma it is when one of their near relatives commits suicide. We also know that the loss from suicide involves a lot of conflicting feelings - like anger, shame, guilt and loss and that the lack of therapy/treatment of these difficult...

  10. Relativity without spacetime

    CERN Document Server

    Cosgrove, Joseph K

    2018-01-01

    In 1908, three years after Einstein first published his special theory of relativity, the mathematician Hermann Minkowski introduced his four-dimensional “spacetime” interpretation of the theory. Einstein initially dismissed Minkowski’s theory, remarking that “since the mathematicians have invaded the theory of relativity I do not understand it myself anymore.” Yet Minkowski’s theory soon found wide acceptance among physicists, including eventually Einstein himself, whose conversion to Minkowski’s way of thinking was engendered by the realization that he could profitably employ it for the formulation of his new theory of gravity. The validity of Minkowski’s mathematical “merging” of space and time has rarely been questioned by either physicists or philosophers since Einstein incorporated it into his theory of gravity. Physicists often employ Minkowski spacetime with little regard to the whether it provides a true account of the physical world as opposed to a useful mathematical tool in th...

  11. THE RELATION APICULTURE - TOURISM

    Directory of Open Access Journals (Sweden)

    Goryana Yonkova

    2016-06-01

    Full Text Available The paper presents analyses of the current condition, trends and opportunities for the apiculture development and its relation to tourism in Bulgaria. Beekeeping is considered as a branch of agriculture since its formation after the liberation to the present day and in its dynamics of development for the last 5 years. Resource base including traditions, state, production and marketing of honey is presented. Data from the National Statistics Institute, Ministry of Agriculture, Food beekeepers' associations, processors and traders of honey and bee products, the Ministry of Tourism and tourism industry organizations is analyzed and discussed. Beekeeping is represented in the relation as a resource for development of apitourism, as untraditional attractive specialized type of tourism, which can support farmers through non-agricultural practices. The paper aimed at assisting companies and individuals in the field of agribusiness and apitourism for the realization of bee products and services.

  12. Galilei-isotopic relativities

    International Nuclear Information System (INIS)

    Santilli, R.M.

    1991-09-01

    In this note we further develop the proposal made in preceding works of constructing the infinite family of Lie-isotopic liftings of Galilei's relativity for closed-isolated systems of particles possessing local, potential and selfadjoint, as well as nonlocal, nonhamiltonian and non selfadjoint internal forces. In particular, we show that the nonlinear and nonlocal generalization of the Galilei transformations introduced in a preceding note do indeed represent motion of extended particles within resistive media, but in such a way to coincide with the conventional transformations at the abstract, realization-free level. This allows the preservation of the basic, physical and mathematical axioms of Galilei's relativity under our liftings, and their realization in the most general possible nonlinear, nonlocal and nonhamiltonian way. (author). 18 refs, 1 fig

  13. Very special relativity.

    Science.gov (United States)

    Cohen, Andrew G; Glashow, Sheldon L

    2006-07-14

    By very special relativity (VSR) we mean descriptions of nature whose space-time symmetries are certain proper subgroups of the Poincaré group. These subgroups contain space-time translations together with at least a two-parameter subgroup of the Lorentz group isomorphic to that generated by K(x) + J(y) and K(y)- J(x). We find that VSR implies special relativity (SR) in the context of local quantum field theory or of conservation. Absent both of these added hypotheses, VSR provides a simulacrum of SR for which most of the consequences of Lorentz invariance remain wholly or essentially intact, and for which many sensitive searches for departures from Lorentz invariance must fail. Several feasible experiments are discussed for which Lorentz-violating effects in VSR may be detectable.

  14. Numerical relativity beyond astrophysics

    Science.gov (United States)

    Garfinkle, David

    2017-01-01

    Though the main applications of computer simulations in relativity are to astrophysical systems such as black holes and neutron stars, nonetheless there are important applications of numerical methods to the investigation of general relativity as a fundamental theory of the nature of space and time. This paper gives an overview of some of these applications. In particular we cover (i) investigations of the properties of spacetime singularities such as those that occur in the interior of black holes and in big bang cosmology. (ii) investigations of critical behavior at the threshold of black hole formation in gravitational collapse. (iii) investigations inspired by string theory, in particular analogs of black holes in more than 4 spacetime dimensions and gravitational collapse in spacetimes with a negative cosmological constant.

  15. LAMA2-related myopathy

    DEFF Research Database (Denmark)

    Løkken, Nicoline; Born, Alfred Peter; Duno, Morten

    2015-01-01

    INTRODUCTION: Muscular dystrophy caused by LAMA2-gene mutations is an autosomal recessive disease typically presenting as a severe, early-onset congenital muscular dystrophy (CMD). However, milder cases with a limb-girdle type muscular dystrophy (LGMD) have been described. METHODS: In this study......, we assessed the frequency and phenotypic spectrum of LAMA2-related muscular dystrophy in CMD (n = 18) and LGMD2 (n = 128) cohorts identified in the last 15 years in eastern Denmark. The medical history, brain-MRI, muscle pathology, muscle laminin-α2 expression, and genetic analyses were assessed....... RESULTS: Molecular genetics revealed 2 pathogenic LAMA2 mutations in 5 of 18 CMD and 3 of 128 LGMD patients, corresponding to a LAMA2-mutation frequency of 28% in the CMD and 2.3% in the LGMD cohorts, respectively. CONCLUSIONS: This study demonstrates a wide clinical spectrum of LAMA2-related muscular...

  16. Hemodialysis-related headache.

    Science.gov (United States)

    Sav, Murat Yusuf; Sav, Tansu; Senocak, Elif; Sav, Nadide Melike

    2014-10-01

    Headache is one of the most frequently encountered neurological symptoms during hemodialysis. According to International Classification of Headache criteria dialysis-related headache was defined as the headache occurring during hemodialysis with no specific characteristic. It resolves spontaneously within 72 hours after the hemodialysis session ends. There are few studies in the literature investigating the clinical features of dialysis headache. The pathophysiology of hemodialysis-related headache is not known, but various triggering factors have been identified, including changes in blood pressure, serum sodium and magnesium levels during hemodialysis sessions, caffeine deprivation and stress. The aim of this article is to evaluate and analyze features of headache in patients undergoing hemodialysis. © 2014 International Society for Hemodialysis.

  17. Offentlighed og Public Relations

    Directory of Open Access Journals (Sweden)

    Lars Heltoft

    1993-09-01

    Full Text Available Lars Heltoft, der er en af grundlæggerne af Public Relationsuddannelsen på Roskilde Universitetscenter, kaster i artiklen et kritisk blik på den akademiske forskning i feltet public relations. Selv i nyere udgaver af PR-forskningen - af mange anset for "progressive", f.eks. James Grunings og Jon Whites arbejder - ser Lars Heltoft tydelige spor af PR- professionens selvforståelse og legitimationsbehov. Resultatet er, at den "offentlighed", der burde være kernen i den videnskabelige beskæftigelse med public relations, "forsvinder i den blå luft". Han argumenterer for, at Habermas´ forestilling om "offentlighed" stadig institutionaliserer mulig- heden for kritisk diskurs inden for feltet, samtidig med at han i sproghand- lingsteoretisk perspektiv problematiserer Habermas´ legitimationsbegreb, fordi det undtager private virksomheder og organisationer.

  18. Numerical relativity beyond astrophysics.

    Science.gov (United States)

    Garfinkle, David

    2017-01-01

    Though the main applications of computer simulations in relativity are to astrophysical systems such as black holes and neutron stars, nonetheless there are important applications of numerical methods to the investigation of general relativity as a fundamental theory of the nature of space and time. This paper gives an overview of some of these applications. In particular we cover (i) investigations of the properties of spacetime singularities such as those that occur in the interior of black holes and in big bang cosmology. (ii) investigations of critical behavior at the threshold of black hole formation in gravitational collapse. (iii) investigations inspired by string theory, in particular analogs of black holes in more than 4 spacetime dimensions and gravitational collapse in spacetimes with a negative cosmological constant.

  19. Rotating stars in relativity.

    Science.gov (United States)

    Paschalidis, Vasileios; Stergioulas, Nikolaos

    2017-01-01

    Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on equilibrium properties and on nonaxisymmetric oscillations and instabilities in f -modes and r -modes have been updated. Several new sections have been added on equilibria in modified theories of gravity, approximate universal relationships, the one-arm spiral instability, on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity including both hydrodynamic and magnetohydrodynamic studies of these objects.

  20. Einstein and relativity

    International Nuclear Information System (INIS)

    Cullwick, E.G.

    1979-01-01

    Einstein published his Special Theory of Relativity in 1905 and in 1915 his General Theory which predicted the bending of light rays passing near the sun. This prediction was apparently confirmed experimentally in 1919 bringing Einstein popular acclaim. Einstein's work is reviewed and the question of whether he was in fact first in the field is examined with especial reference to the work of Maxwell, Lorentz and Poincare. (U.K.)

  1. On Allometry Relations

    Science.gov (United States)

    2012-07-06

    German polymath Gauss64 and the Amer- ican mathematician Adrian1 introduced into science the law of frequency of errors, the French physicist ...00-2012 4. TITLE AND SUBTITLE On Allometry Relations 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT ...AR was given by Sarrus and Rameaux.188 Schmidt–Nielsen195 records that this team of a mathematician and a physician reasoned that the heat gener- ated

  2. Corrupt Relational Contracting

    OpenAIRE

    Johann Graf Lambsdorff; Sitki Utku Teksoz

    2002-01-01

    Because corruption must be hidden from the public and is not enforced by courts it entails transaction costs, which are larger than those from legal exchange. This suggests that corrupt contracts are primarily relational contracts where legal exchange serves as a basis for sealing and enforcing corrupt agreements. Legal exchange not only provides for corrupt opportunities, but for the necessary enforcement mechanisms. Examples of such legal exchange are long-term business exchange, belonging ...

  3. Relativity of Visual Communication

    OpenAIRE

    Arto Mutanen

    2016-01-01

    Communication is sharing and conveying information. In visual communication especially visual messages have to be formulated and interpreted. The interpretation is relative to a method of information presentation method which is human construction. This holds also in the case of visual languages. The notions of syntax and semantics for visual languages are not so well founded as they are for natural languages. Visual languages are both syntactically and semantically dense. The density is conn...

  4. Relativity and accelerator engineering

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2017-09-01

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  5. Complex manifolds in relativity

    International Nuclear Information System (INIS)

    Flaherty, E.J. Jr.

    1975-01-01

    Complex manifold theory is applied to the study of certain problems in general relativity. The first half of the work is devoted to the mathematical theory of complex manifold. Then a brief review of general relativity is given. It is shown that any spacetime admits locally an almost Hermitian structure, suitably modified to be compatible with the indefinite metric of spacetime. This structure is integrable if and only if the spacetime admits two geodesic and shearfree null congruences, thus in particular if the spacetime is type D vacuum or electrified. The structure is ''half-integrable'' in a suitable sense if and only if the spacetime admits one geodesic and shearfree null congruence, thus in particular for all algebraically special vacuum spacetimes. Conditions for the modified Hermitian spacetime to be Kahlerian are presented. The most general metric for such a modified Kahlerian spacetime is found. It is shown that the type D vacuum and electrified spacetimes are conformally related to modified Kahlerian spacetimes by a generally complex conformal factor. These latter are shown to possess a very rich structure, including the existence of Killing tensors and Killing vectors. A new ''explanation'' of Newman's complex coordinate transformations is given. It is felt to be superior to previous ''explanations'' on several counts. For example, a physical interpretation in terms of a symmetry group is given. The existence of new complex coordinate transformations is established: Nt is shown that any type D vacuum spacetime is obtainable from either Schwarzschild spacetime or ''C'' spacetime by a complex coordinate transformation. Finally, some related topics are discussed and areas for future work are outlined. (Diss. Abstr. Int., B)

  6. Relational Demonic Fuzzy Refinement

    OpenAIRE

    Tchier, Fairouz

    2014-01-01

    We use relational algebra to define a refinement fuzzy order called demonic fuzzy refinement and also the associated fuzzy operators which are fuzzy demonic join $({\\bigsqcup }_{\\mathrm{\\text{f}}\\mathrm{\\text{u}}\\mathrm{\\text{z}}})$ , fuzzy demonic meet $({\\sqcap }_{\\mathrm{\\text{f}}\\mathrm{\\text{u}}\\mathrm{\\text{z}}})$ , and fuzzy demonic composition $({\\square }_{\\mathrm{\\text{f}}\\mathrm{\\text{u}}\\mathrm{\\text{z}}})$ . Our definitions and properties are illustrated by some examples using ma...

  7. Three forms of relativity

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1992-01-01

    The physical sense of three forms of the relativity is discussed. The first - instant from - respects in fact the traditional approach based on the concept of instant distance. The normal form corresponds the radar formulation which is based on the light or retarded distances. The front form in the special case is characterized by 'observable' variables, and the known method of k-coefficient is its obvious expression. 16 refs

  8. File: International bilateral relations

    International Nuclear Information System (INIS)

    Feltin, Ch.; Rabouhams, J.; Bravo, X.; Rousseau, M.; Le Breton, S.; Saint Raymond, Ph.; Brigaud, O.; Pertuis, V.; McNair, J.; Sayers, M.R.; Bye, R.; Scherrer, J.

    1998-01-01

    Since its creation in 1973, the Authority of Safety was assigned missions in the international field with following objectives: to develop information exchanges with its foreign counterpart, to make know and to explain the French approach and practice; to give to concerned countries the useful information on french nuclear facilities situated near the border; This file shows with some examples, how bilateral relations allow to fill up these objectives and how the French Authority got the foreign experience. (N.C.)

  9. Relativity and accelerator engineering

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Schenefeld (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2017-09-15

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  10. Matter in general relativity

    Science.gov (United States)

    Ray, J. R.

    1982-01-01

    Two theories of matter in general relativity, the fluid theory and the kinetic theory, were studied. Results include: (1) a discussion of various methods of completing the fluid equations; (2) a method of constructing charged general relativistic solutions in kinetic theory; and (3) a proof and discussion of the incompatibility of perfect fluid solutions in anisotropic cosmologies. Interpretations of NASA gravitational experiments using the above mentioned results were started. Two papers were prepared for publications based on this work.

  11. Forces in general relativity

    International Nuclear Information System (INIS)

    Ridgely, Charles T

    2010-01-01

    Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced by an observer in general coordinates. The general force is then applied to the local co-moving coordinate system of a uniformly accelerating observer, leading to an expression of the inertial force experienced by the observer. Next, applying the general force in Schwarzschild coordinates is shown to lead to familiar expressions of the gravitational force. As a more complex demonstration, the general force is applied to an observer in Boyer-Lindquist coordinates near a rotating, Kerr black hole. It is then shown that when the angular momentum of the black hole goes to zero, the force on the observer reduces to the force on an observer held stationary in Schwarzschild coordinates. As a final consideration, the force on an observer moving in rotating coordinates is derived. Expressing the force in terms of Christoffel symbols in rotating coordinates leads to familiar expressions of the centrifugal and Coriolis forces on the observer. It is envisioned that the techniques presented herein will be most useful to graduate level students, as well as those undergraduate students having experience with general relativity and tensor analysis.

  12. The elements of relativity

    CERN Document Server

    Wittman, David

    2018-01-01

    Relativity has much to offer for a well-rounded education. Yet books on relativity either assume a strong background in physics and math, aimed at advanced physics students, or, alternatively, offer a broad description with little intellectual challenge. This book bridges the gap. It aims at readers with essentially no physics or math background, who still find it rewarding to think rigorously. The book takes a "thinking tools" approach, by first making readers comfortable with a new thinking tool and then applying it to learn more about how nature works. By the end of the book, readers will have collected a versatile toolbox and will be comfortable using the tools to think about and really understand the intriguing phenomena they may have only heard about, including the twin paradox, black holes, and time travel. End-of-chapter exercises span a range of difficulty, allowing adventurous readers to stretch their understanding further as desired. Students who have studied, or are studying, relativity at a more...

  13. General Relativity and Gravitation

    Science.gov (United States)

    Ashtekar, Abhay; Berger, Beverly; Isenberg, James; MacCallum, Malcolm

    2015-07-01

    Part I. Einstein's Triumph: 1. 100 years of general relativity George F. R. Ellis; 2. Was Einstein right? Clifford M. Will; 3. Cosmology David Wands, Misao Sasaki, Eiichiro Komatsu, Roy Maartens and Malcolm A. H. MacCallum; 4. Relativistic astrophysics Peter Schneider, Ramesh Narayan, Jeffrey E. McClintock, Peter Mészáros and Martin J. Rees; Part II. New Window on the Universe: 5. Receiving gravitational waves Beverly K. Berger, Karsten Danzmann, Gabriela Gonzalez, Andrea Lommen, Guido Mueller, Albrecht Rüdiger and William Joseph Weber; 6. Sources of gravitational waves. Theory and observations Alessandra Buonanno and B. S. Sathyaprakash; Part III. Gravity is Geometry, After All: 7. Probing strong field gravity through numerical simulations Frans Pretorius, Matthew W. Choptuik and Luis Lehner; 8. The initial value problem of general relativity and its implications Gregory J. Galloway, Pengzi Miao and Richard Schoen; 9. Global behavior of solutions to Einstein's equations Stefanos Aretakis, James Isenberg, Vincent Moncrief and Igor Rodnianski; Part IV. Beyond Einstein: 10. Quantum fields in curved space-times Stefan Hollands and Robert M. Wald; 11. From general relativity to quantum gravity Abhay Ashtekar, Martin Reuter and Carlo Rovelli; 12. Quantum gravity via unification Henriette Elvang and Gary T. Horowitz.

  14. Lectures on general relativity

    CERN Document Server

    Papapetrou, Achille

    1974-01-01

    This book is an elaboration of lecture notes for the graduate course on General Rela­ tivity given by the author at Boston University in the spring semester of 1972. It is an introduction to the subject only, as the time available for the course was limited. The author of an introduction to General Relativity is faced from the beginning with the difficult task of choosing which material to include. A general criterion as­ sisting in this choice is provided by the didactic character of the book: Those chapters have to be included in priority, which will be most useful to the reader in enabling him to understand the methods used in General Relativity, the results obtained so far and possibly the problems still to be solved. This criterion is not sufficient to ensure a unique choice. General Relativity has developed to such a degree, that it is impossible to include in an introductory textbook of a reasonable length even a very condensed treatment of all important problems which have been discussed unt...

  15. Intraprofessional relations in nursing.

    Science.gov (United States)

    Duddle, Maree; Boughton, Maureen

    2007-07-01

    This paper is a report of a study to explore the way in which Registered Nurses relate to and interact with each other in the workplace, and to identify factors that influence nurses' interactions with each other. Intraprofessional relations are an important topic both for nurses and nursing as we face the ongoing challenges of nurse shortages. Poor colleague relationships, together with workplace conflict, cause job dissatisfaction. As a consequence, some nurses leave the profession while others continue working but remain chronically unhappy. An explanatory multiple case study design was adopted. Data were collected from multiple sources on three different wards within one hospital in Australia between July 2005 and January 2006. The workplace can be a difficult place for both very experienced and less experienced nurses, regardless of the clinical environment. Nurses navigate their way in the workplace through a series of complex negotiations with each other and develop skills to assess the potential success of an interaction before approaching another nurse. Some also develop a resilience to conflict in their workplace, accepting it as part of working life. Creation of a more positive work environment requires increased understanding of the way nurses relate to each other and appreciation of the factors in the environment that contribute to conflict and a negative atmosphere. This appreciation is a necessary prerequisite to developing a more satisfying and productive workplace enhancing the recruitment of new nurses and the retention of experienced nurses.

  16. Statin-related myotoxicity.

    Science.gov (United States)

    Fernandes, Vera; Santos, Maria Joana; Pérez, Antonio

    2016-05-01

    Statin therapy has a very important role in decreasing cardiovascular risk, and treatment non-compliance may therefore be a concern in high cardiovascular risk patients. Myotoxicity is a frequent side effect of statin therapy and one of the main causes of statin discontinuation, which limits effective treatment of patients at risk of or with cardiovascular disease. Because of the high proportion of patients on statin treatment and the frequency of statin-related myotoxicity, this is a subject of concern in clinical practice. However, statin-related myotoxicity is probably underestimated because there is not a gold standard definition, and its diagnosis is challenging. Moreover, information about pathophysiology and optimal therapeutic options is scarce. Therefore, this paper reviews the knowledge about the definition, pathophysiology and predisposing conditions, diagnosis and management of statin-related myotoxicity, and provides a practical scheme for its management in clinical practice. Copyright © 2016 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

  17. Teleseismic magnitude relations

    Directory of Open Access Journals (Sweden)

    Markus Båth

    2010-02-01

    Full Text Available Using available sets of magnitude determinations, primarily from Uppsala seismological bulletin, various extensions are made of the Zurich magnitude recommendations of 1967. Thus, body-wave magnitude (m and surface-wave magnitudes (M are related to each other for 12 different earthquake regions as well as world-wide. Depth corrections for M are derived for all focal depths. Formulas are developed which permit calculation of M also from vertical component long-period seismographs. Body-wave magnitudes from broad-band and narrow-band short-period seismographs are compared and relations deduced. Applications are made both to underground nuclear explosions and to earthquakes. The possibilities of explosion-earthquake discrimination on the basis of magnitudes are examined, as well as the determination of explosive yield from magnitudes. For earthquakes, relations between magnitudes of main earthquakes and largest aftershocks are investigated. A world-wide station network for more homogeneous magnitude determinations is suggested in order to provide the necessary reference system.

  18. Relativities of fundamentality

    Science.gov (United States)

    McKenzie, Kerry

    2017-08-01

    S-dualities have been held to have radical implications for our metaphysics of fundamentality. In particular, it has been claimed that they make the fundamentality status of a physical object theory-relative in an important new way. But what physicists have had to say on the issue has not been clear or consistent, and in particular seems to be ambiguous between whether S-dualities demand an anti-realist interpretation of fundamentality talk or merely a revised realism. This paper is an attempt to bring some clarity to the matter. After showing that even antecedently familiar fundamentality claims are true only relative to a raft of metaphysical, physical, and mathematical assumptions, I argue that the relativity of fundamentality inherent in S-duality nevertheless represents something new, and that part of the reason for this is that it has both realist and anti-realist implications for fundamentality talk. I close by discussing the broader significance that S-dualities have for structuralist metaphysics and for fundamentality metaphysics more generally.

  19. Cancer-related anemia

    International Nuclear Information System (INIS)

    Abdel-Rzaeq, Hikmat N.

    2004-01-01

    Anemia is the most common hematological abnormality in cancer patients is often under-recognized and undertreated. The pathogenesis of cancer anemia is complex and most of time multifactorial; involving factors related to the tumor itself or its therapy. While anemia can be present in a wide range of symptoms, involing almost every organ, it is beleived that it contributes much to cancer-related-fatigue, one of the most common symptoms in cancer patients. In addition there is increasing evidence to suggest that anemia is an independent factor adversely affecting tumor reponse and patient survival. While blood transfusion was the only option to treat cancer related anemia, the use of recombinant human erythropoietin (rHuEPO) is becomig the new standard of care, more so with the recent studies demonstrating the feasibility of a sigle weekly injection .Things are even getting better with the recent approval of a new form of rHuEPO; Darbepoetin an analogue with a 3-fold longer half-life. In addition to its effects in raising homoglobin, several well controlled studies demonstrated decrease in transfusion requirementsand better qualify of life assessed objectively using standard assesments scales. (author)

  20. Viking relativity experiment

    International Nuclear Information System (INIS)

    Shapiro, I.I.; Reasenberg, R.D.; MacNeil, P.E.; Goldstein, R.B.; Brenkle, J.P.; Cain, D.L.; Komarek, T.; Zygielbaum, A.I.; Cuddihy, W.F.; Michael, W.H. Jr.

    1977-01-01

    Measurements of the round-trip time of flight of radio signals transmitted from the earth to the Viking spacecraft are being analyzed to test the predictions of Einstein's theory of general relativity. According to this theory the signals will be delayed by up to approx.250 μs owing to the direct effect of solar gravity on the propagation. A very preliminary qualitative analysis of the Viking data obtained near the 1976 superior conjunction of Mars indicates agreement with the predictions to within the estimated uncertainty of 0.5%

  1. Theory of relations

    CERN Document Server

    Fraïssé, R

    2011-01-01

    The first part of this book concerns the present state of the theory of chains (= total or linear orderings), in connection with some refinements of Ramsey's theorem, due to Galvin and Nash-Williams. This leads to the fundamental Laver's embeddability theorem for scattered chains, using Nash-Williams' better quasi-orderings, barriers and forerunning.The second part (chapters 9 to 12) extends to general relations the main notions and results from order-type theory. An important connection appears with permutation theory (Cameron, Pouzet, Livingstone and Wagner) and with logics (existence criter

  2. A Concurrent Logical Relation

    DEFF Research Database (Denmark)

    Birkedal, Lars; Sieczkowski, Filip; Thamsborg, Jacob Junker

    2012-01-01

    We present a logical relation for showing the correctness of program transformations based on a new type-and-effect system for a concurrent extension of an ML-like language with higher-order functions, higher-order store and dynamic memory allocation. We show how to use our model to verify a number....... To the best of our knowledge, this is the first such result for a concurrent higher-order language with higher-order store and dynamic memory allocation....

  3. The Viking Relativity Experiment

    Science.gov (United States)

    Shapiro, I. I.; Reasenberg, R. D.; Macneil, P. E.; Goldstein, R. B.; Brenkle, J. P.; Cain, D. L.; Komarek, T.; Zygielbaum, A. I.; Cuddihy, W. F.; Michael, W. H., Jr.

    1977-01-01

    Measurements of the round-trip time of flight of radio signals transmitted from the earth to the Viking spacecraft are being analyzed to test the predictions of Einstein's theory of general relativity. According to this theory the signals will be delayed by up to approximately 250 microsec owing to the direct effect of solar gravity on the propagation. A very preliminary qualitative analysis of the Viking data obtained near the 1976 superior conjunction of Mars indicates agreement with the predictions to within the estimated uncertainty of 0.5%.

  4. Twistors in general relativity

    International Nuclear Information System (INIS)

    Penrose, R.

    1987-01-01

    The two most significant definitions of a twistor in (conformally) flat space-time are that given by solutions of the twistor equation and that given by α-planes in the complexification of the space-time. It is shown that these concepts are naturally dual to one another, and that they give rise to various different twistor concepts in curved space-time when referred to submanifolds of differing dimension. One of these concepts, that of 2-surface twistors, gives rise to a quasi-local definition of mass (and angular momentum). The status of this definition is explored in relation to various examples. (author)

  5. Relative Reality: the Movie

    Science.gov (United States)

    Onley, David; Steinberg, Gary

    2004-04-01

    The consequences of the Special Theory of Relativity are explored in a virtual world in which the speed of light is only 10 m/s. Ray tracing software and other visualization tools, modified to allow for the finite speed of light, are employed to create a video that brings to life a journey through this imaginary world. The aberation of light, the Doppler effect, the altered perception of time and power of incoming radiation are explored in separate segments of this 35 min video. Several of the effects observed are new and quite unexpected. A commentary and animated explanations help keep the viewer from losing all perspective.

  6. Challenging Scandinavian employment relations

    DEFF Research Database (Denmark)

    Ibsen, Christian Lyhne; Larsen, Trine Pernille; Madsen, Jørgen Steen

    2011-01-01

    and employment relations in the Danish, Norwegian and Swedish public sector. In this paper, we argue that although differences exist across the Scandinavian countries, it is evident that they have managed to adopt and implement NPM-inspired reforms without dismantling their universal welfare services and strong......Building on the convergence/divergence approach, this paper examines whether recent new public management (NPM) inspired reforms entailing inter alia cutbacks in the public sector, marketisation and management by performance measures have had significant implications for service provision...... traditions of collective bargaining in the public sector. However, this restructuring is taking its toll on the work environment....

  7. CKM related measurements

    International Nuclear Information System (INIS)

    Dalseno, J.

    2014-01-01

    We present recent CKM-related results on the unitary triangle for B d decays from the BaBar and Belle Collaborations which collect BB-bar pairs at the Υ(4S) resonance produced in asymmetric e + e - collisions. These include the decay channels B 0 → (cc-bar)K 0 and B 0 → D (*)+ D (*)- , which are sensitive to the CP violating phase φ 1 : B 0 → α 1 (1260) ± π ± , which can constrain the CP violating phase φ 2 , and B → hlν, from which V ub can be determined. (author)

  8. Studies Relating to EVA

    Science.gov (United States)

    1997-01-01

    In this session, Session JA1, the discussion focuses on the following topics: The Staged Decompression to the Hypobaric Atmosphere as a Prophylactic Measure Against Decompression Sickness During Repetitive EVA; A New Preoxygenation Procedure for Extravehicular Activity (EVA); Metabolic Assessments During Extra-Vehicular Activity; Evaluation of Safety of Hypobaric Decompressions and EVA From Positions of Probabilistic Theory; Fatty Acid Composition of Plasma Lipids and Erythrocyte Membranes During Simulation of Extravehicular Activity; Biomedical Studies Relating to Decompression Stress with Simulated EVA, Overview; The Joint Angle and Muscle Signature (JAMS) System - Current Uses and Future Applications; and Experimental Investigation of Cooperative Human-Robotic Roles in an EVA Work Site.

  9. Nuclear public relations campaign

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    A two-day hearing to investigate DOE's participation in a $30 million nuclear public relations program at a time when the country is asked to decrease spending and in conjunction with similar efforts by the nuclear industry focused on the issue of whether ratepayers or shareholders should finance the effort. Shelby Brewer, Assistant Secretary for Nuclear Energy, defended the expenditures as a response to public demand for information and the need to correct misinformation. The testimony of 14 other witnesses includes the views of citizen and professional groups, utilities, and government agencies. Their testimony is followed by additional material submitted for the record. (DCK)

  10. Public relations strategy

    International Nuclear Information System (INIS)

    Kukovica, T.; Mele, I.

    1996-01-01

    NIMBY (Not In My Back Yard) syndrome has become a major problem in the field of environmental planning. Also in Slovenia. Agency for Radwaste management was established by the Slovene government in 1991. Our main objective is to provide the final disposal of radioactive waste in Slovenia. Overcoming the NIMBY syndrome is therefore the primary aim of Agency's PR (public relations) strategy. Agency's public relations strategy was prepared in 1993. After very unpleasant experience with NIMBY syndrome in local community where one of the potential locations for low and intermediate level repository was identified the strategy was renewed in 1994. It is divided into two parts: information and education. The first one includes providing information to the media, surveys of press clippings, interviews, press conferences, public opinion polls and publishing articles. Agency's first task in the field of education was to prepare different materials like: leaflets, Agency's newspaper and videos. Materials were distributed to various target publics. There is also a special program of lectures for youngsters. All those activities and projects have been successfully realized within the last year. Plans of PR activities for this year are focused on informing the local community about remediation of temporary storage of radioactive waste near village Zavratec. Other new projects are also under preparation like: new leaflets, presentation on Internet, journalist's guide to rad waste management, most frequently asked questions and answers. (author)

  11. Negotiation within labor relations

    Directory of Open Access Journals (Sweden)

    Iulia BĂDOI

    2014-06-01

    Full Text Available Negotiation is the process we use in order to obtain things that we want and are controlled by others. Any desire we intend to fulfill, any need that we are obliged to meet is a potential bargaining situations. Between groups and individuals, negotiation occurs naturally, as some have one thing that the other wants and is willing to bargain to get it. More or less we are all involved in negotiations: closing a contract, buying a thing, obtaining sponsorships, collective decision making, conflict resolution, agreement on work plans. Within the field of labor relations, negotiation can occur on the occasion of closing / amending employment contracts or in order to regulate employment or work relations. Moreover, used properly, the negotiation can be an effective tool for solving labor disputes, with benefits for both involved parties. This paper aims to present negotiating principles and steps to follow in planning and preparing negotiations and the negotiating techniques that can lead to a successful negotiation based on a well-developed plan.

  12. Relativity of Electric Quantity

    Directory of Open Access Journals (Sweden)

    GAO Zhong-wen

    2017-04-01

    Full Text Available The demonstration foundation,which is used to demonstrate that observed values from the interaction force between two charges,which are not at the same point would be different in different reference frames,is that the transmission of the interaction between charges needs time. Firstly,this paper analyzes the foundation of hypothetical process that the electric field and the magnetic field are built by one charge,and then the electromagnetic field would be transferred to another charge in vacuo by the speed of light,and produces force. It points out that from the simultaneity of relativity,the force applied to charge would occur in different time in the different reference frames,the force would be neither in the same size nor in the opposite direction,and Newton’s Third Law is not valid longer, the deeper cause of these conclusions would be known. On this basis,this paper gives the basis that force would keep invariant in different reference frames,and according to this condition,with the situation of the charge that under the Coulombian force and electromagnetism,the relative form of expression and demonstration methods of electric quantity in different reference frames are given. On the basis of the hypothesis that force would keep invariant in different reference frames,with the similar derivation process,the mass relativity equation of Einstein would be obtained.

  13. Sleep-related laryngospasm.

    Science.gov (United States)

    Thurnheer, R; Henz, S; Knoblauch, A

    1997-09-01

    The term "sleep-related laryngospasm" refers to episodic, abrupt interruption of sleep accompanied by feelings of acute suffocation followed by stridor. The condition is included in the diagnostic and coding manual of the American Sleep Disorders Association (ASDA), but there are few references in the peer-reviewed literature. Our description of the distinct clinical picture associated with this condition is based on an analysis of the histories of a series of 10 patients. The patients and their families gave precise, uniform accounts of the dramatic attacks. Diagnostic work-up included pulmonary and gastroenterological assessment. All patients reported sudden awakening from sleep due to feelings of acute suffocation, accompanied by intense fear. Apnoea lasting 5-45 s was followed by stridor. Breathing returned to normal within minutes. Patients were left exhausted by the attacks. Nine of our 10 patients had evidence of gastro-oesophageal reflux and six responded to antireflux therapy. We conclude that the nocturnal choking attacks (and the occasional daytime attacks experienced by some of the patients) are caused by laryngospasm. The pathogenesis of the apparent underlying laryngeal irritability is unknown. The condition may be related to a gastro-oesophageal reflux.

  14. My relational self psychology.

    Science.gov (United States)

    Teicholz, Judith Guss

    2009-04-01

    In this article, I suggest recent sources of influence on psychoanalysis and describe a contemporary relational self psychology that is my personal attempt at integration. Even with this integration, I struggle to find the right "therapeutic" balance between my essential but imperfect instrument for empathic listening, on the one hand, and the risks of authentic engagement, on the other. These dialectical tensions in me mirror those in the psychoanalytic community as a whole, poised between a scientifically based practice and a healing "art"--or between a complex but teachable methodology or discipline-and an ordinary (yet extraordinary) human relationship in which spontaneity and even improvisation play a role. Complicating this balancing act, there is new evidence from neuroscientists, attachment theorists, and infant-caregiver researchers that, from birth onward, bidirectional influences on brain and psychic development create contingent and unpredictable outcomes in every intimately related dyad. Thus, the contemporary analyst must expect to be changed by the work and--while taking full responsibility for his or her own contribution--must recognize patient and analyst as co-creators of the psychoanalytic project. At the same time that we now recognize contingency, complexity, and chaos at the heart of human minds and relationships, we also acknowledge the central importance of a sense of continuity and coherence as the individual undertakes the pursuit of goals and relationships in life. What kind of relationship can facilitate these qualities in the sense of self? That is the question that this article undertakes to answer.

  15. Discriminative Relational Topic Models.

    Science.gov (United States)

    Chen, Ning; Zhu, Jun; Xia, Fei; Zhang, Bo

    2015-05-01

    Relational topic models (RTMs) provide a probabilistic generative process to describe both the link structure and document contents for document networks, and they have shown promise on predicting network structures and discovering latent topic representations. However, existing RTMs have limitations in both the restricted model expressiveness and incapability of dealing with imbalanced network data. To expand the scope and improve the inference accuracy of RTMs, this paper presents three extensions: 1) unlike the common link likelihood with a diagonal weight matrix that allows the-same-topic interactions only, we generalize it to use a full weight matrix that captures all pairwise topic interactions and is applicable to asymmetric networks; 2) instead of doing standard Bayesian inference, we perform regularized Bayesian inference (RegBayes) with a regularization parameter to deal with the imbalanced link structure issue in real networks and improve the discriminative ability of learned latent representations; and 3) instead of doing variational approximation with strict mean-field assumptions, we present collapsed Gibbs sampling algorithms for the generalized relational topic models by exploring data augmentation without making restricting assumptions. Under the generic RegBayes framework, we carefully investigate two popular discriminative loss functions, namely, the logistic log-loss and the max-margin hinge loss. Experimental results on several real network datasets demonstrate the significance of these extensions on improving prediction performance.

  16. A logic road from special relativity to general relativity

    OpenAIRE

    Andréka, Hajnal; Madarász, Judit X.; Németi, István; Székely, Gergely

    2010-01-01

    We present a streamlined axiom system of special relativity in first-order logic. From this axiom system we "derive" an axiom system of general relativity in two natural steps. We will also see how the axioms of special relativity transform into those of general relativity. This way we hope to make general relativity more accessible for the non-specialist.

  17. Uruguay in International Relations

    Directory of Open Access Journals (Sweden)

    Anton Sergeevich Andreev

    2015-12-01

    Full Text Available This article analyzes the foreign policy of the leftist government of Uruguay at the beginning of the XXI century. Latin America is an important actor in the process of creating a multipolar world, and Uruguay becomes one of the political and economic centers of the continent. One of the important political processes in South America is a regional integration which has many forms. This article shows the main areas of Uruguay diplomacy in various integration formations of the region. Based on the analysis of the program of the third government of “Broad Front” article shows the goals and objectives of the country in the processes of regional integration, the problems and prospects of these processes. The author notes that the Government of Uruguay is looking for creating common political and economic institutions for the united Latin American continent. In the new political and economic conditions Uruguay becomes important partner for the BRICS countries as well as for the EU and the United States. The article shows the prospects for Uruguay in the BRICS in the context of changing the place of developing countries in the architecture of the global world, as well as in the context of the participation of ex-President Jose Mujica in the BRICS summit 2014. Currently, Uruguay is standing in front of a political choice, because the country has people who want the development of relations with the United States as economic partner and political center of the region. Also in Uruguay are supporters of the development of relations with the EU. The paper shows the tasks and objectives of Uruguay's foreign policy towards the US and the EU, as well as a place of Uruguay in the foreign policy of major actors of international relations. The article says the prospects for the foreign policy of Uruguay in the context of the presidential and parliamentary elections in 2014, a new government and the conservation status of Uruguay as a country of “left turn

  18. Work related shoulder disorders

    DEFF Research Database (Denmark)

    Svendsen, Susanne Wulff; Bonde, Jens Peter; Mathiassen, S.E.

    2004-01-01

    and symptoms. Data were analysed by generalised estimating equation and multiple logistic regression with adjustment for potential confounders. Results: For current upper arm elevation above 90°, a duration increment of 1% of the daily working hours was associated with odds ratios of 1.23 (95% CI 1.10 to 1......Aims: To determine quantitative exposure-response relations between work with highly elevated arms and supraspinatus tendinitis, shoulder pain with disability, and shoulder pain without disability. Methods: A cross sectional study was conducted in a historical cohort of 1886 males from three...... occupational groups. Exposure measurements were performed for four consecutive working days in a random sample of 72 currently employed subjects. Individual work histories were obtained by questionnaire and register data. Health status was ascertained by physical examination blinded towards exposure...

  19. Sleep-related laryngospasm

    Directory of Open Access Journals (Sweden)

    Flavio S. Aloe

    1995-03-01

    Full Text Available Seven patients (mean age 46.6; range 33-58; 6M.1F presented with sleep-related choking episodes and were found to have features in common that distinguished them from other known causes of choking episodes during sleep. The characteristic features include: an awakening from sleep with an acute choking sensation, stridor, panic, tachycardia, short duration of episode Gess than 60 seconds, infrequent episodes (typically less than 1 per month, and absence of any known etiology. The disorder most commonly occurs in middle-aged males who are otherwise healthy. In one patient an episode of laryngospasm was polysomnographically documented to occur during stage 3. The clinical features and the polysomnographic findings suggest spasm of the vocal cords of unknown etiology.

  20. Analysing international relations

    DEFF Research Database (Denmark)

    Corry, Olaf

    2014-01-01

    matters by depicting reality in new ways. I then show how different theories rely on different ‘pictures’ of what makes up the international system. Section 2 shows how theories differ in terms of their scope, their aims and their purposes. Section 3 explores some of the choices to be made when using...... theories to ‘explain’ international relations and distinguishes between different kinds of explanation. In Section 4 I look at how different theories have been grouped – first according to their underlying views of what is valid knowledge, and second in terms of different accounts of how history works.......Presented with conflicting evidence and interpretations, how do we ever come to valid conclusions about complex questions of continuity and change in global politics? In any analytical task you need to consider a number of things and this final chapter will take you through some of them including...

  1. Introduction to general relativity

    CERN Document Server

    Parthasarthy, R

    2016-01-01

    INTRODUCTION TO GENERAL RELATIVITY begins with a description of the geometry of curved space, explaining geodesics, parallel transport, covariant differentiation, geodesic deviation and spacetime symmetry by killing vectors. It then introduces Einstein's theory of gravitation followed by Schwarzschild solution with its relevance to Positive Mass theorem. The three tests for Einstein's gravity are explained. Other exact solutions such as Vaidya, Kerr and Reisner - Nordstrom metric are included. In the Chapter on cosmological solutions, a detailed description of Godel metric is provided. It then introduces five dimensional spacetime of Kaluza showing the unification of gravity with electromagnetism. This is extended to include non-Abelian gauge theory by invoking compact extra dimensions. Explicit expressions in this case for Christoffel connections and ricci tensor are derived and the higher dimensional gravity action is shown to compactification are given.

  2. Amphetamine derivative related deaths.

    Science.gov (United States)

    Lora-Tamayo, C; Tena, T; Rodríguez, A

    1997-02-28

    Amphetamine its methylendioxy (methylendioxyamphetamine methylenedioxymethylamphetamine, methylenedioxyethylamphetamine) and methoxy derivatives (p-methoxyamphetamine and p-methoxymethylamphetamine) are widely abused in Spanish society. We present here the results of a systematic study of all cases of deaths brought to the attention of the Madrid department of the Instituto Nacional de Toxicologia from 1993 to 1995 in which some of these drugs have been found in the cadaveric blood. The cases were divided into three categories: amphetamine and derivatives, amphetamines and alcohol, amphetamines and other drugs. Data on age, sex, clinical symptoms, morphological findings, circumstances of death, when known, and concentration of amphetamine derivatives, alcohol and other drugs in blood are given for each group. The information provided here may prove to be useful for the forensic interpretation of deaths which are directly or indirectly related to abuse of amphetamine derivatives.

  3. Communication and external relations

    International Nuclear Information System (INIS)

    2002-01-01

    A company's identity is what it really is, whereas its image is what others perceive or think it is. Therefore, it should suffice to simply combine these two concepts-identity and image-to simplify communication activities. However, identity and image are complex, varying concepts that are conditioned by environment, opinions, expectations, attitudes, market evolution and many other factors. In Cofrentes, we have always been aware of the difficulties involved in successful communication at all levels and, therefore, from the very beginning, even before the Plant was started up, channels were established for public service and relations with all the entities of Cofrentes NPP physical, human and institutional environment in its three possible spheres of influence at the local, provincial and national levels. (Author)

  4. Research as relational agency

    DEFF Research Database (Denmark)

    Hasse, Cathrine

    2017-01-01

    the agency of iPads implemented in Danish schools challenged the implementation of a research based auxiliary artefact, the TECS-model, meant to help teachers managing teaching with iPads in Danish schools. Researchers had to develop a special sensitivity to the cultural force of all of these artefacts......Studying the impact of educational technologies ‘in the wild’ put new demands on researchers than when researchers are conducting experiments in a laboratory. When researchers work within institutional boundaries they cannot take for granted that all members engaged in institutional work share...... the same conception of material artefacts, which are non-human in the sense that they are not just material but agentic and persuasive like humans. Local conceptualisations of artefacts must be explored as the researchers develop relational agency with the different local people involved. New educational...

  5. Strains in general relativity

    International Nuclear Information System (INIS)

    Bini, Donato; Felice, Fernando de; Geralico, Andrea

    2006-01-01

    The definition of relative accelerations and strains among a set of comoving particles is studied in connection with the geometric properties of the frame adapted to a 'fiducial observer'. We find that a relativistically complete and correct definition of strains must take into account the transport law of the chosen spatial triad along the observer's congruence. We use special congruences of (accelerated) test particles in some familiar spacetimes to elucidate such a point. The celebrated idea of Szekeres' compass of inertia, arising when studying geodesic deviation among a set of free-falling particles, is here generalized to the case of accelerated particles. In doing so we have naturally contributed to the theory of relativistic gravity gradiometer. Moreover, our analysis was made in an observer-dependent form, a fact that would be very useful when thinking about general relativistic tests on space stations orbiting compact objects like black holes and also in other interesting gravitational situations

  6. Poland- Ukraine Relations

    Directory of Open Access Journals (Sweden)

    Andrzej Szeptycki

    2016-01-01

    Full Text Available Poland and Ukraine are the two biggest and most populated countries of Central and Eastern Europe. Because of their size, neighbourhood and position in the region the two countries have often been compared to France and Germany. Both countries are deeply interested in their mutual cooperation. Such situation steams from five factors: direct neighbourhood, common (albeit difficult history, attractiveness of the Polish labour market for the Ukrainians, membership of Poland in the Western structures, and last but not least, the Russian threat. Despite complimentary interests, both countries have difficulty to effectively develop their mutual relations and turn them into a real “strategic partnership”. These problems are due to the internal political and economic situation in Ukraine, limits imposed by the membership of Poland in the EU, Russian policy aiming at keeping Ukraine within its zone of influence and, finally, the EU reluctance to effectively engage in Ukraine.

  7. Fuel related risks; Braenslerisker

    Energy Technology Data Exchange (ETDEWEB)

    Englund, Jessica; Sernhed, Kerstin; Nystroem, Olle; Graveus, Frank (Grontmij AB, (Sweden))

    2012-02-15

    The project, within which this work report was prepared, aimed to complement the Vaermeforsk publication 'Handbook of fuels' on fuel related risks and measures to reduce the risks. The fuels examined in this project where the fuels included in the first version of the handbook from 2005 plus four additional fuels that will be included in the second and next edition of the handbook. Following fuels were included: woodfuels (sawdust, wood chips, powder, briquettes), slash, recycled wood, salix, bark, hardwood, stumps, straw, reed canary grass, hemp, cereal, cereal waste, olive waste, cocoa beans, citrus waste, shea, sludge, forest industrial sludge, manure, Paper Wood Plastic, tyre, leather waste, cardboard rejects, meat and bone meal, liquid animal and vegetable wastes, tall oil pitch, peat, residues from food industry, biomal (including slaughterhouse waste) and lignin. The report includes two main chapters; a general risk chapter and a chapter of fuel specific risks. The first one deals with the general concept of risk, it highlights laws and rules relevant for risk management and it discuss general risks that are related to the different steps of fuel handling, i.e. unloading, storing, processing the fuel, transportation within the facility, combustion and handling of ashes. The information that was used to produce this chapter was gathered through a literature review, site visits, and the project group's experience from risk management. The other main chapter deals with fuel-specific risks and the measures to reduce the risks for the steps of unloading, storing, processing the fuel, internal transportation, combustion and handling of the ashes. Risks and measures were considered for all the biofuels included in the second version in the handbook of fuels. Information about the risks and risk management was gathered through interviews with people working with different kinds of fuels in electricity and heat plants in Sweden. The information from

  8. Antioxidant and enzymatic responses to oxidative stress induced by pre-harvest water supply reduction and ripening on mango (Mangifera indica L. cv. 'Cogshall') in relation to carotenoid content.

    Science.gov (United States)

    Rosalie, Rémy; Joas, Jacques; Deytieux-Belleau, Christelle; Vulcain, Emmanuelle; Payet, Bertrand; Dufossé, Laurent; Léchaudel, Mathieu

    2015-07-20

    The effects of a reduction in water supply during fruit development and postharvest fruit ripening on the oxidative status and the antioxidant defense system were studied in the mango fruit (Mangifera indica L.) cv. Cogshall. Changes in non-enzymatic (ascorbate) and enzymatic (SOD, CAT, APX, MDHAR, DHAR and GR) antioxidants, as well as oxidative parameters (H2O2 and MDA) and major carotenoids, were measured in unripe and ripe fruits from well-irrigated and non-irrigated trees. Under non-limiting water supply conditions, ripening induced oxidation as a result of the production of ROS and decreased ascorbate content. Antioxidant enzymatic systems were activated to protect fruit tissues and to regenerate the ascorbate pool. The carotenoid pool, mainly represented by β-carotene and esterified violaxanthine isomers, accumulated naturally during mango ripening. The suppression of irrigation decreased fruit size and induced accumulation of ABA and of its storage form, ABA-GE, in fruit pulp from the earliest harvest. It also increased oxidation, which was observable by the high levels of ascorbate measured at the early stages at harvest, and by the delay in the time it took to reach the pseudo constant carotene-to-xanthophyll ratio in ripe fruits. Nevertheless, differences between the irrigation treatments on the antioxidant system in ripe fruits were not significant, mainly because of the drastic changes in this system during ripening. Copyright © 2015 Elsevier GmbH. All rights reserved.

  9. Superconcentration and related topics

    CERN Document Server

    Chatterjee, Sourav

    2014-01-01

    A certain curious feature of random objects, introduced by the author as “super concentration,” and two related topics, “chaos” and “multiple valleys,” are highlighted in this book. Although super concentration has established itself as a recognized feature in a number of areas of probability theory in the last twenty years (under a variety of names), the author was the first to discover and explore its connections with chaos and multiple valleys. He achieves a substantial degree of simplification and clarity in the presentation of these findings by using the spectral approach. Understanding the fluctuations of random objects is one of the major goals of probability theory and a whole subfield of probability and analysis, called concentration of measure, is devoted to understanding these fluctuations. This subfield offers a range of tools for computing upper bounds on the orders of fluctuations of very complicated random variables. Usually, concentration of measure is useful when more direct prob...

  10. Stakeholder Relations Office

    CERN Multimedia

    2013-01-01

    Scientists, politicians, the public, school children, our neighbours, you. All of these groups of people have a stake in CERN, and all are important to us.   The list of stakeholders in an organisation as large and complex as CERN is a long and ever lengthening one. Each group has its own specific interests and needs in terms of what kind of information it requires from CERN and how we should engage. It’s important, therefore, for us to ensure that we’re communicating optimally with everyone we care about and who cares about us. This is something that CERN has always taken seriously. The CERN Courier, for example, was first published in 1959 and we had a pro-active public information office right from the start. Today, our stakeholder relations are spread between several groups and teams, reflecting the nature of CERN today. But while we’re already doing a good job, I think we can do better by exploiting the synergies between these teams, and that’s wh...

  11. Sports related to drowning.

    Science.gov (United States)

    Szpilman, David; Orlowski, James P

    2016-09-01

    Aquatic sports are included in the top list of risky practices as the environment per se carries a possibility of death by drowning if not rescued in time. Not only are aquatic sports related to a high risk of death, but also all sports practiced on the water, over the water and on ice. Whatever the reason a person is in the water, drowning carries a higher possibility of death if the individual is unable to cope with the water situation, which may simply be caused by an inability to stay afloat and get out of the water or by an injury or disease that may lead to physical inability or unconsciousness. The competitive nature of sports is a common pathway that leads the sports person to exceed their ability to cope with the environment or simply misjudge their physical capability. Drowning involves some principles and medical interventions that are rarely found in other medical situations as it occurs in a deceptively hostile environment that may not seem dangerous. Therefore, it is essential that health professionals are aware of the complete sequence of action in drowning. This article focuses on the pulmonary injury in sports and recreational activities where drowning plays the major role. Copyright ©ERS 2016.

  12. Relative Critical Points

    Directory of Open Access Journals (Sweden)

    Debra Lewis

    2013-05-01

    Full Text Available Relative equilibria of Lagrangian and Hamiltonian systems with symmetry are critical points of appropriate scalar functions parametrized by the Lie algebra (or its dual of the symmetry group. Setting aside the structures – symplectic, Poisson, or variational – generating dynamical systems from such functions highlights the common features of their construction and analysis, and supports the construction of analogous functions in non-Hamiltonian settings. If the symmetry group is nonabelian, the functions are invariant only with respect to the isotropy subgroup of the given parameter value. Replacing the parametrized family of functions with a single function on the product manifold and extending the action using the (coadjoint action on the algebra or its dual yields a fully invariant function. An invariant map can be used to reverse the usual perspective: rather than selecting a parametrized family of functions and finding their critical points, conditions under which functions will be critical on specific orbits, typically distinguished by isotropy class, can be derived. This strategy is illustrated using several well-known mechanical systems – the Lagrange top, the double spherical pendulum, the free rigid body, and the Riemann ellipsoids – and generalizations of these systems.

  13. Malnutrition related deaths.

    Science.gov (United States)

    Sparre-Sørensen, Maja; Kristensen, Gustav N

    2016-10-01

    Studies have shown that malnutrition increases the risk of morbidity, mortality, the length of hospital stay, and costs in the elderly population. Approximately one third of all patients admitted to geriatric wards in Denmark are malnourished according to the Danish Geriatric database. The aim of this study is to describe and examine the sudden increase in deaths due to malnutrition in the elderly population in Denmark from 1999 and, similarly, the sudden decline in malnutrition related deaths in 2007. A descriptive epidemiologic study was performed. All Danes listed in the national death registry who died from malnutrition in the period from 1994 to 2012 are included. The number of deaths from malnutrition increased significantly during the period from 1999 to 2007, especially in the age group 70 years and over. Additionally, we document a surprising similarity between the development in excess mortality from malnutrition in the five Danish regions during the same period. During the period 1999-2007 malnutrition was the direct cause of 340 extra deaths, and probably ten times more registered under other diseases. This development in excess mortality runs parallel in all five Danish regions over time. Copyright © 2016 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

  14. [Work-related COPD].

    Science.gov (United States)

    Fell, Anne Kristin Møller; Aasen, Tor Olav Brøvig; Kongerud, Johny

    2014-11-01

    Work-related COPD occurs as a result of exposure to harmful particles and gases/fumes in the workplace, including among non-smokers. The objective of this article is to present more recent findings on the correlation between occupational exposure and COPD. In addition, we review diagnostic and prognostic considerations and the potential for prevention. We have undertaken literature searches in Medline and EMBASE for the period May 2009 - July 2014. Studies without any measurements of pulmonary function or references to occupational exposure were excluded. We have also included three prospective studies on pulmonary function and occupational exposure that were not indexed with the search terms used for obstructive pulmonary disease. Three population studies and eight studies that described a specific industry or sector were included. Recent studies detect an association between exposure and an increased risk of COPD in the construction industry, metallurgical smelting, cement production and the textile industry. In other respects, the findings from previous review studies are confirmed. Exposure to a number of organic and inorganic particles and fumes in the workplace may cause COPD even at prevailing levels of exposure. Doctors should inquire about such exposure in cases of suspected and established COPD and should have a low threshold for referral to occupational health assessment.

  15. Geriatic Disability Related Factors

    Directory of Open Access Journals (Sweden)

    Mohsen Adib Hajbagheri

    2008-07-01

    Full Text Available Objectives: Reports are indicating of increasing trend of aging and disability in the developing countries while such disabilities are decreasing within the developed countries. This study designed to evaluate the disability and some of its related factors among the elderly population (65 and older in Kashan, Iran. Methods & Materials: A cross-sectional analytical study was conducted on a multi-stage random sample of 350 elderly people (65 year and older in Kashan. The WHO-DAS-II was used as the generic disability measure. The questionnair had 48 questions. The range of score could be between 0-144. Chi-square, t-test analysis and ANOVA were utilized to check significant differences between subgroups. Results: 61% were men and 12% were living lonely. One fourth had some type of addiction, the majority were ilitrate and two thired had not regular phisycal activity.Twenty percent of the old people had a modereate disability and 4.3% were extremely disabled. A significant relationship was found between the disability and variables such as sex, age, living style, needing help, marriage status, living location, addiction, job, level of physical activity, education, and having multiple diseases. Conclusion: In conclusion, geriatric population in Iran, has a lower levels of disability in compare to those of other developed countries. Need of geriatric cares must be be increasing, since the populationpattern of elderly people is increasing in Iran. Female and ilitrate elders were sufering of more disability. These findings indicated the nessesity to more attention to these voulnarable subgroups of population.

  16. Dispersion relation and relative intensity for double-plasmon satellites

    International Nuclear Information System (INIS)

    Srivastava, K.S.; Shiv Singh; Harsh, O.K.

    1981-01-01

    An expression for the dispersion relation and the relative intensity of double-plasmon oscillations and satellites has been derived by extending the dispersion relation and the extended Bohm and Pines Hamiltonian to second order. The calculated value of the relative intensity of the double-plasmon satellite for Be agrees fairly well with the value observed experimentally by other workers. (orig.)

  17. Is there a map between Galilean relativity and special relativity?

    OpenAIRE

    Shariati, Ahmad; Jafari, N.

    2014-01-01

    Mandanici has provided a map which he claims to be a two way map between Galilean relativity and special relativity. We argue that this map is simply a curvilinear coordinate system on a subset of the two-dimensional Minkowski space-time, and is not a two way map between 1+1 dimensional Galilean relativity and 1+1 dimensional special relativity.

  18. Fault-Related Sanctuaries

    Science.gov (United States)

    Piccardi, L.

    2001-12-01

    Beyond the study of historical surface faulting events, this work investigates the possibility, in specific cases, of identifying pre-historical events whose memory survives in myths and legends. The myths of many famous sacred places of the ancient world contain relevant telluric references: "sacred" earthquakes, openings to the Underworld and/or chthonic dragons. Given the strong correspondence with local geological evidence, these myths may be considered as describing natural phenomena. It has been possible in this way to shed light on the geologic origin of famous myths (Piccardi, 1999, 2000 and 2001). Interdisciplinary researches reveal that the origin of several ancient sanctuaries may be linked in particular to peculiar geological phenomena observed on local active faults (like ground shaking and coseismic surface ruptures, gas and flames emissions, strong underground rumours). In many of these sanctuaries the sacred area is laid directly above the active fault. In a few cases, faulting has affected also the archaeological relics, right through the main temple (e.g. Delphi, Cnidus, Hierapolis of Phrygia). As such, the arrangement of the cult site and content of relative myths suggest that specific points along the trace of active faults have been noticed in the past and worshiped as special `sacred' places, most likely interpreted as Hades' Doors. The mythological stratification of most of these sanctuaries dates back to prehistory, and points to a common derivation from the cult of the Mother Goddess (the Lady of the Doors), which was largely widespread since at least 25000 BC. The cult itself was later reconverted into various different divinities, while the `sacred doors' of the Great Goddess and/or the dragons (offspring of Mother Earth and generally regarded as Keepers of the Doors) persisted in more recent mythologies. Piccardi L., 1999: The "Footprints" of the Archangel: Evidence of Early-Medieval Surface Faulting at Monte Sant'Angelo (Gargano, Italy

  19. Public Relations and Interpersonal Communication.

    Science.gov (United States)

    Lance, Elizabeth P.

    Despite a lack of consensus on theoretical perspectives on public relations and variations in the ways it and interpersonal communication are defined, public relations may be related to interpersonal communication in three ways: (1) it is two-way communication, (2) it is personal, and (3) it is relational. Even in activities having the highest…

  20. Distortions in Judged Spatial Relations.

    Science.gov (United States)

    Stevens, Albert

    1978-01-01

    Distortions in judgments of relative geographical relations were observed, particularly when the locations were in different geographical or political units. Subjects distorted the judged relation to conform with the relation of the superordinate political unit. A model for the hierachical storage of spatial information is presented. (Author/RD)

  1. Perceptions of Public Relations Education.

    Science.gov (United States)

    Stacks, Don W.; Botan, Carl; Turk, Judy VanSlyke

    1999-01-01

    Surveys 258 public-relations educators and practitioners, finding they agree that public-relations education is on track; that systematic assessment is an important feature of public-relations education; and that they agreed on how public-relations education should be structured, and demonstrated a high degree of similarity in their preferences…

  2. Are hospitals also for relatives?

    DEFF Research Database (Denmark)

    Nissen, Nina Konstantin; Madsen, Mette; Kjøller, Mette

    2008-01-01

    at relatives of patients with cardiac diseases is sparse. This study aimed to survey the prevalence of health services for relatives of cardiac patients in Denmark. METHODS: We surveyed activities offered by Danish hospitals to the relatives of cardiac patients. Data were obtained from an Internet-based survey...... and 50 of 55 invited hospital departments participated. RESULTS: Almost all departments offer activities to relatives of cardiac patients, but only one-quarter have activities specifically aimed at supporting relatives. Large departments offer activities for relatives more often than smaller departments....... Participation rates for relatives are generally low, and the departments experience numerous barriers in providing activities for relatives of heart patients. CONCLUSIONS: Danish hospitals focus very little on relatives of cardiac patients, and this seems to be due to several factors, including lack...

  3. A Relational Algebra Query Language for Programming Relational Databases

    Science.gov (United States)

    McMaster, Kirby; Sambasivam, Samuel; Anderson, Nicole

    2011-01-01

    In this paper, we describe a Relational Algebra Query Language (RAQL) and Relational Algebra Query (RAQ) software product we have developed that allows database instructors to teach relational algebra through programming. Instead of defining query operations using mathematical notation (the approach commonly taken in database textbooks), students…

  4. Dynamics of relative motion of test particles in general relativity

    International Nuclear Information System (INIS)

    Bazanski, S.L.

    1977-01-01

    Several variational principles which lead to the first and the second geodesic deviation equations, recently formulated by the author and used for the description of the relative motion of test particles in general relativity are presented. Relations between these principles are investigated and exhibited. The Hamilton-Jacobi equation is also studied for these generalized deviations and the conservation laws appearing here are discussed

  5. Projective relativity, cosmology and gravitation

    International Nuclear Information System (INIS)

    Arcidiacono, G.

    1986-01-01

    This book describes the latest applications of projective geometry to cosmology and gravitation. The contents of the book are; the Poincare group and Special Relativity, the thermodynamics and electromagnetism, general relativity, gravitation and cosmology, group theory and models of universe, the special projective relativity, the Fantappie group and Big-Bang cosmology, a new cosmological projective mechanics, the plasma physics and cosmology, the projective magnetohydrodynamics field, projective relativity and waves propagation, the generalizations of the gravitational field, the general projective relativity, the projective gravitational field, the De Sitter Universe and quantum physics, the conformal relativity and Newton gravitation

  6. Information in relational data bases

    Energy Technology Data Exchange (ETDEWEB)

    Abhyankar, R B

    1982-01-01

    A new knowledge representation scheme is proposed for representing incomplete information in relational data bases. The knowledge representation scheme introduces a novel convention for negative information based on modal logic and a novel data structure obtained by introducing tuple flags in the relational model of data. Standard and minimal forms are defined for relations conforming to the new data structure. The conventional relational operators, select, project and join, the redefined so they can be used to manipulate relations containing incomplete information. Conditions are presented for the lossless decomposition of relations containing incomplete information. 20 references.

  7. Age-related hearing loss

    Science.gov (United States)

    ... grow older. Your genes and loud noise (from rock concerts or music headphones) may play a large role. The following factors contribute to age-related hearing loss: Family history (age-related hearing loss tends to run in ...

  8. Strategi Public Relations Pariwisata Bali

    OpenAIRE

    Cahaya Putra, Kadek Dwi

    2008-01-01

    Abstract: Bali has to maintain its image and reputation as the world leading class tourist destination. Tourism in fact is a vulnerable industry easily ruined by related issues and crises. Therefore, Public Relations (PR) with its communication strategy is highly required to maintain good relationships with related parties. This study is aimed at identifying Bali’s Public Relations positioning and setting up its PR strategies. Data and information are gained by means of questionnaire distri...

  9. Education for Corporate Public Relations.

    Science.gov (United States)

    Baxter, Bill L.

    1985-01-01

    Surveyed members of the Public Relations Society of America who reported that (1) students planning public relations careers in corporations should take courses in this order of priority: journalism, public relations, internships, speech communication, marketing, etc., and (2) an MBA degree was the best advanced education degree. (PD)

  10. Public Relations: Selected, Annotated Bibliography.

    Science.gov (United States)

    Demo, Penny

    Designed for students and practitioners of public relations (PR), this annotated bibliography focuses on recent journal articles and ERIC documents. The 34 citations include the following: (1) surveys of public relations professionals on career-related education; (2) literature reviews of research on measurement and evaluation of PR and…

  11. Relative deprivation and intergroup prejudice

    NARCIS (Netherlands)

    Pettigrew, T.F.; Christ, O.; Wagner, U.; Meertens, R.W.; van Dick, R.; Zick, A.

    2008-01-01

    Using three diverse European surveys, we test the relationship between relative deprivation (RD) and anti-immigrant prejudice. We find that both group relative deprivation (GRD) and individual relative deprivation (IRD) are found primarily among working-class respondents who are politically

  12. Introducing Relativity into Quantum Chemistry

    Science.gov (United States)

    Li, Wai-Kee; Blinder, S. M.

    2011-01-01

    It is not often realized by chemists that the special theory of relativity is behind several aspects of quantum chemistry. The Schrdinger equation itself is based on relations between space-time and energy-momentum four vectors. Electron spin is, of course, the most obvious manifestation of relativity. The chemistry of some heavy elements is…

  13. Representing and querying now-relative relational medical data.

    Science.gov (United States)

    Anselma, Luca; Piovesan, Luca; Stantic, Bela; Terenziani, Paolo

    2018-03-01

    Temporal information plays a crucial role in medicine. Patients' clinical records are intrinsically temporal. Thus, in Medical Informatics there is an increasing need to store, support and query temporal data (particularly in relational databases), in order, for instance, to supplement decision-support systems. In this paper, we show that current approaches to relational data have remarkable limitations in the treatment of "now-relative" data (i.e., data holding true at the current time). This can severely compromise their applicability in general, and specifically in the medical context, where "now-relative" data are essential to assess the current status of the patients. We propose a theoretically grounded and application-independent relational approach to cope with now-relative data (which can be paired, e.g., with different decision support systems) overcoming such limitations. We propose a new temporal relational representation, which is the first relational model coping with the temporal indeterminacy intrinsic in now-relative data. We also propose new temporal algebraic operators to query them, supporting the distinction between possible and necessary time, and Allen's temporal relations between data. We exemplify the impact of our approach, and study the theoretical and computational properties of the new representation and algebra. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Rhetorical relations for information retrieval

    DEFF Research Database (Denmark)

    Lioma, Christina; Larsen, Birger; Lu, Wei

    2012-01-01

    -called discourse structure has been applied successfully to several natural language processing tasks. This work studies the use of rhetorical relations for Information Retrieval (IR): Is there a correlation between certain rhetorical relations and retrieval performance? Can knowledge about a document’s rhetorical...... relations be useful to IR? We present a language model modification that considers rhetorical relations when estimating the relevance of a document to a query. Empirical evaluation of different versions of our model on TREC settings shows that certain rhetorical relations can benefit retrieval effectiveness...

  15. Organization, relational justice and absenteeism.

    Science.gov (United States)

    Stoetzer, Ulrich; Åborg, Carl; Johansson, Gun; Svartengren, Magnus

    2014-01-01

    There is a need for more knowledge on how to manage companies towards healthier and more prosperous organizations with low levels of absenteeism. Relational Justice can be a useful concept when managing such organizations. Organizational factors can help to explain why some companies have relatively low absenteeism rates, even though they are equal to other companies in many other aspects. Previous studies suggest that management may be one important factor. Efficient management may depend on good relations between the leaders and the employees. The concept of Relational Justice is designed to capture these relations. Consequently, a Relational Justice framework may be used to understand why some companies have a low incidence of absenteeism. Managers from a representative body of Swedish companies. Interviews were analyzed to explore whether the items representing the concept of Relational Justice can be used to further understand the strategies, procedures and structures that characterize organizations and management in companies with a low incidence of absenteeism. Strategies, procedures or principles related to Relational Justice were common and highlighted in companies with an incidence of absenteeism. The most frequently occurring factors were; to be treated with kindness and consideration, personal viewpoint considered and to be treated impartially. The results suggested that a Relational Justice framework could be used to increase understanding of the organizational and managerial factors typical for companies with a low incidence of absenteeism. A Relational Justice approach to organizational management may be used to successfully lower absenteeism, change organizations and promote healthy and prosperous companies.

  16. The isentropic relation in plasmas

    International Nuclear Information System (INIS)

    Burm, K T A L

    2004-01-01

    The isentropic relation from gas dynamics relates pressure, density and temperature. The use of this relation may ease the hydrodynamic modelling effort. Characteristic for the isentropic relation is the constant isentropic exponent. The isentropic exponent is also in the case of plasmas a constant as long as the ionization degree is between 5 and 80%. This constant is lower due to the extra degree of freedom which comes with ionization in plasmas. The occurrence of ionization means that plasmas are never isentropic. The isentropic relation itself is therefore adapted here to include plasmas within its concept. From the plasma isentropic relation a further extension is to include viscosity and heating. It is found that all extra non-isentropic inclusions further lower the (quasi-) isentropic exponent in the adapted isentropic relation

  17. Producing and Recognizing Analogical Relations

    Science.gov (United States)

    Lipkens, Regina; Hayes, Steven C

    2009-01-01

    Analogical reasoning is an important component of intelligent behavior, and a key test of any approach to human language and cognition. Only a limited amount of empirical work has been conducted from a behavior analytic point of view, most of that within Relational Frame Theory (RFT), which views analogy as a matter of deriving relations among relations. The present series of four studies expands previous work by exploring the applicability of this model of analogy to topography-based rather than merely selection-based responses and by extending the work into additional relations, including nonsymmetrical ones. In each of the four studies participants pretrained in contextual control over nonarbitrary stimulus relations of sameness and opposition, or of sameness, smaller than, and larger than, learned arbitrary stimulus relations in the presence of these relational cues and derived analogies involving directly trained relations and derived relations of mutual and combinatorial entailment, measured using a variety of productive and selection-based measures. In Experiment 1 participants successfully recognized analogies among stimulus networks containing same and opposite relations; in Experiment 2 analogy was successfully used to extend derived relations to pairs of novel stimuli; in Experiment 3 the procedure used in Experiment 1 was extended to nonsymmetrical comparative relations; in Experiment 4 the procedure used in Experiment 2 was extended to nonsymmetrical comparative relations. Although not every participant showed the effects predicted, overall the procedures occasioned relational responses consistent with an RFT account that have not yet been demonstrated in a behavior-analytic laboratory setting, including productive responding on the basis of analogies. PMID:19230515

  18. The special theory of relativity bound with relativity

    CERN Document Server

    Dingle, Herbert

    2014-01-01

    The Special Theory of Relativity:Based on a short course of lectures delivered in the late 1930s, this short book presents the theory of Special Relativity by formulating a redefinition of the measurement of length, and thus will appeal to students of physics who wish to think through Einstein's thought without the encumbrance of quasi-scientific concepts and language. Relativity: A Very Elementary Exposition:This brief lecture, delivered in October 1921 and published for the first time in 1925, offers an explanation of Einstein's theory of Special Relativity for the non-scientist, giving a ge

  19. Relating Derived Relations as a Model of Analogical Reasoning: Reaction Times and Event-Related Potentials

    Science.gov (United States)

    Barnes-Holmes, Dermot; Regan, Donal; Barnes-Holmes, Yvonne; Commins, Sean; Walsh, Derek; Stewart, Ian; Smeets, Paul M.; Whelan, Robert; Dymond, Simon

    2005-01-01

    The current study aimed to test a Relational Frame Theory (RFT) model of analogical reasoning based on the relating of derived same and derived difference relations. Experiment 1 recorded reaction time measures of similar-similar (e.g., "apple is to orange as dog is to cat") versus different-different (e.g., "he is to his brother as…

  20. The relation between herbivore density and relative resource ...

    African Journals Online (AJOL)

    The relation between kudu density and the relative density of habitat patches in each landscape was significant, with exponential models producing more significant statistics than linear models. Regressions of resource density against animal density are useful to understand 'carrying capacity' for wild herbivores, and ...

  1. How public relations works: theoretical roots and public relations perspectives

    NARCIS (Netherlands)

    Ihlen, Ø.; van Ruler, B.

    2007-01-01

    Public relations is often studied from a managerial, instrumental perspective or a psychological, behavioral perspective. To understand the role of public relations in building trust or mistrust and to develop - or destroy - a license to operate, it needs also to be studied as a social phenomenon.

  2. Relative expression of genes related with cold tolerance in ...

    African Journals Online (AJOL)

    Low temperature is one of the main abiotic stresses affecting rice yield in Chile. Alterations in phenology and physiology of the crop are observed after a cold event. The objective of this work was to study the relative expression of genes related with cold stress in Chilean cultivars of rice. For this, we analyzed the expression ...

  3. The principle of relativity and the special relativity triple

    International Nuclear Information System (INIS)

    Guo Hanying; Wu Hongtu; Zhou Bin

    2009-01-01

    Based on the principle of relativity and the postulate on universal invariant constants (c,l) as well as Einstein's isotropy conditions, three kinds of special relativity form a triple with a common Lorentz group as isotropy group under full Umov-Weyl-Fock-Lorentz transformations among inertial motions

  4. Special Relativity in Week One: 1) The Principle of Relativity

    Science.gov (United States)

    Huggins, Elisha

    2011-01-01

    We like to begin an introductory physics course with a law of physics that applies to everything, has no known exceptions, and whose consequences are already familiar to students. That law is the principle of relativity. By focusing on the principle of relativity itself, and a careful selection of the thought experiments, we can comfortably…

  5. General relativity basics and beyond

    CERN Document Server

    Date, Ghanashyam

    2015-01-01

    A Broad Perspective on the Theory of General Relativity and Its Observable Implications General Relativity: Basics and Beyond familiarizes students and beginning researchers with the basic features of the theory of general relativity as well as some of its more advanced aspects. Employing the pedagogical style of a textbook, it includes essential ideas and just enough background material needed for readers to appreciate the issues and current research. Basics The first five chapters form the core of an introductory course on general relativity. The author traces Einstein’s arguments and presents examples of space-times corresponding to different types of gravitational fields. He discusses the adaptation of dynamics in a Riemannian geometry framework, the Einstein equation and its elementary properties, and different phenomena predicted or influenced by general relativity. Beyond Moving on to more sophisticated features of general relativity, the book presents the physical requirements of a well-defined de...

  6. The Impact of Political Relations Between Countries on Economic Relations

    Directory of Open Access Journals (Sweden)

    Hossein Askari

    2012-09-01

    Full Text Available In this paper, we assess the implications of changes in bilateral diplomatic relations with the United States for economic relations. We identify countries whose relations with the US changed during two historic and significant milestones in the past three decades, and a third group of countries after their leftist governments failed/collapsed in early 1990s. Using the Mann-Whitney U-test, we measure the significance of changes in economic relations. We chose the following set of economic indices to reflect economic relations: imports and exports to and from the US, capital outflows from the US to the country, economic and military assistance provided by the US, flow of students to the US, US arms export to the country, the country’s military expenditures, and believing in the importance of remittances and FDI and portfolio investment we use total figures as we did not have bilateral figures. Our results, though mixed, offer some interesting insights.

  7. Special relativity, electrodynamics, and general relativity from Newton to Einstein

    CERN Document Server

    Kogut, John B

    2018-01-01

    Special Relativity, Electrodynamics and General Relativity: From Newton to Einstein, Second Edition, is intended to teach (astro)physics, astronomy, and cosmology students how to think about special and general relativity in a fundamental, but accessible, way. Designed to render any reader a "master of relativity," everything on the subject is comprehensible and derivable from first principles. The book emphasizes problem solving, contains abundant problem sets, and is conveniently organized to meet the needs of both student and instructor. Fully revised, updated and expanded second edition Includes new chapters on magnetism as a consequence of relativity and electromagnetism Contains many improved and more engaging figures Uses less algebra resulting in more efficient derivations Enlarged discussion of dynamics and the relativistic version of Newton's second law

  8. Violence related to health work

    OpenAIRE

    Juliana da Silva Oliveira; Roberta Laíse Gomes Leite Morais; Elisama Nascimento Rocha; Sérgio Donha Yarid; Edite Lago da Silva Sena; Rita Narriman Silva de Oliveira Boery

    2014-01-01

    This study aimed to present a critical and reflective literature review on the violence related to health work. The survey was conducted through an integrated search in the Virtual Health Library in the months of May and June 2011. We selected 24 articles. The reading of the material led us to the following division results: studies characterization and bioethical reflection on violence related to health work. The work-related violence has consequences not only direct on ...

  9. Infinitesimal bundles and projective relativity

    International Nuclear Information System (INIS)

    Evans, G.T.

    1973-01-01

    An intrinsic and global presentation of five-dimensional relativity theory is developed, in which special coordinate conditions are replaced by conditions of Lie invariance. The notion of an infinitesimal bundle is introduced, and the theory of connexions on principal bundles is extended to infinitesimal bundles. Global aspects of projective relativity are studied: it is shown that projective relativity can describe almost any space-time. In particular, it is not necessary to assume that the electromagnetic field have a global potential. (author)

  10. Basic relativity. An introductory essay

    Energy Technology Data Exchange (ETDEWEB)

    Hrasko, Peter [Pecs Univ. (Hungary)

    2011-07-01

    This Brief presents a new way of introducing relativity theory, in which perplexing relativistic effects such as time dilation and Lorentz contraction are explained prior to the discussion of Lorentz-transformation. The notion of relativistic mass is shown to contradict the spirit of relativity theory and the true significance of the mass-energy relation is contrasted with the popular view of it. The author discusses the twin paradox from the point of view of both siblings. Last but not least, the fundamentals of general relativity are described, including the recent Gravity Probe B experiment. (orig.)

  11. Basic relativity. An introductory essay

    International Nuclear Information System (INIS)

    Hrasko, Peter

    2011-01-01

    This Brief presents a new way of introducing relativity theory, in which perplexing relativistic effects such as time dilation and Lorentz contraction are explained prior to the discussion of Lorentz-transformation. The notion of relativistic mass is shown to contradict the spirit of relativity theory and the true significance of the mass-energy relation is contrasted with the popular view of it. The author discusses the twin paradox from the point of view of both siblings. Last but not least, the fundamentals of general relativity are described, including the recent Gravity Probe B experiment. (orig.)

  12. Basic Relativity An Introductory Essay

    CERN Document Server

    Hraskó, Péter

    2011-01-01

    This Brief presents a new way of introducing relativity theory, in which perplexing relativistic effects such as time dilation and Lorentz contraction are explained prior to the discussion of Lorentz-transformation. The notion of relativistic mass is shown to contradict the spirit of relativity theory and the true significance of the mass-energy relation is contrasted with the popular view of it. The author discusses the twin paradox from the point of view of both siblings. Last but not least, the fundamentals of general relativity are described, including the recent Gravity Probe B experiment.

  13. Can coupling constants be related

    International Nuclear Information System (INIS)

    Nandi, Satyanarayan; Ng, Wing-Chiu.

    1978-06-01

    We analyze the conditions under which several coupling constants in field theory can be related to each other. When the relation is independent of the renormalization point, the relation between any g and g' must satisfy a differential equation as follows from the renormalization group equations. Using this differential equation, we investigate the criteria for the feasibility of a power-series relation for various theories, especially the Weinberg-Salam type (including Higgs bosons) with an arbitrary number of quark and lepton flavors. (orig./WL) [de

  14. Geometry of physical dispersion relations

    International Nuclear Information System (INIS)

    Raetzel, Dennis; Rivera, Sergio; Schuller, Frederic P.

    2011-01-01

    To serve as a dispersion relation, a cotangent bundle function must satisfy three simple algebraic properties. These conditions are derived from the inescapable physical requirements that local matter field dynamics must be predictive and allow for an observer-independent notion of positive energy. Possible modifications of the standard relativistic dispersion relation are thereby severely restricted. For instance, the dispersion relations associated with popular deformations of Maxwell theory by Gambini-Pullin or Myers-Pospelov are not admissible. Dispersion relations passing the simple algebraic checks derived here correspond to physically admissible Finslerian refinements of Lorentzian geometry.

  15. Soft Congruence Relations over Rings

    Science.gov (United States)

    Xin, Xiaolong; Li, Wenting

    2014-01-01

    Molodtsov introduced the concept of soft sets, which can be seen as a new mathematical tool for dealing with uncertainty. In this paper, we initiate the study of soft congruence relations by using the soft set theory. The notions of soft quotient rings, generalized soft ideals and generalized soft quotient rings, are introduced, and several related properties are investigated. Also, we obtain a one-to-one correspondence between soft congruence relations and idealistic soft rings and a one-to-one correspondence between soft congruence relations and soft ideals. In particular, the first, second, and third soft isomorphism theorems are established, respectively. PMID:24949493

  16. SUMS Counts-Related Projects

    Data.gov (United States)

    Social Security Administration — Staging Instance for all SUMs Counts related projects including: Redeterminations/Limited Issue, Continuing Disability Resolution, CDR Performance Measures, Initial...

  17. Spatial geometry and special relativity

    DEFF Research Database (Denmark)

    Kneubil, Fabiana Botelho

    2016-01-01

    In this work, it is shown the interplay of relative and absolute entities, which are present in both spatial geometry and special relativity. In order to strengthen the understanding of special relativity, we discuss firstly an instance of geometry and the existence of both frame......-dependent and frame-independent entities. We depart from a subject well known by students, which is the three-dimensional geometric space in order to compare, afterwards, with the treatment of four-dimensional space in the special relativity. The differences and similarities between these two subjects are also...

  18. Team incentives in relational contracts

    International Nuclear Information System (INIS)

    Kvaloey, Ola

    2003-01-01

    Incentive schemes for teams are compared. I ask: under which conditions are relational incentive contracts based on joint performance evaluation, relative performance evaluation and independent performance evaluation self-enforceable. The framework of Che and Yoo (2001) on team incentives is combined with the framework of Baker, Gibbons and Murphy (2002) on relational contracts. In a repeated game between one principal and two agents, I find that incentives based on relative or independent performance are expected to dominate when the productivity of effort is high, while joint performance evaluation dominates when productivity is low. Incentives based on independent performance are more probable if the agents own critical assets. (author)

  19. On the relativity of rotation

    International Nuclear Information System (INIS)

    Gron, O.

    2010-01-01

    The question whether rotational motion is relative according to the general theory of relativity is discussed. Einstein's ambivalence concerning this question is pointed out. In the present article I defend Einstein's way of thinking on this when he presented the theory in 1916. The significance of the phenomenon of perfect inertial dragging in connection with the relativity of rotational motion is discussed. The necessity of introducing an extended model of the Minkowski spacetime, in which a globally empty space is supplied with a cosmic mass shell with radius equal to its own Schwarzschild radius, in order to extend the principle of relativity to accelerated and rotational motion, is made clear.

  20. Cross-Domain Analogies as Relating Derived Relations among Two Separate Relational Networks

    Science.gov (United States)

    Ruiz, Francisco J; Luciano, Carmen

    2011-01-01

    Contemporary behavior analytic research is making headway in analyzing analogy as the establishment of a relation of coordination among common types of trained or derived relations. Previous studies have been focused on within-domain analogy. The current study expands previous research by analyzing cross-domain analogy as relating relations among separate relational networks and by correlating participants' performance with a standard measure of analogical reasoning. In two experiments, adult participants first completed general intelligence and analogical reasoning tests. Subsequently, they were exposed to a computerized conditional discrimination training procedure designed to create two relational networks, each consisting of two 3-member equivalence classes. The critical test was a two-part analogical test in which participants had to relate combinatorial relations of coordination and distinction between the two relational networks. In Experiment 1, combinatorial relations for each network were individually tested prior to analogical testing, but in Experiment 2 they were not. Across both experiments, 65% of participants passed the analogical test on the first attempt. Moreover, results from the training procedure were strongly correlated with the standard measure of analogical reasoning. PMID:21547072

  1. The principle of relativity and the indeterminacy of special relativity

    Science.gov (United States)

    de Abreu, Rodrigo; Guerra, Vasco

    2008-01-01

    This work ends a trilogy devoted to a journey into the foundations of special relativity. The first paper debated the meaning of the constancy of the two-way speed of light and its close relation to the conceptualization of time. The second one addressed the question of the possible constancy of the one-way speed of light and the trivial—but, unfortunately, even now somewhat controversial—question of the compatibility between the assumption of a special system of reference and Einstein's special relativity. The present study deals with the principle of relativity. Its historical evolution is reviewed and a 'weak' formulation is defended. It is emphasized that many assertions usually associated with special relativity, such as the 'relativity of time dilation' and 'relativity of space contraction' are indeed philosophical statements, as it has been established already by several authors in the past. Nonetheless, most teachers and scientists still believe nowadays they are implied by the theory and by the group property of the Lorentz transformation. This is by no means so, as it is reviewed and elucidated with the simple example on space contraction. It is argued that the lack of knowledge of the true value of the one-way speed of light in empty space leaves the theory undetermined. Einstein's special relativity corresponds to a simple and very elegant solution to this problem, allowing the study of relative motion without any concern with the study of absolute motion, which is considered to be superfluous. However, its standard interpretation is minimalist and even misleading. A large number of researchers have discussed this question, mostly within the conventionality of simultaneity thesis. The typical formulation of this thesis provides some new physical insight and points out the problem, but does not solve it. In contrast, it often leads to a labyrinth of difficult language which is herein clarified.

  2. The principle of relativity and the indeterminacy of special relativity

    International Nuclear Information System (INIS)

    Abreu, Rodrigo de; Guerra, Vasco

    2008-01-01

    This work ends a trilogy devoted to a journey into the foundations of special relativity. The first paper debated the meaning of the constancy of the two-way speed of light and its close relation to the conceptualization of time. The second one addressed the question of the possible constancy of the one-way speed of light and the trivial-but, unfortunately, even now somewhat controversial-question of the compatibility between the assumption of a special system of reference and Einstein's special relativity. The present study deals with the principle of relativity. Its historical evolution is reviewed and a 'weak' formulation is defended. It is emphasized that many assertions usually associated with special relativity, such as the 'relativity of time dilation' and 'relativity of space contraction' are indeed philosophical statements, as it has been established already by several authors in the past. Nonetheless, most teachers and scientists still believe nowadays they are implied by the theory and by the group property of the Lorentz transformation. This is by no means so, as it is reviewed and elucidated with the simple example on space contraction. It is argued that the lack of knowledge of the true value of the one-way speed of light in empty space leaves the theory undetermined. Einstein's special relativity corresponds to a simple and very elegant solution to this problem, allowing the study of relative motion without any concern with the study of absolute motion, which is considered to be superfluous. However, its standard interpretation is minimalist and even misleading. A large number of researchers have discussed this question, mostly within the conventionality of simultaneity thesis. The typical formulation of this thesis provides some new physical insight and points out the problem, but does not solve it. In contrast, it often leads to a labyrinth of difficult language which is herein clarified

  3. Universal relation between spectroscopic constants

    Indian Academy of Sciences (India)

    (3) The author has used eq. (6) of his paper to calculate De. This relation leads to a large deviation from the correct value depending upon the extent to which experimental values are known. Guided by this fact, in our work, we used experimentally observed De values to derive the relation between spectroscopic constants.

  4. Making Probabilistic Relational Categories Learnable

    Science.gov (United States)

    Jung, Wookyoung; Hummel, John E.

    2015-01-01

    Theories of relational concept acquisition (e.g., schema induction) based on structured intersection discovery predict that relational concepts with a probabilistic (i.e., family resemblance) structure ought to be extremely difficult to learn. We report four experiments testing this prediction by investigating conditions hypothesized to facilitate…

  5. Action Learning as Relational Practice

    Science.gov (United States)

    Boydell, Tom; Blantern, Chris

    2007-01-01

    In this paper we propose that all knowledge is made through social processes and is political (of the people involved). If one invests in a relational or historical ontology (a philosophical choice) there are implications for the way action learning is practiced. We illuminate some of these "relational practices". We purport that action learning…

  6. Pathfinder: XQuery - The Relational Way

    NARCIS (Netherlands)

    Boncz, Peter; Grust, Torsten; van Keulen, Maurice; Manegold, Stefan; Rittinger, Jan; Teubner, Jens; Boehm, K.; Jensen, C.S.; Haas, L.M.; Kersten, M.L.; Larson, P-K.; Ooi, B.C.

    Relational query processors are probably the best understood (as well as the best engineered) query engines available today. Although carefully tuned to process instances of the relational model (tables of tuples), these processors can also provide a foundation for the evaluation of "alien"

  7. New technologies in public relations

    Directory of Open Access Journals (Sweden)

    Dariusz Tworzydło

    2013-12-01

    Full Text Available The article includes an analysis and presentation of selected examples of communication tools, which are used in companies to create and maintain relationships with internal and external environment. The problems related with definition of public relations were also discussed. The article presents the advantage and negative consequences of the use of modern tools of PR, as well.

  8. Symmetric relations of finite negativity

    NARCIS (Netherlands)

    Kaltenbaeck, M.; Winkler, H.; Woracek, H.; Forster, KH; Jonas, P; Langer, H

    2006-01-01

    We construct and investigate a space which is related to a symmetric linear relation S of finite negativity on an almost Pontryagin space. This space is the indefinite generalization of the completion of dom S with respect to (S.,.) for a strictly positive S on a Hilbert space.

  9. Teaching Special Relativity without Calculus

    Science.gov (United States)

    Ruby, Lawrence

    2009-01-01

    In 2007 many AAPT members received a booklet that is the first chapter of a physics textbook available on a CD. This book espouses the new educational philosophy of teaching special relativity as the first item in the topic of mechanics. Traditionally, special relativity is part of one or more modern physics chapters at the end of the text, and…

  10. Geriatric fall-related injuries.

    African Journals Online (AJOL)

    Conclusion: The majority of geriatric fall-related injuries were due to fall from the same level at home. Assessment of risk fac- tors for falls including home hazards is essential for prevention of geriatric fall-related injuries. Keywords: Accidental fall, geriatrics, injury, trauma registry. DOI: http://dx.doi.org/10.4314/ahs.v16i2.24.

  11. Internationalizing the Public Relations Curriculum.

    Science.gov (United States)

    Taylor, Maureen

    2001-01-01

    Discusses broadening public relations to an international level by incorporating the topics of culture, international practices, and culturally sensitive theory development. Discusses rationale, design, and execution of an undergraduate course in international public relations. Suggests ways to incorporate assignments addressing international…

  12. New relations in basic dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Rebigan, F [Institute of Atomic Physics, Bucharest (Romania)

    1995-12-01

    Four new relations have been derived based on the definitions of the fundamental dosimetric quantities given in recent ICRU reports. These relations have the general form A.B=A.B, where A and B are respectively the dosimetric quantities and their rates.

  13. Stakeholder relations and financial performance

    NARCIS (Netherlands)

    Scholtens, B.; Zhou, Y.

    2008-01-01

    We analyze how shareholder performance can be associated with stakeholder relations. As such, we try to find out whether there is an association between financial performance and stakeholder relations with respect to different theoretical notions about the firm. Financial performance is

  14. Evidence logics with relational evidence

    DEFF Research Database (Denmark)

    Baltag, Alexandru; Occhipinti, Andrés

    2017-01-01

    We introduce a family of logics for reasoning about relational evidence: evidence that involves an ordering of states in terms of their relative plausibility. We provide sound and complete axiomatizations for the logics. We also present several evidential actions and prove soundness...

  15. Perempuan Dalam Dunia Public Relations

    OpenAIRE

    Novi Kurnia; I Gusti Ngurah Putra

    2004-01-01

    Literature review shows that women gain more access to job in public relations. Observation in Yogyakarta shows that women are not easily top position in corporation due to understatement of the role of public relations in organizational structure. Discrimination against women is minimal except on family allowance.

  16. Generalized Moshinsky bracket recurrence relations

    International Nuclear Information System (INIS)

    Bevelacqua, J.J.

    1979-01-01

    Recurrence relations for generalized Talmi-Moshinsky brackets are derived. These relations permit the generation of transformation brackets once appropriate starting brackets are determined. The savings in computer time, when compared with generating brackets individually, is at least a factor of 10 for brackets with radial quantum numbers as large as 9 and angular quantum numbers as large as 2. (author)

  17. Finding related functional neuroimaging volumes

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Hansen, Lars Kai

    2004-01-01

    We describe a content-based image retrieval technique for finding related functional neuroimaging experiments by voxelization of sets of stereotactic coordinates in Talairach space, comparing the volumes and reporting related volumes in a sorted list. Voxelization is accomplished by convolving ea...

  18. Perempuan Dalam Dunia Public Relations

    Directory of Open Access Journals (Sweden)

    Novi Kurnia

    2004-03-01

    Full Text Available Literature review shows that women gain more access to job in public relations. Observation in Yogyakarta shows that women are not easily top position in corporation due to understatement of the role of public relations in organizational structure. Discrimination against women is minimal except on family allowance.

  19. Simulation in International Relations Education.

    Science.gov (United States)

    Starkey, Brigid A.; Blake, Elizabeth L.

    2001-01-01

    Discusses the educational implications of simulations in international relations. Highlights include the development of international relations simulations; the role of technology; the International Communication and Negotiation Simulations (ICONS) project at the University of Maryland; evolving information technology; and simulating real-world…

  20. LOCAL GOVERNMENT AND INTERGOVERNMENTAL RELATIONS ...

    African Journals Online (AJOL)

    GRACE

    issues of tax jurisdiction, revenue allocation, intergovernmental relations ... The 1999 Nigeria constitution stipulates the functions and powers of the ... systems of government, is characterized with diverse ethnic groups, ... states perceived to be an attempt by the federal government to relate directly to ..... excise taxes on oil.

  1. Relational Research and Organisation Studies

    DEFF Research Database (Denmark)

    Madsen, Charlotte Øland; Larsen, Mette Vinther; Hansen, Lone Hersted

    , analyzing organizational dialoguing, and polyphonic future-forming ways of writing up research.  Relational Research and Organisation Studies does not only present and discuss guidelines for practice at a onto-epistemological level but also presents and discusses concrete cases of research projects building...... on relational constructionist ideas. Furthermore, excerpts of data are presented and analyzed in order to explain the co-constructed processes of the inquiries more in detail. Relational Research and Organisation Studies invites the reader into the process of planning and carrying out relational constructionist......This volume lays out a variety of ways of engaging in research projects focused on exploring the everyday relational practices of organizing and leading is presented. The main focus is through elaborate examples from the author’s own research to further the understanding of how it is possible...

  2. Sleep-related movement disorders.

    Science.gov (United States)

    Merlino, Giovanni; Gigli, Gian Luigi

    2012-06-01

    Several movement disorders may occur during nocturnal rest disrupting sleep. A part of these complaints is characterized by relatively simple, non-purposeful and usually stereotyped movements. The last version of the International Classification of Sleep Disorders includes these clinical conditions (i.e. restless legs syndrome, periodic limb movement disorder, sleep-related leg cramps, sleep-related bruxism and sleep-related rhythmic movement disorder) under the category entitled sleep-related movement disorders. Moreover, apparently physiological movements (e.g. alternating leg muscle activation and excessive hypnic fragmentary myoclonus) can show a high frequency and severity impairing sleep quality. Clinical and, in specific cases, neurophysiological assessments are required to detect the presence of nocturnal movement complaints. Patients reporting poor sleep due to these abnormal movements should undergo non-pharmacological or pharmacological treatments.

  3. Employment relations, flexibility and risk

    DEFF Research Database (Denmark)

    Jensen, Carsten Strøby

    Employment relations literature often distinguishes between social democratic/corporatist models of employment relations and liberal models of employment relations as they are seen as opposite or at least different ways of organizing labor markets. They are often characterized as having very...... different risk profiles in terms of relationships between employees, employers, and the state. Low levels of labor market regulation very often characterize the liberal models of employment relations as we know them from, for instance, the USA and the UK. This means that employment conditions are very often...... insecure and that the burden of unemployment risk mostly lies with the employees rather than the employer. Corporatist – or social democratic – employment relations models are, in contrast to the liberal models, often characterized by stricter regulation of the labor market and by high standards...

  4. Think Piece: Pioneers as Relational Subjects? Probing Relationality ...

    African Journals Online (AJOL)

    therefore offers a possible framework for more detailed empirical studies on relationality in collective learning .... pioneers. This idea is also reflected in a book co-authored by Hermansen called Commonities ..... studies. Harvard MS: Harvard.

  5. Relationalism or why diplomats find international relations theory strange

    DEFF Research Database (Denmark)

    Adler-Nissen, Rebecca

    2015-01-01

    In this conclusion, which reflects critically on the relational approach to diplomacy and its wider consequences, I argue that diplomats are estranged from IR theory and vice versa - because International Relations scholars generally subscribe to substantialism, whereas diplomats tend to think...... by diplomatic scholars). Relationalism takes as its point of departure the idea that social phenomena making up world politics always develop in relation to other social phenomena. Thus, for example, states are not born into' this world as fully developed states that then "exist"; states are made in continuous...... scholarship and diplomatic knowledge and practice are important for how we understand (and construct) world politics, including war, international cooperation, and responses to human and natural catastrophes....

  6. The Historiography of Public Relations in Turkish Public Relations Books

    OpenAIRE

    KARAASLAN ŞANLI, Halise

    2017-01-01

    Criticism on the hegemonic history of public relations (PR) paved the way for the emergence of new approaches to the historiography of PR. The most significant of such approaches is the exposure of genuine history of PR for each country, taking into account the specific socioeconomic and cultural context of each country. This study focuses on the handling of the history of PR in Turkish books on public relations published by prominent publishing houses in Turkey between 1967 and 2013. The stu...

  7. The Principle of Relativity and the Indeterminacy of Special Relativity

    Science.gov (United States)

    de Abreu, Rodrigo; Guerra, Vasco

    2008-01-01

    This work ends a trilogy devoted to a journey into the foundations of special relativity. The first paper debated the meaning of the constancy of the two-way speed of light and its close relation to the conceptualization of time. The second one addressed the question of the possible constancy of the one-way speed of light and the trivial--but,…

  8. Variations of relative humidity in relation to meningitis in Africa

    Science.gov (United States)

    Seefeldt, M. W.; Hopson, T. M.

    2011-12-01

    The meningitis belt is a region covering Sub-Saharan Africa from the Sahel of West Africa eastward to western Ethiopia. The region is prone to meningitis epidemics during the dry season extending from approximately January to May, depending on the region. Relative humidity has been found to be a critical environmental factor indicating the susceptibility of a region to meningitis epidemics. This study evaluates the variation of relative humidity across West Africa over 30 dry-seasons (1979 - 2009) using the NASA-MERRA dataset. The method of self-organizing maps is employed to characterize the changes in relative humidity patterns across the region within a given dry season as well as changes over the 30 years. A general pattern of changes in relative humidity is indicated as the rainbelt retreats to the south at the onset of the dry season and then returns to the region at the end of the dry season. Within each dry season there is a unique pattern. The climatological conditions of relative humidity at the onset of the dry season provide an indication of the moisture environment for the entire dry season. Year to year variation in the relative humidity patterns are found to be gradual. Future applications involve using the results from the SOM evaluation to be used for future decisions involving prevention of meningitis epidemics.

  9. To understand relativity. 4. ed.

    International Nuclear Information System (INIS)

    Berthon, M.E.

    1995-01-01

    This book comprises three parts: the first one is about the restricted relativity theory with ten chapters which are from Galilee to Newton, tools of classical physics, relativity principle, a dreadful child: light, Michelson experience, the restricted relativity and Einstein postulates (1905), Lorentz transformation, relativistic kinematics, Minkowski time-space, and the relativistic dynamics; the second part concerns the general relativity and the gravitation, from chapter 11 to chapter 19, which are towards the general relativity, absolute acceleration has no sense, the equivalence principle, the principle of generalised relativity, the gravitation and the problems that it formulates, non euclidean theory of the gravitation field, the theory of 1915, Gauss coordinates, classical tests of general relativity; in the last and third part are studied the cosmologies with three chapters, the chapter 20 is dedicated to cosmological principle precursors, the chapter 21 is about the modern cosmological models and the last one finishes on that question: universe is it or not finished. (N.C.). 26 refs., 48 figs., 9 appends

  10. Multilevel security for relational databases

    CERN Document Server

    Faragallah, Osama S; El-Samie, Fathi E Abd

    2014-01-01

    Concepts of Database Security Database Concepts Relational Database Security Concepts Access Control in Relational Databases      Discretionary Access Control      Mandatory Access Control      Role-Based Access Control Work Objectives Book Organization Basic Concept of Multilevel Database Security IntroductionMultilevel Database Relations Polyinstantiation      Invisible Polyinstantiation      Visible Polyinstantiation      Types of Polyinstantiation      Architectural Consideration

  11. Relativity a very short introduction

    CERN Document Server

    Stannard, F Russell

    2008-01-01

    Relativity: A Very Short Introduction makes the theory of relativity understandable and accessible. 100 years ago, Einstein's theory of relativity shattered the world of physics. Our comforting Newtonian ideas of space and time were replaced by bizarre and counterintuitive conclusions: if you move at high speed, time slows down, space squashes up and you get heavier; travel fast enough and you could weigh as much as a jumbo jet, be squashed thinner than a CD without feeling a thing - and live forever. And that was just the special theory. With the general theory came even stranger ideas of curved space-time, which changed our understanding of gravity and the cosmos.

  12. Violence related to health work

    Directory of Open Access Journals (Sweden)

    Juliana da Silva Oliveira

    2014-10-01

    Full Text Available This study aimed to present a critical and reflective literature review on the violence related to health work. The survey was conducted through an integrated search in the Virtual Health Library in the months of May and June 2011. We selected 24 articles. The reading of the material led us to the following division results: studies characterization and bioethical reflection on violence related to health work. The work-related violence has consequences not only direct on professionals’ health, but also for the citizen and society as a whole. Make it visible is the first action needed for prevention / control and to promote healthier workplaces.

  13. VIOLENCE RELATED TO HEALTH WORK

    Directory of Open Access Journals (Sweden)

    Juliana da Silva Oliveira

    2014-03-01

    Full Text Available This study aimed to present a critical and reflective literature review on the violence related to health work. The survey was conducted through an integrated search in the Virtual Health Library in the months of May and June 2011. We selected 24 articles. The reading of the material led us to the following division results: studies characterization and bioethical reflection on violence related to health work. The work-related violence has consequences not only direct on professionals’ health, but also for the citizen and society as a whole. Make it visible is the first action needed for prevention / control and to promote healthier workplaces.

  14. Relational competence in teacher education

    DEFF Research Database (Denmark)

    Grams Davy, Sarah

    This paper presents an ongoing research project aiming to develop both a research-based terminology as well as a practical approach to develop the concept of relational competence in Danish teacher education. The current practical part of Danish teacher education operates with three framing...... learning goals for students: Didactics, classroom leadership and relational work. Especially the latter, relational work, lacks in-depth description and definition in order to become a tangible concept based on which teacher students’ professional qualifications can be developed....

  15. Spinning fluids in general relativity

    Science.gov (United States)

    Ray, J. R.; Smalley, L. L.

    1982-01-01

    General relativity field equations are employed to examine a continuous medium with internal spin. A variational principle formerly applied in the special relativity case is extended to the general relativity case, using a tetrad to express the spin density and the four-velocity of the fluid. An energy-momentum tensor is subsequently defined for a spinning fluid. The equations of motion of the fluid are suggested to be useful in analytical studies of galaxies, for anisotropic Bianchi universes, and for turbulent eddies.

  16. Special relativity a first encounter

    CERN Document Server

    Giulini, Domenico

    2005-01-01

    Special relativity provides the foundations of our knowledge of space and time. Without it, our understanding of the world, and its place in the universe, would be unthinkable. This book gives a concise, elementary, yet exceptionally modern, introduction to special relativity. It is a gentle yet serious 'first encounter', in that it conveys a true understanding rather than purely reports the basic facts. Only very elementary mathematical knowledge is needed to master it (basichigh-school maths), yet it will leave the reader with a sound understanding of the subject. Special Relativity: A First

  17. Relating derived relations as a model of analogical reasoning: reaction times and event-related potentials.

    Science.gov (United States)

    Barnes-Holmes, Dermot; Regan, Donal; Barnes-Holmes, Yvonne; Commins, Sean; Walsh, Derek; Stewart, Ian; Smeets, Paul M; Whelan, Robert; Dymond, Simon

    2005-11-01

    The current study aimed to test a Relational Frame Theory (RFT) model of analogical reasoning based on the relating of derived same and derived difference relations. Experiment 1 recorded reaction time measures of similar-similar (e.g., "apple is to orange as dog is to cat") versus different-different (e.g., "he is to his brother as chalk is to cheese") derived relational responding, in both speed-contingent and speed-noncontingent conditions. Experiment 2 examined the event-related potentials (ERPs) associated with these two response patterns. Both experiments showed similar-similar responding to be significantly faster than different-different responding. Experiment 2 revealed significant differences between the waveforms of the two response patterns in the left-hemispheric prefrontal regions; different-different waveforms were significantly more negative than similar-similar waveforms. The behavioral and neurophysiological data support the RFT prediction that, all things being equal, similar-similar responding is relationally "simpler" than, and functionally distinct from, different-different analogical responding. The ERP data were fully consistent with findings in the neurocognitive literature on analogy. These findings strengthen the validity of the RFT model of analogical reasoning and supplement the behavior-analytic approach to analogy based on the relating of derived relations.

  18. Grammatical Constructions as Relational Categories.

    Science.gov (United States)

    Goldwater, Micah B

    2017-07-01

    This paper argues that grammatical constructions, specifically argument structure constructions that determine the "who did what to whom" part of sentence meaning and how this meaning is expressed syntactically, can be considered a kind of relational category. That is, grammatical constructions are represented as the abstraction of the syntactic and semantic relations of the exemplar utterances that are expressed in that construction, and it enables the generation of novel exemplars. To support this argument, I review evidence that there are parallel behavioral patterns between how children learn relational categories generally and how they learn grammatical constructions specifically. Then, I discuss computational simulations of how grammatical constructions are abstracted from exemplar sentences using a domain-general relational cognitive architecture. Last, I review evidence from adult language processing that shows parallel behavioral patterns with expert behavior from other cognitive domains. After reviewing the evidence, I consider how to integrate this account with other theories of language development. Copyright © 2017 Cognitive Science Society, Inc.

  19. LOCAL GOVERNMENT AND INTERGOVERNMENTAL RELATIONS ...

    African Journals Online (AJOL)

    GRACE

    study reveals that intergovernmental relations among the levels of government .... International Journal of Development and Management Review (INJODEMAR) Vol.10 June, 2015 ..... Administrative Science Quarterly, 16 (2): 216-229. Jinadu ...

  20. Modern canonical quantum general relativity

    CERN Document Server

    Thiemann, Thomas

    2007-01-01

    This is an introduction to the by now fifteen years old research field of canonical quantum general relativity, sometimes called "loop quantum gravity". The term "modern" in the title refers to the fact that the quantum theory is based on formulating classical general relativity as a theory of connections rather than metrics as compared to in original version due to Arnowitt, Deser and Misner. Canonical quantum general relativity is an attempt to define a mathematically rigorous, non-perturbative, background independent theory of Lorentzian quantum gravity in four spacetime dimensions in the continuum. The approach is minimal in that one simply analyzes the logical consequences of combining the principles of general relativity with the principles of quantum mechanics. The requirement to preserve background independence has lead to new, fascinating mathematical structures which one does not see in perturbative approaches, e.g. a fundamental discreteness of spacetime seems to be a prediction of the theory provi...

  1. Basic statements of relativity theory

    Directory of Open Access Journals (Sweden)

    Wolfgang Muschik

    2010-04-01

    Full Text Available Some basic statements of relativity theory, starting out with geometry and observers up to Einstein's field equations, are collected in a systematical order without any proof, to serve as a short survey of tools and results.

  2. Cosmological tests of general relativity

    International Nuclear Information System (INIS)

    Hut, P.

    1977-01-01

    It is stated that the general relativity theory could be tested on a cosmological scale by measuring the Hubble constant and the deceleration parameter, if, in addition, everything could be known about the matter filling the universe. If, on the other hand, nothing could be presupposed about the matter content of the universe general relativity could not be tested by measuring any number of time derivatives of the scale factor. But upon making the assumption of a universe filled with non-interacting mixture of non-relativistic matter and radiation general relativity can in principle be tested by measuring the first five derivatives of the scale factor. Some general relations are here presented using this assumption. (author)

  3. LABOUR RELATIONS IN POSTINDUSTRIAL ECONOMY

    Directory of Open Access Journals (Sweden)

    Yuriy Rostislavovitch Chistyakov

    2013-09-01

    Full Text Available The article deals with inadequacy of present-day labour relations in economy. Out of date form of labour relations makes workforce dependable, causes social inequality, prevents economical development. The article gives results of theoretical and empiric research. The mechanism of guaranteed reproduction of labour to be realized as social partnership is offered.Purpose: the purpose is to give critical estimation of present-day labour relations in postindustrial economy.Method of studies: monographic, general theoretic economic analysis, correlation statistic analysisResults: a new modern adequate alternative form of labour relations guarantying the reproduction of labour is introducedField of application: industrial regulation both in economics in general and concrete businesses; motivation of workers.DOI: http://dx.doi.org/10.12731/2218-7405-2013-8-29

  4. Some Pitfalls in Special Relativity

    Science.gov (United States)

    Chai, An-Ti

    1973-01-01

    The problem of observing a collision between two spaceships is utilized to illustrate the misuse of time dilation and length contraction, and the incorrect description of space-time coordinates in special relativity. (Author/DF)

  5. Canada-U.S. Relations

    National Research Council Canada - National Science Library

    Ek, Carl; Fergusson, Ian F; Nunez-Neto, Blas; Clarke, Stephen F; Abel, Amy; Becker, Geoffrey S; Buck, Eugene H; Corn, M. L; Gelb, Bernard A; Gorte, Ross W

    2006-01-01

    .... The early 1990s brought new governments to Ottawa and Washington, and although Canada's Liberal Party emphasized its determination to act independently of the United States when necessary, relations...

  6. Ecoscapes: Geographical Patternings of Relations

    Directory of Open Access Journals (Sweden)

    Aimar Ventsel

    2012-06-01

    Full Text Available Book review of the publication Ecoscapes: Geographical Patternings of Relations. Edited by Gary Backhaus and John Murungi. Lanham, Boulder, New York, Toronto, Oxford, Lexington Books, 2006, xxxiii+241 pp.

  7. Ecoscapes: Geographical Patternings of Relations

    Directory of Open Access Journals (Sweden)

    Aimar Ventsel

    2013-01-01

    Full Text Available Book review of the publication Ecoscapes: Geographical Patternings of Relations. Edited by Gary Backhaus and John Murungi. Lanham, Boulder, New York, Toronto, Oxford, Lexington Books, 2006, xxxiii+241 pp.

  8. Geometrical optics in general relativity

    OpenAIRE

    Loinger, A.

    2006-01-01

    General relativity includes geometrical optics. This basic fact has relevant consequences that concern the physical meaning of the discontinuity surfaces propagated in the gravitational field - as it was first emphasized by Levi-Civita.

  9. Relational Expertise in Participatory Design

    DEFF Research Database (Denmark)

    Dindler, Christian; Iversen, Ole Sejer

    2014-01-01

    This paper positions relation expertise as a core competence in participatory design. It is an expertise that demands the participatory designer to stimulate the emergence of loosely coupled knotworks, and obtain symbiotic agreement between participants disregarding their professional and social...

  10. Stressful social relations and mortality

    DEFF Research Database (Denmark)

    Lund, Rikke; Christensen, Ulla; Nilsson, Charlotte Juul

    2014-01-01

    BACKGROUND: Few studies have examined the relationship between stressful social relations in private life and all-cause mortality. OBJECTIVE: To evaluate the association between stressful social relations (with partner, children, other family, friends and neighbours, respectively) and all...... men and women aged 36-52 years, linked to the Danish Cause of Death Registry for information on all-cause mortality until 31 December 2011. Associations between stressful social relations with partner, children, other family, friends and neighbours, respectively, and all-cause mortality were examined....... CONCLUSIONS: Stressful social relations are associated with increased mortality risk among middle-aged men and women for a variety of different social roles. Those outside the labour force and men seem especially vulnerable to exposure....

  11. Issues related to geothermal development

    International Nuclear Information System (INIS)

    Lesperance, G.O.

    1990-01-01

    This paper reports on a number of potential barriers to geothermal development in Hawaii which have been overcome but some remain. Efforts continue to address issues relating to transmission, project economics, the regulatory process, resource verification, and public acceptance

  12. Improved Garvey-Kelson Relations

    International Nuclear Information System (INIS)

    Collis, W. J. F.; Vinko, J. D.; Tripodi, P.

    2009-01-01

    In this paper we develop improved methods of estimating atomic weights and ground state binding energies, similar to the local relations of Garvey-Kelson formulae. We show (Fig. 1) that both the longitudinal (GKL) and transverse(GKT) Garvey-Kelson relations[2] can be derived mathematically from a simpler relationship between 4 nuclides (C1). This base can be used in turn to construct more accurate relations to predict the properties of nuclei far from stability. Historically, the Garvey Kelson local relations appear to be one of the most accurate estimators of atomic mass. However their utility is limited by progressive loss of accuracy in the prediction of nuclei far from stability where it may also be impossible to find the appropriate neighbours. The scheme presented in this paper requires the known masses of only 3 neighbours and is more accurate.(author)

  13. Teorie relativity a relativita teorie

    Czech Academy of Sciences Publication Activity Database

    Havlík, Vladimír

    2005-01-01

    Roč. 53, č. 6 (2005), s. 878-893 ISSN 0015-1831 Institutional research plan: CEZ:AV0Z90090514 Keywords : theory of relativity * relativism * philosophy of science Subject RIV: AA - Philosophy ; Religion

  14. Public Relations & Media Relations (Kritik Budaya Amplop Pada Media Relations Institusi Pendidikan Di Yogyakarta

    Directory of Open Access Journals (Sweden)

    Adhianty Nurjanah

    2015-07-01

    Full Text Available This research is aims to determine how the media relations activities that have been done 10 Public Relations Higher Education, including the possibility of granting cultural envelope in media relations activities during this do. The object of this study is ten (10 Universities in Yogyakarta that consists of three (3 State University (PTN and seven (7 Colleges (PTS. Variations and types of media relations activities have been conducted by 10 universities. The reason is because the electoral college to ten (10 college is a big college in the city of Yogyakarta who own Public Relations and media relations activities that have a systematic and well-planned. In the course of media relations, Public Relations universities do culture accepting envelopes to reporters on the grounds reimburse the costs of transport and not as a "bribe" so that they publicized the news and as a means of imaging the institution. Publicist colleges feel that culture provides envelopes to reporters did not violate the code of ethics of their profession as a Public Relations, On the other hand for journalists, cultural granting envelope can interfere with the independence and constitute a violation of the code of ethics of their profession as journalists. Yet there are also journalists who will receive an envelope in their reporting activities. The discrepancies in the implementation of the code of ethics of journalism, is strongly influenced by the integrity of journalists and policies that apply to each media institution. Penelitian ini bertujuan untuk mengetahui bagaimana kegiatan media relations yang telah dilakukan 10 Public Relations / Humas Perguruan Tinggi tersebut, termasuk kemungkinan adanya budaya pemberian amplop dalam kegiatan media relations yang selama ini dilakukan. Objek penelitian ini adalah sepuluh (10 Perguruan Tinggi di Yogyakarta yang terdiri dari tiga (3 Perguruan Tinggi Negeri (PTN dan tujuh (7 Perguruan Tinggi Swasta (PTS . Beragam variasi dan jenis

  15. 2-year patient-related versus stent-related outcomes

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Christiansen, Evald Høj

    2012-01-01

    years were further assessed with specific focus on patient-related composite (all death, all MI, or any revascularization) and stent-related composite outcomes (cardiac death, target vessel MI, or symptom-driven target lesion revascularization). A total of 1,390 patients were assigned to receive the EES......, and 1,384 patients were assigned to receive the SES. RESULTS: At 2 years, the composite primary endpoint occurred in 8.3% in the EES group and in 8.7% in the SES group (hazard ratio [HR]: 0.94, 95% confidence interval [CI]: 0.73 to 1.22). The patient-related outcome: 15.0% in the EES group versus 15.......80). CONCLUSIONS: At 2-year follow-up, the EES was found to be noninferior to the SES with regard to both patient-related and stent-related clinical outcomes. (Scandinavian Organization for Randomized Trials With Clinical Outcome IV [SORT OUT IV]; NCT00552877)....

  16. Bayesian analogy with relational transformations.

    Science.gov (United States)

    Lu, Hongjing; Chen, Dawn; Holyoak, Keith J

    2012-07-01

    How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy problems. We introduce Bayesian analogy with relational transformations (BART) and apply the model to the task of learning first-order comparative relations (e.g., larger, smaller, fiercer, meeker) from a set of animal pairs. Inputs are coded by vectors of continuous-valued features, based either on human magnitude ratings, normed feature ratings (De Deyne et al., 2008), or outputs of the topics model (Griffiths, Steyvers, & Tenenbaum, 2007). Bootstrapping from empirical priors, the model is able to induce first-order relations represented as probabilistic weight distributions, even when given positive examples only. These learned representations allow classification of novel instantiations of the relations and yield a symbolic distance effect of the sort obtained with both humans and other primates. BART then transforms its learned weight distributions by importance-guided mapping, thereby placing distinct dimensions into correspondence. These transformed representations allow BART to reliably solve 4-term analogies (e.g., larger:smaller::fiercer:meeker), a type of reasoning that is arguably specific to humans. Our results provide a proof-of-concept that structured analogies can be solved with representations induced from unstructured feature vectors by mechanisms that operate in a largely bottom-up fashion. We discuss potential implications for algorithmic and neural models of relational thinking, as well as for the evolution of abstract thought. Copyright 2012 APA, all rights reserved.

  17. Target oriented relational model finding

    OpenAIRE

    Cunha, Alcino; Macedo, Nuno Filipe Moreira; Guimarães, Tiago Miguel Moreira

    2014-01-01

    Lecture Notes in Computer Science 8411, 2014 Model finders are becoming useful in many software engineering problems. Kodkod is one of the most popular, due to its support for relational logic (a combination of first order logic with relational algebra operators and transitive closure), allowing a simpler specification of constraints, and support for partial instances, allowing the specification of a priori (exact, but potentially partial) knowledge about a problem's solution. However, in ...

  18. General relativity 50 years old

    CERN Multimedia

    1966-01-01

    In May 1916, 'The Foundations of General Relativity Theory' by Albert Einstein was published in 'Annalen der Physik'. Fifty years later, this major contribution to scientific thought still has a rather isolated position with respect to the main-stream of scientific theory. (In contrast, the Special Theory of Relativity is one of the cornerstones of sub-nuclear physics.) To mark the anniversary of the publication of Einstein's paper a theoretician from CERN discusses the theory and its present status.

  19. Integrodifferential relations in linear elasticity

    CERN Document Server

    Kostin, Georgy V

    2012-01-01

    This work treats the elasticity of deformed bodies, including the resulting interior stresses and displacements.It also takes into account that some of constitutive relations can be considered in a weak form. To discuss this problem properly, the method of integrodifferential relations is used, and an advanced numerical technique for stress-strain analysis is presented and evaluated using various discretization techniques. The methods presented in this book are of importance for almost all elasticity problems in materials science and mechanical engineering.

  20. Cosmic frontiers of general relativity

    International Nuclear Information System (INIS)

    Kaufmann, W.J. III.

    1977-01-01

    All relevant topics in general astronomy are covered including orientation in space--time, special relativity, gravitation and general relativity, stars and stellar evolution, white dwarfs, pulsars, neutron stars, the black hole, the geometry of the Schwarzschild solution, and electrically charged and rotating black holes. Also the geometry of the Kerr solution, observations of black holes, white holes and particle creation, gravitational waves and lenses, exploding galaxies and massive and primordial black holes are discussed

  1. Does the relativity principle violate?

    International Nuclear Information System (INIS)

    Barashenkov, V.S.

    1994-01-01

    Theoretical and experimental data about a possible existence in Nature of some preferred reference frame with a violation of the principle of relativity are considered. The Einstein's and Lorentz's points of view are compared. Although some experiments are known which, in opinion of their authors, indicate the relativity principle violation persuasive evidences supporting this conclusion are absent for the present. The proposals of new experiments in this region, particularly with electron spin precession, are discussed. 55 refs., 4 figs

  2. Is special relativity logically inconsistent

    International Nuclear Information System (INIS)

    Prokhovnik, S.J.

    1980-01-01

    The author gives his view that Special Relativity is logically and mathematically consistent, as well as physically comprehensible if, and only if, it is firmly based on the single assumption of a unique fundamental reference frame for light propagation. The theory and all its results are derivable from this assumption; the Relativity and Light Principles become intelligible consequences of this assumption; the physical significance and source of time dilation and length contraction are made manifest thereby. (Auth.)

  3. Uncertainty Relations and Possible Experience

    Directory of Open Access Journals (Sweden)

    Gregg Jaeger

    2016-06-01

    Full Text Available The uncertainty principle can be understood as a condition of joint indeterminacy of classes of properties in quantum theory. The mathematical expressions most closely associated with this principle have been the uncertainty relations, various inequalities exemplified by the well known expression regarding position and momentum introduced by Heisenberg. Here, recent work involving a new sort of “logical” indeterminacy principle and associated relations introduced by Pitowsky, expressable directly in terms of probabilities of outcomes of measurements of sharp quantum observables, is reviewed and its quantum nature is discussed. These novel relations are derivable from Boolean “conditions of possible experience” of the quantum realm and have been considered both as fundamentally logical and as fundamentally geometrical. This work focuses on the relationship of indeterminacy to the propositions regarding the values of discrete, sharp observables of quantum systems. Here, reasons for favoring each of these two positions are considered. Finally, with an eye toward future research related to indeterminacy relations, further novel approaches grounded in category theory and intended to capture and reconceptualize the complementarity characteristics of quantum propositions are discussed in relation to the former.

  4. Foundations of relational particle dynamics

    International Nuclear Information System (INIS)

    Anderson, Edward

    2008-01-01

    Relational particle dynamics include the dynamics of pure shape and cases in which absolute scale or absolute rotation are additionally meaningful. These are interesting as regards the absolute versus relative motion debate as well as the discussion of conceptual issues connected with the problem of time in quantum gravity. In spatial dimensions 1 and 2, the relative configuration spaces of shapes are n-spheres and complex projective spaces, from which knowledge I construct natural mechanics on these spaces. I also show that these coincide with Barbour's indirectly constructed relational dynamics by performing a full reduction on the latter. Then the identification of the configuration spaces as n-spheres and complex projective spaces, for which spaces much mathematics is available, significantly advances the understanding of Barbour's relational theory in spatial dimensions 1 and 2. I also provide the parallel study of a new theory for which the position and scale are purely relative but the orientation is absolute. The configuration space for this is an n-sphere regardless of the spatial dimension, which renders this theory a more tractable arena for investigation of implications of scale invariance than Barbour's theory itself

  5. Strategi Public Relations Pariwisata Bali

    Directory of Open Access Journals (Sweden)

    Kadek Dwi Cahaya Putra

    2013-12-01

    Full Text Available Abstract: Bali has to maintain its image and reputation as the world leading class tourist destination. Tourism in fact is a vulnerable industry easily ruined by related issues and crises. Therefore, Public Relations (PR with its communication strategy is highly required to maintain good relationships with related parties. This study is aimed at identifying Bali’s Public Relations positioning and setting up its PR strategies. Data and information are gained by means of questionnaire distributed to The Bali Tourism Board (BTB with its stakeholders as an organization playing important role in Bali tourism. The data is then analyzed by SWOT (Strength Weaknesses Opportunities and Threats analysis. It is then found that Bali’s PR positioning is on quadrant V means Stabilization/Growth. The appropriate strategies then are socializing the importance of Issue and Crisis Management, be more creative in tourism related special events, developing relationships with medias, improving tourism publication’s quality, maintaining relationships with related tourism organization and Bali community internally.

  6. Advanced mechanics and general relativity an introduction to general relativity

    CERN Document Server

    Franklin, Joel

    2010-01-01

    Aimed at advanced undergraduates with background knowledge of classical mechanics and electricity and magnetism, this textbook presents both the particle dynamics relevant to general relativity, and the field dynamics necessary to understand the theory. Focusing on action extremization, the book develops the structure and predictions of general relativity by analogy with familiar physical systems. Topics ranging from classical field theory to minimal surfaces and relativistic strings are covered in a homogeneous manner. Nearly 150 exercises and numerous examples throughout the textbook enable students to test their understanding of the material covered.

  7. MOTHER – CHILD RELATION AND FACTORS AFFECTING THIS RELATION

    OpenAIRE

    TEZEL ŞAHİN, Fatma

    2014-01-01

    The social institution where a child first meet with his birth and sets his social relations is his family. The communication of parents and other members of family determines the place of child in the family. In the preschool period when the basis of future lives is formed, healthy relations made with child are of great importance. What kind of a person the child starting to perceive himself and his environment in this period will be is determined with the life in this period. Family and rel...

  8. MOTHER – CHILD RELATION AND FACTORS AFFECTING THIS RELATION

    OpenAIRE

    TEZEL ŞAHİN, Fatma

    2015-01-01

    The social institution where a child first meet with his birth and sets his social relations is his family. The communication of parents and other members of family determines the place of child in the family. In the preschool period when the basis of future lives is formed, healthy relations made with child are of great importance. What kind of a person the child starting to perceive himself and his environment in this period will be is determined with the life in this period. Family and rel...

  9. Talking about Relations : Factors Influencing the Production of Relational Descriptions

    NARCIS (Netherlands)

    Baltaretu, Adriana-Alexandra; Krahmer, Emiel; van Wijk, Carel; Maes, Alfons

    2016-01-01

    In a production experiment (Experiment 1) and an acceptability rating one (Experiment 2), we assessed two factors, spatial position and salience, which may influence the production of relational descriptions (such as “the ball between the man and the drawer”). In Experiment 1, speakers were asked to

  10. Researcher/Researched: Relations of Vulnerability/Relations of Power

    Science.gov (United States)

    Huckaby, M. Francyne

    2011-01-01

    Turning to reflexive journals and fieldnotes, the author reconsiders Foucault's "relations of power" through her experiences with five research participants, who are professors of education. The paper explores: (1) the translation of Foucault for an analysis of power; (2) the dynamics of researching up and analyzing from below; and (3) the…

  11. Nonlinear generalization of special relativity

    International Nuclear Information System (INIS)

    Winterberg, F.

    1985-01-01

    In Poincares axiomatic formulation special relativity is a derived consequence of a true Lorentz contraction, for a rod in absolute motion through a substratum. Furthermore, Lorentz had shown that the rod contraction can be understood by an inverse square law interaction and therefore special relativity derived from more fundamental principles. The derivation by Lorentz shows that the root of the divergence problems is the singular inverse square law. By replacing the inverse square law with a regular one through the introduction of a finite length, the author has succeeded in deriving a nonlinear generalization of special relativity which eliminates all infinities. Besides the relative velocities, these nonlinear transformation equations also contain absolute velocities against a substratum, but in the limit of small energies they go over into the linear Lorentz transformations. Depending on the smallness of the fundamental length, departures from special relativity can be observed only at very high energies. The theorem that the velocity of light is the same in all reference systems still holds and likewise the conservation laws for energy and momentum

  12. Global income related health inequalities

    Directory of Open Access Journals (Sweden)

    Jalil Safaei

    2007-01-01

    Full Text Available Income related health inequalities have been estimated for various groups of individuals at local, state, or national levels. Almost all of theses estimates are based on individual data from sample surveys. Lack of consistent individual data worldwide has prevented estimates of international income related health inequalities. This paper uses the (population weighted aggregate data available from many countries around the world to estimate worldwide income related health inequalities. Since the intra-country inequalities are subdued by the aggregate nature of the data, the estimates would be those of the inter-country or international health inequalities. As well, the study estimates the contribution of major socioeconomic variables to the overall health inequalities. The findings of the study strongly support the existence of worldwide income related health inequalities that favor the higher income countries. Decompositions of health inequalities identify inequalities in both the level and distribution of income as the main source of health inequality along with inequalities in education and degree of urbanization as other contributing determinants. Since income related health inequalities are preventable, policies to reduce the income gaps between the poor and rich nations could greatly improve the health of hundreds of millions of people and promote global justice. Keywords: global, income, health inequality, socioeconomic determinants of health

  13. Two multi-dimensional uncertainty relations

    International Nuclear Information System (INIS)

    Skala, L; Kapsa, V

    2008-01-01

    Two multi-dimensional uncertainty relations, one related to the probability density and the other one related to the probability density current, are derived and discussed. Both relations are stronger than the usual uncertainty relations for the coordinates and momentum

  14. Recursion Relations for Conformal Blocks

    CERN Document Server

    Penedones, João; Yamazaki, Masahito

    2016-09-12

    In the context of conformal field theories in general space-time dimension, we find all the possible singularities of the conformal blocks as functions of the scaling dimension $\\Delta$ of the exchanged operator. In particular, we argue, using representation theory of parabolic Verma modules, that in odd spacetime dimension the singularities are only simple poles. We discuss how to use this information to write recursion relations that determine the conformal blocks. We first recover the recursion relation introduced in 1307.6856 for conformal blocks of external scalar operators. We then generalize this recursion relation for the conformal blocks associated to the four point function of three scalar and one vector operator. Finally we specialize to the case in which the vector operator is a conserved current.

  15. Relational Leading and Dialogic Process

    DEFF Research Database (Denmark)

    Hansen, Lone Hersted

    The Ph.D. thesis contributes to a relational orientation to leading, emphasizing leadership as a shared, collaborative and co-creative activity. In this paradigm major emphasis is put on dialogue and interaction. Inspired by social constructionist ideas, the thesis considers approaches to learning...... and knowledge building as related to relational leading. The practices developed in the thesis research demonstrate that it is possible to create organizational learning and development through collaborative, dialogic practices in groups and teams, for instance combined with the use of roleplaying. In the work...... with the thesis, dialogically based practices inspired by action research with the aim to enhance collaborative knowledge building, reflexivity and dialogical skills in groups and teams were carried out, analyzed and documented. Participants included school principals, leaders of kindergartens, teachers...

  16. The genesis of general relativity

    CERN Document Server

    Norton, John; Renn, Jürgen; Sauer, Tilman; Stachel, John

    2007-01-01

    This four-volume work represents the most comprehensive documentation and study of the creation of general relativity; one of the fundamental physical theories of the 20th century. It comprises key sources from Einstein and others who from the late 19th to the early 20th century contributed to this monumental development. Some of these sources are presented here in translation for the first time. Einstein’s famous Zurich notebook, which documents the pivotal steps toward general relativity, is reproduced here for the first time and transcribed in its entirety. The volumes offer detailed commentaries and analyses of these sources that are based on a close reading of these documents supplemented by interpretations by the leading historians of relativity. All in all, the facets of this work, based on more than a decade of research, combine to constitute one of the most in-depth studies of a scientific revolution ever written.

  17. Fluctuation relations for anomalous dynamics

    International Nuclear Information System (INIS)

    Chechkin, A V; Klages, R

    2009-01-01

    We consider work fluctuation relations (FRs) for generic types of dynamics generating anomalous diffusion: Lévy flights, long-correlated Gaussian processes and time-fractional kinetics. By combining Langevin and kinetic approaches we calculate the probability distributions of mechanical and thermodynamical work in two paradigmatic nonequilibrium situations, respectively: a particle subject to a constant force and a particle in a harmonic potential dragged by a constant force. We check the transient FR for two models exhibiting superdiffusion, where a fluctuation-dissipation relation does not exist, and for two other models displaying subdiffusion, where there is a fluctuation-dissipation relation. In the two former cases the conventional transient FR is not recovered, whereas in the latter two it holds either exactly or in the long-time limit. (letter)

  18. Umayyad Relations with Byzantium Empire

    Directory of Open Access Journals (Sweden)

    Mansoor Haidari

    2017-06-01

    Full Text Available This research investigates the political and military relations between Umayyad caliphates with the Byzantine Empire. The aim of this research is to clarify Umayyad caliphate’s relations with the Byzantine Empire. We know that these relations were mostly about war and fight. Because there were always intense conflicts between Muslims and the Byzantine Empire, they had to have an active continuous diplomacy to call truce and settle the disputes. Thus, based on the general policy of the Umayyad caliphs, Christians were severely ignored and segregated within Islamic territories. This segregation of the Christians was highly affected by political relationships. It is worthy of mentioning that Umayyad caliphs brought the governing style of the Sassanid kings and Roman Caesar into the Islamic Caliphate system but they didn’t establish civil institutions and administrative organizations.

  19. Pseudo-complex general relativity

    CERN Document Server

    Hess, Peter O; Greiner, Walter

    2016-01-01

    This volume presents an pseudo-complex extension of General Relativity which addresses these issues and presents proposals for experimental examinations in strong fields near a large mass. General Relativity is a beautiful and well tested theory of gravitation. Nevertheless, it implies conceptual problems like the creation of singularities (Black Holes) as a result of the collapse of large masses, or the appearance of event horizons which exclude parts of the space-time from the observation of external observers. The mathematical and geometrical foundations of this extension are displayed in detail, and applications including orbits and accretion disks around large central masses, neutron stars or cosmological models are introduced. Calculations both for classical and extended applications are often executed in the form of problems with extensive solutions, which makes this volume also a valuable resource for any student of General Relativity.

  20. Raymond Aron and International Relations

    DEFF Research Database (Denmark)

    At a time when the field of International Relations (IR) is diverting from grand theoretical debates, rediscovering the value of classical realism and exploring its own intellectual history, this book contributes to these debates by presenting a cohesive view of Raymond Aron’s theory of IR...... multidisciplinarity is possible (and desirable) in the study of IR. This edited collection offers a synthetic approach to Raymond Aron’s theory of International Relations by bringing together some of the most prominent specialists on Raymond Aron, thus filling an important gap in the current market of books devoted...... to IR theories and the historiography of the field. The volume is divided into three parts: the first part explores Aron’s intellectual contribution to the theoretical debates in IR, thus showing his originality and prescience; the second part traces Aron’s influence and explores his relations...

  1. Unifying relations for scattering amplitudes

    Science.gov (United States)

    Cheung, Clifford; Shen, Chia-Hsien; Wen, Congkao

    2018-02-01

    We derive new amplitudes relations revealing a hidden unity among a wideranging variety of theories in arbitrary spacetime dimensions. Our results rely on a set of Lorentz invariant differential operators which transmute physical tree-level scattering amplitudes into new ones. By transmuting the amplitudes of gravity coupled to a dilaton and two-form, we generate all the amplitudes of Einstein-Yang-Mills theory, Dirac-Born-Infield theory, special Galileon, nonlinear sigma model, and biadjoint scalar theory. Transmutation also relates amplitudes in string theory and its variants. As a corollary, celebrated aspects of gluon and graviton scattering like color-kinematics duality, the KLT relations, and the CHY construction are inherited traits of the transmuted amplitudes. Transmutation recasts the Adler zero as a trivial consequence of the Weinberg soft theorem and implies new subleading soft theorems for certain scalar theories.

  2. Relational uncertainty in service dyads

    DEFF Research Database (Denmark)

    Kreye, Melanie

    2017-01-01

    in service dyads and how they resolve it through suitable organisational responses to increase the level of service quality. Design/methodology/approach: We apply the overall logic of Organisational Information-Processing Theory (OIPT) and present empirical insights from two industrial case studies collected...... the relational uncertainty increased the functional quality while resolving the partner’s organisational uncertainty increased the technical quality of the delivered service. Originality: We make two contributions. First, we introduce relational uncertainty to the OM literature as the inability to predict...... and explain the actions of a partnering organisation due to a lack of knowledge about their abilities and intentions. Second, we present suitable organisational responses to relational uncertainty and their effect on service quality....

  3. The power of general relativity

    International Nuclear Information System (INIS)

    Clifton, Timothy; Barrow, John D.

    2005-01-01

    We study the cosmological and weak-field properties of theories of gravity derived by extending general relativity by means of a Lagrangian proportional to R 1+δ . This scale-free extension reduces to general relativity when δ→0. In order to constrain generalizations of general relativity of this power class, we analyze the behavior of the perfect-fluid Friedmann universes and isolate the physically relevant models of zero curvature. A stable matter-dominated period of evolution requires δ>0 or δ -19 assuming that Mercury follows a timelike geodesic. The combination of these observational constraints leads to the overall bound 0≤δ -19 on theories of this type

  4. Special relativity a heuristic approach

    CERN Document Server

    Hassani, Sadri

    2017-01-01

    Special Relativity: A Heuristic Approach provides a qualitative exposition of relativity theory on the basis of the constancy of the speed of light. Using Einstein's signal velocity as the defining idea for the notion of simultaneity and the fact that the speed of light is independent of the motion of its source, chapters delve into a qualitative exposition of the relativity of time and length, discuss the time dilation formula using the standard light clock, explore the Minkowski four-dimensional space-time distance based on how the time dilation formula is derived, and define the components of the two-dimensional space-time velocity, amongst other topics. Provides a heuristic derivation of the Minkowski distance formula Uses relativistic photography to see Lorentz transformation and vector algebra manipulation in action Includes worked examples to elucidate and complement the topic being discussed Written in a very accessible style

  5. Ciemat Relational Capital: Institutional Presence

    International Nuclear Information System (INIS)

    Vaquero Ortiz, E. M.; González Pineda, L. M.; Cascante Díaz, E.

    2015-01-01

    The resources in any organization for its activity development can be divided into two main groups: tangible assets and intangible assets. In recent decades there has been a recognition of the importance of the intangible assets as value generators for the development and growth of organizations. And the so called Relational Capital is among them Relational Capital arises from the relationship processes that an organization maintains with external agents. Thus, in the case of a public research institution, such as CIEMAT, it includes the relations with projects financing organizations, with partners and with customers (both public and private entities which are serviced), as well as the institutional presence understood as the participation in discussion and coordination forums (foundations, associations, committees…). This report presents a study of CIEMAT institutional presence in the year 2015.

  6. Relative Permeability of Fractured Rock

    Energy Technology Data Exchange (ETDEWEB)

    Mark D. Habana

    2002-06-30

    Contemporary understanding of multiphase flow through fractures is limited. Different studies using synthetic fractures and various fluids have yielded different relative permeability-saturation relations. This study aimed to extend the understanding of multiphase flow by conducting nitrogen-water relative permeability experiments on a naturally-fractured rock from The Geysers geothermal field. The steady-state approach was used. However, steady state was achieved only at the endpoint saturations. Several difficulties were encountered that are attributed to phase interference and changes in fracture aperture and surface roughness, along with fracture propagation/initiation. Absolute permeabilities were determined using nitrogen and water. The permeability values obtained change with the number of load cycles. Determining the absolute permeability of a core is especially important in a fractured rock. The rock may change as asperities are destroyed and fractures propagate or st rain harden as the net stresses vary. Pressure spikes occurred in water a solute permeability experiments. Conceptual models of an elastic fracture network can explain the pressure spike behavior. At the endpoint saturations the water relative permeabilities obtained are much less than the nitrogen gas relative permeabilities. Saturations were determined by weighing and by resistivity calculations. The resistivity-saturation relationship developed for the core gave saturation values that differ by 5% from the value determined by weighing. Further work is required to complete the relative permeability curve. The steady-state experimental approach encountered difficulties due to phase interference and fracture change. Steady state may not be reached until an impractical length of time. Thus, unsteady-state methods should be pursued. In unsteady-state experiments the challenge will be in quantifying rock fracture change in addition to fluid flow changes.

  7. Coping, social relations, and communication

    DEFF Research Database (Denmark)

    Thastum, Mikael; Jensen-Johansen, Mikael Birkelund; Gubba, Lotte

    2008-01-01

    and concerns for the child. Twenty-one children from 15 families and their parents were interviewed. In 13 families the mother was ill, in two the father. Children were aware of the facts of the illness, but there was limited emotional communication between the generations. The children were very observant...... examples of parentification were found. Communication patterns and parental coping seemed to be highly related to the child's coping repertoire. Even though most children seemed to manage rather well, all children were strongly affected by the illness. The `healthiest' adaptation related to factors within...

  8. The geometry of special relativity

    International Nuclear Information System (INIS)

    Parizet, Jean

    2008-01-01

    This book for students in mathematics or physics shows the interest of geometry to understand special relativity as a consequence of invariance of Maxwell equations and of constancy of the speed of light. Space-time is actually provided with a geometrical structure and a physical interpretation: at each observer are associated his own time and his own physical space in which occur events he is concerned with. This leads to a natural approach to special relativity. The Lorentz group and its algebra are then studied by using matrices and the Pauli algebra. Quaternions are also addressed

  9. Environmental communication in business relations

    DEFF Research Database (Denmark)

    Holgaard, Jette Egelund

    in the way, in which a company organise, communicate and learn in order to succeed in business. The ambition level regarding environmental improvements in each strategy can differ. The three strategies are not mutually exclusive; on the contrary, they supplement and support each other. Empirical data...... is collected by means of environmental reports, qualitative questionnaires, and a case study at Grundfos A/S in Denmark. These data will be discussed in relation to the three strategies of environmental communication. Different trends in environmental communication practise are found, and on this basis......, recommendations are made in order to improve environmental communication in business relations....

  10. The special theory of relativity

    CERN Document Server

    Devanathan, V

    2015-01-01

    THE SPECIAL THEORY OF RELATIVITY, designed as a text book for undergraduate and postgraduate students, deals with the Michelson-Morley experiment, the concept of unified space and time, the Lorentz transformation of physical quantities, length contraction, time dilation, the Minkowski space, the mass-energy relation, the concept of four-vectors, the relativistic mechanics, the laws of transformation between centre of momentum and laboratory systems, the relativistic kinematics, the unification of laws of electricity and magnetism into laws of electromagnetism, the invariance of Maxwell's equations under Lorentz transformation and the Lorentz transformation of electromagnetic quantities. KEY FEATURES: * Review Questions * Problems * Solutions to Problems * Multiple Choice Questions

  11. Persondata i relation til ting

    DEFF Research Database (Denmark)

    Blume, Peter

    2011-01-01

    En intelligent verden er under udvikling. En verden, hvor stadig flere ting har indbygget digital teknologi, der indsamler personoplysninger med henblik på at lette borgernes tilværelseog for at realisere samfundsmæssige målsætninger. Atiklen vedrører især anvendelsen af intelligente ting i relat...... relation til måling af energiforbrug m.v. Dette kan medføre en øget anvendelse af persondata, og på denne baggrund sætter artiklen fokus på, hvorledes persondataretten finder anvendelse i denne sammenhæng....

  12. Radioimmunoassay and other related techniques

    International Nuclear Information System (INIS)

    Zarkawi, Moutaz

    1993-04-01

    The article reviews principles, requirements and reliability criteria of radioimmunoassay (RIA). Since basic reactions involved in RIA and related techniques are derived from reactions which take place in the immune system (IS) of humans and animals, the IS and the way it works will be described. In addition to RIA which involves the use of isotopes as tracers (labels), other non-radioisotopic and recent immunoassay techniques i.e. enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay (CLIA) and fluoroimmunoassay (FIA) will be dealt with. Some important and related terms will be defined and explained. (author). 59 refs., 4 figs

  13. Gravitation. [Book on general relativity

    Science.gov (United States)

    Misner, C. W.; Thorne, K. S.; Wheeler, J. A.

    1973-01-01

    This textbook on gravitation physics (Einstein's general relativity or geometrodynamics) is designed for a rigorous full-year course at the graduate level. The material is presented in two parallel tracks in an attempt to divide key physical ideas from more complex enrichment material to be selected at the discretion of the reader or teacher. The full book is intended to provide competence relative to the laws of physics in flat space-time, Einstein's geometric framework for physics, applications with pulsars and neutron stars, cosmology, the Schwarzschild geometry and gravitational collapse, gravitational waves, experimental tests of Einstein's theory, and mathematical concepts of differential geometry.

  14. Conformal covariance of general relativity

    International Nuclear Information System (INIS)

    Ionescu-Pallas, N.; Gottlieb, I.

    1980-01-01

    The Einstein's equations of General Relativity are written in a conformal metric, resulting as a consequence of geometrizing the pressure forces. Accordingly, the trajectory of a test body pursues a geodetic line even inside the source of gravitational field. Moreover, the pressure, entering the perfect fluid scheme, may be replaced by a certain scalar interaction. This new manner of interpreting General Relativity is then applied to Cosmology, in order to build up a model of Universe whose static limit should coincide with that of Einstein. At the same time, the cosmological constant is connected to the scalar interaction acquiring a plausible explanation. (author)

  15. Functional statistics and related fields

    CERN Document Server

    Bongiorno, Enea; Cao, Ricardo; Vieu, Philippe

    2017-01-01

    This volume collects latest methodological and applied contributions on functional, high-dimensional and other complex data, related statistical models and tools as well as on operator-based statistics. It contains selected and refereed contributions presented at the Fourth International Workshop on Functional and Operatorial Statistics (IWFOS 2017) held in A Coruña, Spain, from 15 to 17 June 2017. The series of IWFOS workshops was initiated by the Working Group on Functional and Operatorial Statistics at the University of Toulouse in 2008. Since then, many of the major advances in functional statistics and related fields have been periodically presented and discussed at the IWFOS workshops. .

  16. Hermitian relativity, chromodynamics and confinement

    International Nuclear Information System (INIS)

    Treder, H.J.

    1983-01-01

    The extension of the Riemann metrics of General Relativity to the complex domain (substitution of the symmetry conditions for the fundamental tensor, the affinity and the Ricci curvature by the conditions of hermicity) leads to a 'Generalized Theory of Gravity' (Einstein) describing the Newton-Einstein gravodynamics combined with the chromodynamics of quarks. The interaction of gravodynamics and chromodynamics implied by the Einstein-Schroedinger field equations of the hermitian relativity theory enforces the 'confinement'. The 'confinement' prevents the gravitational potential from divergence which would result in the lack of a Riemann space-time metric

  17. Relative ultrasound energy measurement circuit

    OpenAIRE

    Gustafsson, E.Martin I.; Johansson, Jonny; Delsing, Jerker

    2005-01-01

    A relative ultrasound energy estimation circuit has been designed in a standard 0.35-μm CMOS process, to be a part of a thumb size internet connected wireless ultrasound measurement system. This circuit measures the relative energy between received ultrasound pulses, and presents an output signal that is linear to the received energy. Post-layout simulations indicate 7 bit linearity for 500 mV input signals, 5 μsec startup and stop times, 2.6 mW power consumption during active state. The acti...

  18. The biomedical discourse relation bank

    Directory of Open Access Journals (Sweden)

    Joshi Aravind

    2011-05-01

    Full Text Available Abstract Background Identification of discourse relations, such as causal and contrastive relations, between situations mentioned in text is an important task for biomedical text-mining. A biomedical text corpus annotated with discourse relations would be very useful for developing and evaluating methods for biomedical discourse processing. However, little effort has been made to develop such an annotated resource. Results We have developed the Biomedical Discourse Relation Bank (BioDRB, in which we have annotated explicit and implicit discourse relations in 24 open-access full-text biomedical articles from the GENIA corpus. Guidelines for the annotation were adapted from the Penn Discourse TreeBank (PDTB, which has discourse relations annotated over open-domain news articles. We introduced new conventions and modifications to the sense classification. We report reliable inter-annotator agreement of over 80% for all sub-tasks. Experiments for identifying the sense of explicit discourse connectives show the connective itself as a highly reliable indicator for coarse sense classification (accuracy 90.9% and F1 score 0.89. These results are comparable to results obtained with the same classifier on the PDTB data. With more refined sense classification, there is degradation in performance (accuracy 69.2% and F1 score 0.28, mainly due to sparsity in the data. The size of the corpus was found to be sufficient for identifying the sense of explicit connectives, with classifier performance stabilizing at about 1900 training instances. Finally, the classifier performs poorly when trained on PDTB and tested on BioDRB (accuracy 54.5% and F1 score 0.57. Conclusion Our work shows that discourse relations can be reliably annotated in biomedical text. Coarse sense disambiguation of explicit connectives can be done with high reliability by using just the connective as a feature, but more refined sense classification requires either richer features or more

  19. Evaluating the Relational Coordination instrument

    DEFF Research Database (Denmark)

    Edwards, Kasper; Lundstrøm, Sanne Lykke

    2014-01-01

    consistency, interrater agreement and reliability, structural validity, content validity. However as relational coordination is being used as a diagnostics tool it is important to examine further if the instrument can measure changes. Indeed we need to know how precise and sensitive the instrument is when....... We distinguish between statistical and clinical significance. Statistical significance is calculated using T-test. Clinical significance is the minimal amount of change in relational coordination score that is not considered noise. Sensitivity of the instrument i.e. the ability of the instrument...

  20. The gauge in general relativity

    International Nuclear Information System (INIS)

    Cohn, J.

    1975-01-01

    The view is taken that the field equations of General Relativity, without a definition of congruence of length and time intervals at different events, are without physical content. The possibility is explored that the customary Einstein field equations are to be used but with a different congruence definition than is customary. When these resulting equations are, in turn, expressed with the customary congruence, they comprise a new set of field equations physically not equivalent to either Einstein's or Brans-Dicke's formulations of general relativity. Similarities with Einstein's and Brans-Dicke's formulations are discussed, and the possibility of experimental confirmation of these new equations is also briefly considered. (author)

  1. New view of relativity theory

    International Nuclear Information System (INIS)

    Martini, Luiz Cesar

    2014-01-01

    This article results from Introducing the Dimensional Continuous Space-Time Theory that was published in reference 1. The Dimensional Continuous Space-Time Theory shows a series of facts relative to matter, energy, space and concludes that empty space is inelastic, absolutely stationary, motionless, perpetual, without possibility of deformation neither can it be destroyed or created. A elementary cell of empty space or a certain amount of empty space can be occupied by any quantity of energy or matter without any alteration or deformation. As a consequence of these properties and being a integral part of the theory, the principles of Relativity Theory must be changed to become simple and intuitive.

  2. Results from Numerical General Relativity

    Science.gov (United States)

    Baker, John G.

    2011-01-01

    For several years numerical simulations have been revealing the details of general relativity's predictions for the dynamical interactions of merging black holes. I will review what has been learned of the rich phenomenology of these mergers and the resulting gravitational wave signatures. These wave forms provide a potentially observable record of the powerful astronomical events, a central target of gravitational wave astronomy. Asymmetric radiation can produce a thrust on the system which may accelerate the single black hole resulting from the merger to high relative velocity.

  3. General relativity and gravitational waves

    CERN Document Server

    Weber, Johanna

    1961-01-01

    An internationally famous physicist and electrical engineer, the author of this text was a pioneer in the investigation of gravitational waves. Joseph Weber's General Relativity and Gravitational Waves offers a classic treatment of the subject. Appropriate for upper-level undergraduates and graduate students, this text remains ever relevant. Brief but thorough in its introduction to the foundations of general relativity, it also examines the elements of Riemannian geometry and tensor calculus applicable to this field.Approximately a quarter of the contents explores theoretical and experimenta

  4. Boxing-related head injuries.

    Science.gov (United States)

    Jayarao, Mayur; Chin, Lawrence S; Cantu, Robert C

    2010-10-01

    Fatalities in boxing are most often due to traumatic brain injury that occurs in the ring. In the past 30 years, significant improvements in ringside and medical equipment, safety, and regulations have resulted in a dramatic reduction in the fatality rate. Nonetheless, the rate of boxing-related head injuries, particularly concussions, remains unknown, due in large part to its variability in clinical presentation. Furthermore, the significance of repeat concussions sustained when boxing is just now being understood. In this article, we identify the clinical manifestations, pathophysiology, and management of boxing-related head injuries, and discuss preventive strategies to reduce head injuries sustained by boxers.

  5. BOOK REVIEW An Introduction to Relativity An Introduction to Relativity

    Science.gov (United States)

    Dray, Tevian

    2011-02-01

    As is clearly stated in the preface, this book is a fresh rewrite of Narlikar's published lecture notes [1] from 1978, resulting in a unique historical perspective with a modernized presentation. For workers in the field, this book provides a fascinating glimpse of the state of the art 30 years ago, but there are some inevitable idiosyncracies which might make it less useful to the beginner, especially those attempting to read this book on their own. The author is well-known for his informal, readable style, and this book is no exception. Although the treatment is overly algebraic from this reviewer's modern perspective, that is not necessarily a drawback, and does accurately reflect contemporary usage. This text is a `math first' approach to relativity, presenting the tensor calculus first, and the physics second. Not surprisingly given the author's interests, there is an emphasis on cosmological applications. After a quick review of special relativity, the book jumps right in with a fairly standard introduction to tensor calculus, followed almost immediately by chapters on Einstein's equations, the Schwarzschild solution, experimental tests, relativistic astrophysics, and black holes, followed in turn by several chapters on cosmology. This new text is a faithful adaptation of the earlier text, with essentially identical tables of contents. In fact, the only notable differences are the opening chapter summarizing special relativity, a brief new chapter on gravitational radiation, and the exclusion of a lecture on the Steady State Theory — and that material appears separately in the author's cosmology text [2]. Some of the material, such as the excellent chapter on symmetries, is largely identical to the original, but most of the material has been extensively rewritten, with most of the changes being to presentation, rather than content. There are some seldom seen gems in this book, such as the aforementioned discussion of symmetries, the extensive discussion of

  6. Job-Related Maternity Benefits.

    Science.gov (United States)

    Citizens Advisory Council on the Status of Women, Washington, DC.

    The Citizens' Advisory Council on the Status of Women in October 1970 adopted a statement of principles that views childbirth and complications of pregnancy, for all job-related purposes, as temporary disabilities that should be treated as such under any health insurance, temporary disability insurance, or sick leave plan of an employer, union, or…

  7. Relational Database Technology: An Overview.

    Science.gov (United States)

    Melander, Nicole

    1987-01-01

    Describes the development of relational database technology as it applies to educational settings. Discusses some of the new tools and models being implemented in an effort to provide educators with technologically advanced ways of answering questions about education programs and data. (TW)

  8. Index Selection in Relational Databases

    NARCIS (Netherlands)

    Choenni, R.S.; Blanken, Henk; Chang, S.C.

    Intending to develop a tool which aims to support the physical design of relational databases can not be done without considering the problem of index selection. Generally the problem is split into a primary and secondary index selection problem and the selection is done per table. Whereas much

  9. School Public Relations Journal, 2001.

    Science.gov (United States)

    Holliday, Albert E., Ed.

    2001-01-01

    This document consists of the four 2001 issues of a journal (formerly "Journal of Educational Relations") published to promote student achievement through positive school-home-community relationships. Articles in the first issue include: "Crossing Basic/Higher Education Boundaries through a School-University Partnership" and "How a Group of Middle…

  10. Green economy and related concepts

    NARCIS (Netherlands)

    Loiseau, Eleonore; Saikku, Laura; Antikainen, Riina; Droste, Nils; Hansjürgens, Bernd; Pitkänen, Kati; Leskinen, Pekka; Kuikman, Peter; Thomsen, Marianne

    2016-01-01

    For the last ten years, the notion of a green economy has become increasingly attractive to policy makers. However, green economy covers a lot of diverse concepts and its links with sustainability are not always clear. In this article, we focus on definitions of green economy and related concepts

  11. [Projective identification in human relations].

    Science.gov (United States)

    Göka, Erol; Yüksel, Fatih Volkan; Göral, F Sevinç

    2006-01-01

    Melanie Klein, one of the pioneers of Object Relations Theory, first defined "projective identification", which is regarded as one of the most efficacious psychoanalytic concepts after the discovery of the "unconscious". Examination of the literature on "projective identification" shows that there are various perspectives and theories suggesting different uses of this concept. Some clinicians argue that projective identification is a primitive defense mechanism observed in severe psychopathologies like psychotic disorder and borderline personality disorder, where the intra-psychic structure has been damaged severely. Others suggest it to be an indispensable part of the transference and counter-transference between the therapist and the patient during psychotherapy and it can be used as a treatment material in the therapy by a skillful therapist. The latter group expands the use of the concept through normal daily relationships by stating that projective identification is one type of communication and part of the main human relation mechanism operating in all close relationships. Therefore, they suggest that projective identification has benign forms experienced in human relations as well as malign forms seen in psychopathologies. Thus, discussions about the definition of the concept appear complex. In order to clarify and overcome the complexity of the concept, Melanie Klein's and other most important subsequent approaches are discussed in this review article. Thereby, the article aims to explain its important function in understanding the psychopathologies, psychotherapeutic relationships and different areas of normal human relations.

  12. General Relativity: horizons for tests

    Science.gov (United States)

    Yatskiv, Ya. S.; Alexandrov, A. N.; Vavilova, I. B.; Zhdanov, V. I.; Zhuk, A. I.; Kudrya, Yu. N.; Parnovsky, S. L.; Fedorova, E. V.; Khmil, S. V.

    2013-12-01

    Theoretical basis of the General Relativity Theory (GRT), its experimental tests as well as GRT applications are briefly summarized taking into account the results of the last decade. The monograph addresses scientists, post-graduated students, and students specialized in the natural sciences as well as everyone who takes an interest in GRT.

  13. General relativity and dark matter

    International Nuclear Information System (INIS)

    Pestov, A.B.

    1993-01-01

    It is shown that from the first principles of General Relativity it follows that there exists a new type of interactions which are tightly connected with the gravitational interactions. New particles representing a new form of interactions do not interact electromagnetically, strongly and weakly with the known elementary particles. Physics of the new particles is defined by the Planck scales. (author.). 9 refs

  14. Tides. Ocean Related Curriculum Activities.

    Science.gov (United States)

    Marrett, Andrea

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  15. Doing relational research through roleplaying

    DEFF Research Database (Denmark)

    Hansen, Lone Hersted

    2018-01-01

    and leaders working in an institution. It is carried out and described from within the movement, often referred to as the dialogical turn (Flecha et al. 2003) or the relational turn (Donati 2011). The practice is rooted in a constructionist stance and inspired by action research and arts-based research. I...

  16. Work-related voice disorder

    Directory of Open Access Journals (Sweden)

    Paulo Eduardo Przysiezny

    2015-04-01

    Full Text Available INTRODUCTION: Dysphonia is the main symptom of the disorders of oral communication. However, voice disorders also present with other symptoms such as difficulty in maintaining the voice (asthenia, vocal fatigue, variation in habitual vocal fundamental frequency, hoarseness, lack of vocal volume and projection, loss of vocal efficiency, and weakness when speaking. There are several proposals for the etiologic classification of dysphonia: functional, organofunctional, organic, and work-related voice disorder (WRVD.OBJECTIVE: To conduct a literature review on WRVD and on the current Brazilian labor legislation.METHODS: This was a review article with bibliographical research conducted on the PubMed and Bireme databases, using the terms "work-related voice disorder", "occupational dysphonia", "dysphonia and labor legislation", and a review of labor and social security relevant laws.CONCLUSION: WRVD is a situation that frequently is listed as a reason for work absenteeism, functional rehabilitation, or for prolonged absence from work. Currently, forensic physicians have no comparative parameters to help with the analysis of vocal disorders. In certain situations WRVD may cause, work disability. This disorder may be labor-related, or be an adjuvant factor to work-related diseases.

  17. EU-Russia Cultural Relations

    Directory of Open Access Journals (Sweden)

    Elena Sidorova

    2014-05-01

    Full Text Available This article analyzes the link between culture and diplomacy between Russia and the European Union, and shows the importance of cultural relations. It examines the common space of science, education and culture introduced at the 2003 EU-Russia Summit in St. Petersburg and the application of the principles of this concept that were established at the 2005 EU-Russia Summit in Moscow. It then considers EU-Russia collaboration on humanitarian action and the challenges that both parties face in this sphere. It also explains the formation of EU domestic and foreign cultural policy, and the role of European institutions and states in cultural affairs and diplomacy, as well as key elements and mechanisms of contemporary Russian foreign cultural policy. In addition, the article focuses on the European side of post-Soviet EU-Russia cultural relations. This cultural collaboration is defined as a competitive neighbourhood. EU and Russian interests collide: while Europeans try to promote their values, norms and standards within the framework of the European Neighbourhood Policy, Russia seeks to culturally influence and engage in this region for geostrategic and historical reasons. Finally, the article assesses the prospects for the EU-Russia cultural relations and emphasizes the role of ideology in improving such relations.

  18. Stroke-Related Translational Research

    Science.gov (United States)

    Caplan, Louis R.; Arenillas, Juan; Cramer, Steven C.; Joutel, Anne; Lo, Eng H.; Meschia, James; Savitz, Sean; Tournier-Lasserve, Elizabeth

    2013-01-01

    Stroke-related translational research is multifaceted. Herein, we highlight genome-wide association studies and genetic studies of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, COL4A1 mutations, and cerebral cavernous malformations; advances in molecular biology and biomarkers; newer brain imaging research; and recovery from stroke emphasizing cell-based and other rehabilitative modalities. PMID:21555605

  19. Verifying the Theory of Relativity

    Science.gov (United States)

    Chandrasekhar, S.

    1975-01-01

    This article, based on a talk the author gave to the 'Innominates', an interdisciplinary faculty group at the University of Chicago, focuses on events of the years surrounding the British Expeditions to Brazil and West Africa in 1919 that led to the confirmation of Einstein's theory of relativity. (BT)

  20. Age-Related Hearing Loss

    Science.gov (United States)

    ... 29, 2017 Granicus - Health Topics Languages Español Download PDF version Order free publications Find organizations Syndicate content Related Topics Do You Need a Hearing Test? Hearing Loss and Older Adults News Spatial organization of cells in the inner ear enables the sense and ...

  1. Internship Practices in Public Relations.

    Science.gov (United States)

    Kendall, Robert

    1980-01-01

    Surveys the range of job experiences available to journalism students and suggests how these internship programs could be standardized. Available from Public Relations Review, Communication Research Associates, Inc., 7338 Baltimore Blvd., Suite 101A, College Park, MD 20740; one year, $15.00; two years $27.00; three years $39.00. (JMF)

  2. Genetics in Relation to Biology.

    Science.gov (United States)

    Stewart, J. Bird

    1987-01-01

    Claims that most instruction dealing with genetics is limited to sex education and personal hygiene. Suggests that the biology curriculum should begin to deal with other issues related to genetics, including genetic normality, prenatal diagnoses, race, and intelligence. Predicts these topics will begin to appear in British examination programs.…

  3. Testing general relativity on accelerators

    Directory of Open Access Journals (Sweden)

    Tigran Kalaydzhyan

    2015-11-01

    Full Text Available Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable – maximal energy of the scattered photons – would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.

  4. Human Relations Class. A Syllabus.

    Science.gov (United States)

    Guillen, Mary A.

    A junior high level human relations class develops human interaction and oral communication skills. A week-by-week syllabus contains the following components: introduction of the students to each other and to the principles of body language, transactional analysis, and group interaction; behavior contracts; group dynamics topics and exercises;…

  5. Glucose effectiveness in nondiabetic relatives

    DEFF Research Database (Denmark)

    Egede, M B; Henriksen, J-E; Durck, T T

    2014-01-01

    AIMS: Reduced glucose effectiveness is a predictor of future glucose tolerance in individuals with a family history of type 2 diabetes. We examined retrospectively at 10 years in normoglycemic relatives of diabetic subjects (RELs) the pathophysiological role of glucose effectiveness in the develo...

  6. Thinking Relationally about Studying "Up"

    Science.gov (United States)

    Stich, Amy E.; Colyar, Julia E.

    2015-01-01

    In this paper, the authors argue that despite a resurgence of elite studies, the majority of existing scholarship works to reify and legitimize social inequality through its language and method. In particular, the authors utilize Pierre Bourdieu's concept of relational thinking to review and critique contemporary research on elite education and…

  7. Hybrid Tourism-Related Structures

    DEFF Research Database (Denmark)

    Pasgaard, Jens Christian

    2014-01-01

    This article is rooted in theories presented in the PhD dissertation Tourism and Strategic Planning (Pasgaard 2012) and features a number of much discussed concepts related to the complicated phenomenon of tourism and to the discipline of strategic urban planning. It is beyond the scope of this a...

  8. Relativity tests and their motivation

    International Nuclear Information System (INIS)

    Lehnert, Ralf

    2011-01-01

    Some motivations for Lorentz-symmetry tests in the context of quantum-gravity phenomenology are reiterated. The description of the emergent low-energy effects with the Standard-Model Extension (SME) is reviewed. The possibility of constraining such effects with dispersion-relation analyses of collider data is established.

  9. General Relativity: Geometry Meets Physics

    Science.gov (United States)

    Thomsen, Dietrick E.

    1975-01-01

    Observing the relationship of general relativity and the geometry of space-time, the author questions whether the rest of physics has geometrical explanations. As a partial answer he discusses current research on subatomic particles employing geometric transformations, and cites the existence of geometrical definitions of physical quantities such…

  10. The Special Theory of Relativity

    Indian Academy of Sciences (India)

    cial theory of relativity were published in the journal. Annalen der Physik, and were titled 'On the electro- dynamics of ... Historical Background. In order to set Einstein's work in proper perspective, re- call that, in ... ideas of absolute space and time firmly entrenched, most physicists thought that this speed was correct only in.

  11. Stigma Management in International Relations

    DEFF Research Database (Denmark)

    Adler-Nissen, Rebecca

    2014-01-01

    This article develops a theoretical approach to stigma in international relations and resituates conventional approaches to the study of norms and international order. Correcting the general understanding that common values and norms are the building blocks of social order, this article claims...

  12. Paediatric horse-related trauma.

    Science.gov (United States)

    Theodore, Jane E; Theodore, Sigrid G; Stockton, Kellie A; Kimble, Roy M

    2017-06-01

    This retrospective cohort study reported on the epidemiology of horse-related injuries for patients presenting to the only tertiary paediatric trauma hospital in Queensland. The secondary outcome was to examine the use of helmets and adult supervision. Traumatic brain injury (TBI) was examined in relation to helmet use. Morbidity and mortality were also recorded. Included were all patients presenting with any horse-related trauma to the Royal Children's Hospital in Brisbane from January 2008 to August 2014. Data were retrospectively collected on patient demographics, hospital length of stay (LOS), mechanism of injury (MOI), safety precautions taken, diagnoses and surgical procedures performed. Included in the analysis were 187 incidents involving 171 patients. Most patients were aged 12-14 years (36.9%) and female (84.5%). The most common MOI were falls while riding horses (97.1%). Mild TBI (24.6%) and upper limb fractures (20.9%) were common injuries sustained. Patients who wore helmets had significantly reduced hospital LOS and severity of TBI when compared with those who did not wear helmets (P horses, in addition to being a compulsory requirement whilst horse riding. Prompts in documentation may assist doctors to record the use of safety attire and adult supervision. This will allow future studies to further investigate these factors in relation to clinical outcomes. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  13. Modified General Relativity and Cosmology

    Science.gov (United States)

    Abdel-Rahman, A.-M. M.

    1997-10-01

    Aspects of the modified general relativity theory of Rastall, Al-Rawaf and Taha are discussed in both the radiation- and matter-dominated flat cosmological models. A nucleosynthesis constraint on the theory's free parameter is obtained and the implication for the age of the Universe is discussed. The consistency of the modified matter- dominated model with the neoclassical cosmological tests is demonstrated.

  14. Public Relations in Special Libraries.

    Science.gov (United States)

    Rutkowski, Hollace Ann; And Others

    1991-01-01

    This theme issue includes 11 articles on public relations (PR) in special libraries. Highlights include PR at the Special Libraries Association (SLA); sources for marketing research for libraries; developing a library image; sample PR releases; brand strategies for libraries; case studies; publicizing a consortium; and a bibliography of pertinent…

  15. Wild Vietnamese relatives of blueberries

    Science.gov (United States)

    rom 25 October to 14 November 2015, wild relatives of cultivated blueberry, Vaccinium corymbosum, were collected during a Vietnamese-US cooperative expedition in Northern Vietnam. The exploration involved representatives of the Plant Resources Center, Vietnam Academy of Agricultural Sciences, in Han...

  16. Industrial relations in agriculture examined

    NARCIS (Netherlands)

    Schaapman, M.H.

    2003-01-01

    Agriculture remains an important part of the Dutch economy, accounting for around 10%of GDP . The sector is currently undergoing major changes in terms of production, markets and technology, with important implications for employment. This article examines industrial relations in agriculture,

  17. Hugging fusion and related topics

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    An important problem related to the synthesis of very heavy nuclides by fusion of two heavy-ions is the extra push effect. To avoid it, we propose a hugging fusion, which is the fusion of two well-deformed heavy-ions. (author)

  18. Towards Online Relational Schema Transformations

    NARCIS (Netherlands)

    Wevers, L.; Hofstra, M; Tammens, M; Huisman, Marieke; van Keulen, Maurice

    2014-01-01

    Current relational database systems are ill-equipped for changing the structure of data while the database is in use. This is a real problem for systems for which we expect 24/7 availability, such as telecommunication, payment, and control systems. As a result, developers tend to avoid making

  19. Surfing-related ocular injuries.

    Science.gov (United States)

    Kim, J W; McDonald, H R; Rubsamen, P E; Luttrull, J K; Drouilhet, J H; Frambach, D A; Boyer, D S; Lambrou, F H; Hendrick, A; Weiss, J N; Engstrom, R E; Ing, M

    1998-01-01

    This report evaluates the clinical characteristics of surfing-related ocular trauma to learn the nature of such injuries and propose possible preventive measures. The authors reviewed 11 cases of surfing-related eye injuries caused by direct trauma from the surfboard, studying their mechanism of injury, the associated ocular complications, and the anatomic and visual outcomes of surgical repair. Surfing-related ocular injuries occurred exclusively in young males (mean age, 24.8 years; range, 14-37 years). The mechanism of injury most frequently responsible was impact with the sharp nose of the surfboard following a fall. Serious posterior segment complications were observed in all 11 patients, with nine patients suffering ruptured globes. Despite immediate medical attention, five patients did not recover ambulatory levels of visual acuity (>5/200). Surfing-related ocular trauma presenting to the retinal specialist typically leaves the patient with a permanent visual disability. Important factors contributing to these high-velocity injuries include the sharply pointed nose of the surfboard and the leash keeping the surfer in close proximity to the board following a fall. A simple modification in surfboard design such as blunting the sharp nose of the surfboard, or appropriate protective guards fitted over the surfboard nose, should lessen the severity of such injuries.

  20. Public relations activities in BNFL

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, B. [British Nuclear Fuels plc, Cheshire (United Kingdom)

    1993-12-31

    British Nuclear Fuels plc (BNFL) is a major industrial company employing 15,000 people and supporting another 50,000 jobs in British industry through it`s isnvestment program. BNFL is frequently in the news, mainly because of the Sellafield reprocessing plant in West Cumbria. The company`s public relation policy is described in this report.