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Sample records for stress sigma factor

  1. Cross-talk between cognate and noncognate RpoE sigma factors and Zn(2+)-binding anti-sigma factors regulates photooxidative stress response in Azospirillum brasilense.

    Science.gov (United States)

    Gupta, Namrata; Gupta, Ankush; Kumar, Santosh; Mishra, Rajeev; Singh, Chhaya; Tripathi, Anil Kumar

    2014-01-01

    Azospirillum brasilense harbors two redox-sensitive Zinc-binding anti-sigma (ZAS) factors (ChrR1 and ChrR2), which negatively regulate the activity of their cognate extra-cytoplasmic function (ECF) σ factors (RpoE1 and RpoE2) by occluding their binding to the core enzyme. Both pairs of RpoE-ChrR control responses to photooxidative stress. The aim of this study was to investigate whether the two RpoE-ChrR pairs cross-talk while responding to the stress. In silico analysis showed a high sequence similarity between ChrR1 and ChrR2 proteins, but differences in redox sensitivity. Using in silico and in vitro methods of protein-protein interaction, we have shown that both ChrR1 and ChrR2 proteins physically bind to their noncognate RpoE proteins. Restoration of the phenotypes of chrR1::Tn5 and chrR2::Km mutants related to carotenoid biosynthesis and photooxidative stress tolerance by expressing chrR1 or chrR2 provided in vivo evidence for the cross-talk. In addition, up- or down-regulation of several identical proteins by expressing chrR1 or chrR2 in the chrR1::Tn5 mutant provided another in vivo evidence for the cross-talk. Although multiple redox-sensitive ZAS anti-σ factors occur in some Gram-positive bacteria, no cross-talk is reported among them. We report here, for the first time, that the two ZAS anti-σ factors of A. brasilense also interact with their noncognate σ factors and affect gene expression. The two redox-sensitive ZAS anti-σ factors in A. brasilense may interact with their cognate as well as noncognate ECF σ factors to play an important role in redox homeostasis by facilitating recovery from the oxidative stress.

  2. Transcriptional regulation of the operon encoding stress-responsive ECF sigma factor SigH and its anti-sigma factor RshA, and control of its regulatory network in Corynebacterium glutamicum.

    Science.gov (United States)

    Busche, Tobias; Silar, Radoslav; Pičmanová, Martina; Pátek, Miroslav; Kalinowski, Jörn

    2012-09-03

    The expression of genes in Corynebacterium glutamicum, a Gram-positive non-pathogenic bacterium used mainly for the industrial production of amino acids, is regulated by seven different sigma factors of RNA polymerase, including the stress-responsive ECF-sigma factor SigH. The sigH gene is located in a gene cluster together with the rshA gene, putatively encoding an anti-sigma factor. The aim of this study was to analyze the transcriptional regulation of the sigH and rshA gene cluster and the effects of RshA on the SigH regulon, in order to refine the model describing the role of SigH and RshA during stress response. Transcription analyses revealed that the sigH gene and rshA gene are cotranscribed from four sigH housekeeping promoters in C. glutamicum. In addition, a SigH-controlled rshA promoter was found to only drive the transcription of the rshA gene. To test the role of the putative anti-sigma factor gene rshA under normal growth conditions, a C. glutamicum rshA deletion strain was constructed and used for genome-wide transcription profiling with DNA microarrays. In total, 83 genes organized in 61 putative transcriptional units, including those previously detected using sigH mutant strains, exhibited increased transcript levels in the rshA deletion mutant compared to its parental strain. The genes encoding proteins related to disulphide stress response, heat stress proteins, components of the SOS-response to DNA damage and proteasome components were the most markedly upregulated gene groups. Altogether six SigH-dependent promoters upstream of the identified genes were determined by primer extension and a refined consensus promoter consisting of 45 original promoter sequences was constructed. The rshA gene codes for an anti-sigma factor controlling the function of the stress-responsive sigma factor SigH in C. glutamicum. Transcription of rshA from a SigH-dependent promoter may serve to quickly shutdown the SigH-dependent stress response after the cells have

  3. Transcriptional regulation of the operon encoding stress-responsive ECF sigma factor SigH and its anti-sigma factor RshA, and control of its regulatory network in Corynebacterium glutamicum

    Directory of Open Access Journals (Sweden)

    Busche Tobias

    2012-09-01

    Full Text Available Abstract Background The expression of genes in Corynebacterium glutamicum, a Gram-positive non-pathogenic bacterium used mainly for the industrial production of amino acids, is regulated by seven different sigma factors of RNA polymerase, including the stress-responsive ECF-sigma factor SigH. The sigH gene is located in a gene cluster together with the rshA gene, putatively encoding an anti-sigma factor. The aim of this study was to analyze the transcriptional regulation of the sigH and rshA gene cluster and the effects of RshA on the SigH regulon, in order to refine the model describing the role of SigH and RshA during stress response. Results Transcription analyses revealed that the sigH gene and rshA gene are cotranscribed from four sigH housekeeping promoters in C. glutamicum. In addition, a SigH-controlled rshA promoter was found to only drive the transcription of the rshA gene. To test the role of the putative anti-sigma factor gene rshA under normal growth conditions, a C. glutamicum rshA deletion strain was constructed and used for genome-wide transcription profiling with DNA microarrays. In total, 83 genes organized in 61 putative transcriptional units, including those previously detected using sigH mutant strains, exhibited increased transcript levels in the rshA deletion mutant compared to its parental strain. The genes encoding proteins related to disulphide stress response, heat stress proteins, components of the SOS-response to DNA damage and proteasome components were the most markedly upregulated gene groups. Altogether six SigH-dependent promoters upstream of the identified genes were determined by primer extension and a refined consensus promoter consisting of 45 original promoter sequences was constructed. Conclusions The rshA gene codes for an anti-sigma factor controlling the function of the stress-responsive sigma factor SigH in C. glutamicum. Transcription of rshA from a SigH-dependent promoter may serve to quickly

  4. Transcriptional regulation of the operon encoding stress-responsive ECF sigma factor SigH and its anti-sigma factor RshA, and control of its regulatory network in Corynebacterium glutamicum

    Czech Academy of Sciences Publication Activity Database

    Busche, T.; Šilar, Radoslav; Pičmanová, Martina; Pátek, Miroslav; Kalinowski, J.

    2012-01-01

    Roč. 13, č. 445 (2012), s. 445-464 ISSN 1471-2164 R&D Projects: GA ČR GC204/09/J015 Institutional research plan: CEZ:AV0Z50200510 Keywords : Corynebacterium glutamicum * ECF sigma factor * Anti-sigma factor Subject RIV: EE - Microbiology, Virology Impact factor: 4.397, year: 2012

  5. Identification of Disulphide Stress-responsive Extracytoplasmic Function Sigma Factors in Rothia mucilaginosa

    Science.gov (United States)

    2013-01-01

    Senadheera MD, Lee AWC, Hung DCI, Spatafora GA, Goodman SD, Cvitkovitch DG. The Streptococcus mutans vicX gene product modulates gtfB/C expression, biofilm...Involvement of sensor kinases in the stress tolerance response of Streptococcus mutans . Journal of Bacteriology 2008;190(1):68–77. 18. Meuric V...structures from a persistent apical periodontitis lesion. Sequencing 2010;2010:457236. 15. Wen ZT, Burne RA. LuxS-mediated signaling in Streptococcus

  6. Definition of the sigma(W) Regulon of Bacillus subtilis in the Absence of Stress

    NARCIS (Netherlands)

    Zweers, Jessica C.; Nicolas, Pierre; Wiegert, Thomas; van Dijl, Jan Maarten; Denham, Emma L.

    2012-01-01

    Bacteria employ extracytoplasmic function (ECF) sigma factors for their responses to environmental stresses. Despite intensive research, the molecular dissection of ECF sigma factor regulons has remained a major challenge due to overlaps in the ECF sigma factor-regulated genes and the stimuli that

  7. RpoH2 sigma factor controls the photooxidative stress response in a non-photosynthetic rhizobacterium, Azospirillum brasilense Sp7.

    Science.gov (United States)

    Kumar, Santosh; Rai, Ashutosh Kumar; Mishra, Mukti Nath; Shukla, Mansi; Singh, Pradhyumna Kumar; Tripathi, Anil Kumar

    2012-12-01

    Bacteria belonging to the Alphaproteobacteria normally harbour multiple copies of the heat shock sigma factor (known as σ(32), σ(H) or RpoH). Azospirillum brasilense, a non-photosynthetic rhizobacterium, harbours five copies of rpoH genes, one of which is an rpoH2 homologue. The genes around the rpoH2 locus in A. brasilense show synteny with that found in rhizobia. The rpoH2 of A. brasilense was able to complement the temperature-sensitive phenotype of the Escherichia coli rpoH mutant. Inactivation of rpoH2 in A. brasilense results in increased sensitivity to methylene blue and to triphenyl tetrazolium chloride (TTC). Exposure of A. brasilense to TTC and the singlet oxygen-generating agent methylene blue induced several-fold higher expression of rpoH2. Comparison of the proteome of A. brasilense with its rpoH2 deletion mutant and with an A. brasilense strain overexpressing rpoH2 revealed chaperone GroEL, elongation factors (Ef-Tu and EF-G), peptidyl prolyl isomerase, and peptide methionine sulfoxide reductase as the major proteins whose expression was controlled by RpoH2. Here, we show that the RpoH2 sigma factor-controlled photooxidative stress response in A. brasilense is similar to that in the photosynthetic bacterium Rhodobacter sphaeroides, but that RpoH2 is not involved in the detoxification of methylglyoxal in A. brasilense.

  8. Stress-response sigma factor sigH is essential for morphological differentiation of Streptomyces coelicolor A3(2)

    Czech Academy of Sciences Publication Activity Database

    Ševčíková, B.; Benada, Oldřich; Kofroňová, Olga; Kormanec, J.

    2001-01-01

    Roč. 177, - (2001), s. 98-106 ISSN 0302-8933 R&D Projects: GA ČR GA204/98/0421; GA AV ČR IAA5020903; GA AV ČR IPP1043020 Institutional research plan: CEZ:AV0Z5020903 Keywords : Streptomyces * stress response * RNA polymerase Subject RIV: EE - Microbiology, Virology Impact factor: 2.156, year: 2001

  9. Sigma factors and promoters in Corynebacterium glutamicum

    Czech Academy of Sciences Publication Activity Database

    Pátek, Miroslav; Nešvera, Jan

    2011-01-01

    Roč. 154, 2-3 (2011), s. 101-113 ISSN 0168-1656 R&D Projects: GA ČR GC204/09/J015 Institutional research plan: CEZ:AV0Z50200510 Keywords : Corynebacterium glutamicum * Sigma factors * Promoters Subject RIV: EE - Microbiology, Virology Impact factor: 3.045, year: 2011

  10. Extracytoplasmic function sigma factors in Pseudomonas syringae

    DEFF Research Database (Denmark)

    Kiil, Kristoffer; Oguiza, J.A.; Ussery, D.W.

    2005-01-01

    Genome analyses of the plant pathogens Pseudomonas syringae pv. tomato DC3000, pv. syringae B728a and pv. phaseolicola 1448A reveal fewer extracytoplasmic function (ECF) sigma factors than in related Pseudomonads with different lifestyles. We highlight the presence of a P. syringae-specific ECF...

  11. How the early sporulation sigma factor sigmaF delays the switch to late development in Bacillus subtilis.

    Science.gov (United States)

    Karmazyn-Campelli, Céline; Rhayat, Lamya; Carballido-López, Rut; Duperrier, Sandra; Frandsen, Niels; Stragier, Patrick

    2008-03-01

    Sporulation in Bacillus subtilis is a primitive differentiation process involving two cell types, the forespore and the mother cell. Each cell implements two successive transcription programmes controlled by specific sigma factors. We report that activity of sigma(G), the late forespore sigma factor, is kept in check by Gin, the product of csfB, a gene controlled by sigma(F), the early forespore sigma factor. Gin abolishes sigma(G) transcriptional activity when sigma(G) is artificially synthesized during growth, but has no effect on sigma(F). Gin interacts strongly with sigma(G) but not with sigma(F) in a yeast two-hybrid experiment. The absence of Gin allows sigma(G) to be active during sporulation independently of the mother-cell development to which it is normally coupled. Premature sigma(G) activity leads to the formation of slow-germinating spores, and complete deregulation of sigma(G) synthesis is lethal when combined with gin inactivation. Gin allows sigma(F) to delay the switch to the late forespore transcription programme by preventing sigma(G) to take over before the cell has reached a critical stage of development. A similar strategy, following a completely unrelated route, is used by the mother cell.

  12. Interaction of sigma factor sigmaN with Escherichia coli RNA polymerase core enzyme.

    Science.gov (United States)

    Scott, D J; Ferguson, A L; Gallegos, M T; Pitt, M; Buck, M; Hoggett, J G

    2000-12-01

    The equilibrium binding and kinetics of assembly of the DNA-dependent RNA polymerase (RNAP) sigma(N)-holoenzyme has been investigated using biosynthetically labelled 7-azatryptophyl- (7AW)sigma(N). The spectroscopic properties of such 7AW proteins allows their absorbance and fluorescence to be monitored selectively, even in the presence of high concentrations of other tryptophan-containing proteins. The 7AWsigma(N) retained its biological activity in stimulating transcription from sigma(N)-specific promoters, and in in vitro gel electrophoresis assays of binding to core RNAP from Escherichia coli. Furthermore, five Trp-->Ala single mutants of sigma(N) were shown to support growth under conditions of nitrogen limitation, and showed comparable efficiency in activating the sigma(N)-dependent nifH promoter in vivo, indicating that none of the tryptophan residues were essential for activity. The equilibrium binding of 7AWsigma(N) to core RNAP was examined by analytical ultracentrifugation. In sedimentation equilibrium experiments, absorbance data at 315 nm (which reports selectively on the distribution of free and bound 7AWsigma(N)) established that a 1:1 complex was formed, with a dissociation constant lower than 2 microM. The kinetics of the interaction between 7AWsigma(N) and core RNAP was investigated using stopped-flow spectrofluorimetry. A biphasic decrease in fluorescence intensity was observed when samples were excited at 280 nm, whereas only the slower of the two phases was observed at 315 nm. The kinetic data were analysed in terms of a mechanism in which a fast bimolecular association of sigma(N) with core RNAP is followed by a relatively slow isomerization step. The consequences of these findings on the competition between sigma(N) and the major sigma factor, sigma(70), in Escherichia coli are discussed.

  13. Identification and characterization of sigma, a novel component of the Staphylococcus aureus stress and virulence responses.

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    Lindsey N Shaw

    Full Text Available S. aureus is a highly successful pathogen that is speculated to be the most common cause of human disease. The progression of disease in S. aureus is subject to multi-factorial regulation, in response to the environments encountered during growth. This adaptive nature is thought to be central to pathogenesis, and is the result of multiple regulatory mechanisms employed in gene regulation. In this work we describe the existence of a novel S. aureus regulator, an as yet uncharacterized ECF-sigma factor (sigma(S, that appears to be an important component of the stress and pathogenic responses of this organism. Using biochemical approaches we have shown that sigma(S is able to associates with core-RNAP, and initiate transcription from its own coding region. Using a mutant strain we determined that sigma(S is important for S. aureus survival during starvation, extended exposure to elevated growth temperatures, and Triton X-100 induced lysis. Coculture studies reveal that a sigma(S mutant is significantly outcompeted by its parental strain, which is only exacerbated during prolonged growth (7 days, or in the presence of stressor compounds. Interestingly, transcriptional analysis determined that under standard conditions, S. aureus SH1000 does not initiate expression of sigS. Assays performed hourly for 72 h revealed expression in typically background ranges. Analysis of a potential anti-sigma factor, encoded downstream of sigS, revealed it to have no obvious role in the upregulation of sigS expression. Using a murine model of septic arthritis, sigS-mutant infected animals lost significantly less weight, developed septic arthritis at significantly lower levels, and had increased survival rates. Studies of mounted immune responses reveal that sigS-mutant infected animals had significantly lower levels of IL-6, indicating only a weak immunological response. Finally, strains of S. aureus lacking sigS were far less able to undergo systemic dissemination

  14. Six sigma critical success factors in manufacturing industries

    Science.gov (United States)

    Mustafa, Zainol; Jamaluddin, Z.

    2017-04-01

    The success of Six Sigma implementation is known to depend on a number of contributing factors. The purpose of this paper is to explore Six Sigma critical success factors (CSFs) in the context of Malaysian manufacturing organizations. Although Six Sigma success factors have been abundantly researched in the global context, in this paper, a maiden attempt is made to identify, through an extensive literature review, the CSFs for Six Sigma implementation followed by their validation using primary data collection from Malaysian manufacturing companies. A total of 33 indicators have thus been compiled through an extensive literature review which then been grouped into 6 contributing factors. These contributing success factors are then validated through an empirical research of selected Malaysian manufacturing companies at various stages of implementation of the Six Sigma process improvement methodology. There has been an overemphasis on the role and commitment of the management in the success of a Six Sigma program. Though it is undoubted, certain other factors also play an equally important role in ensuring that the Six Sigma programs are successful. The factor analysis of CSFs of the Malaysian manufacturing organizations selected in this study demonstrates that the top factor is a composite factor showing combination of the ability of the project teams to use the process management on quality initiative and a training using a proper analysis in problem solving. The CSFs extracted through the factor analysis could provide a basis for manufacturing organizations embarking on the Six Sigma journey to look beyond just management involvement. Thus, one can develop an integrated framework of other factors as outlined and give them appropriate priority and focus.

  15. Mapping temperature-induced conformational changes in the Escherichia coli heat shock transcription factor sigma 32 by amide hydrogen exchange

    DEFF Research Database (Denmark)

    Rist, Wolfgang; Jørgensen, Thomas J D; Roepstorff, Peter

    2003-01-01

    Stress conditions such as heat shock alter the transcriptional profile in all organisms. In Escherichia coli the heat shock transcription factor, sigma 32, out-competes upon temperature up-shift the housekeeping sigma-factor, sigma 70, for binding to core RNA polymerase and initiates heat shock...... gene transcription. To investigate possible heat-induced conformational changes in sigma 32 we performed amide hydrogen (H/D) exchange experiments under optimal growth and heat shock conditions combined with mass spectrometry. We found a rapid exchange of around 220 of the 294 amide hydrogens at 37...... degrees C, indicating that sigma 32 adopts a highly flexible structure. At 42 degrees C we observed a slow correlated exchange of 30 additional amide hydrogens and localized it to a helix-loop-helix motif within domain sigma 2 that is responsible for the recognition of the -10 region in heat shock...

  16. Characterization and in vivo regulon determination of an ECF sigma factor and its cognate anti-sigma factor in Nostoc punctiforme.

    Science.gov (United States)

    Bell, Nicole; Lee, Jamie J; Summers, Michael L

    2017-04-01

    Based on primary sequence comparisons and genomic context, Npun_F4153 (SigG)/Npun_F4154 (SapG) of the cyanobacterium Nostoc punctiforme were hypothesized to encode an ECF sigma factor/anti-sigma factor pair. Transcription of sigG increased in heterocysts and akinetes, and after EDTA treatment. Interaction between SigG and the predicted cytoplasmic domain of SapG was observed in vitro. A SigG-GFP translational fusion protein localized to the periphery of vegetative cells in vivo, but lost this association following heat stress. A sigG mutant was unable to survive envelope damage caused by heat or EDTA, but was able to form functional heterocysts. Akinetes in the mutant strain appeared normal, but these cultures were less resistant to lysozyme and cold treatments than those of the wild-type strain. The SigG in vivo regulon was determined before and during akinete differentiation using DNA microarray analysis, and found to include multiple genes with putative association to the cell envelope. Mapped promoters common to both arrays enabled identification of a SigG promoter-binding motif that was supported in vivo by reporter studies, and in vitro by run-off transcription experiments. These findings support SigG/SapG as a sigma/anti-sigma pair involved in repair of envelope damage resulting from exogenous sources or cellular differentiation. © 2017 John Wiley & Sons Ltd.

  17. Sigma factors in a thousand E. coli genomes

    DEFF Research Database (Denmark)

    Cook, Helen Victoria; Ussery, David

    2013-01-01

    , 2013), only less than half (983) are of sufficient quality to use in comparative genomic work. Unfortunately, even some of the ‘complete’ E. coli genomes are in pieces, and a few ‘draft’ genomes are good quality. Six of the seven known sigma factors in E. coli strain K‐12 are extremely well conserved...

  18. Tripod sigma: results of a pro-active work stress-survey

    NARCIS (Netherlands)

    Nelemans, R.; Wiezer, N.; Vaas, F.; Gort, J.; Groeneweg, J.

    2003-01-01

    Work related stress is an important causes of disability and absenteeism. TNO Work and Employment has developed an instrument, called Tripod Sigma, that identifies risks to work stress and provides tools for remedying these risks. The Tripod Sigma model is developed analogous to the Tripod

  19. Genome-scale reconstruction of the sigma factor network in Escherichia coli: topology and functional states

    DEFF Research Database (Denmark)

    Cho, Byung-Kwan; Kim, Donghyuk; Knight, Eric M.

    2014-01-01

    Background: At the beginning of the transcription process, the RNA polymerase (RNAP) core enzyme requires a sigma-factor to recognize the genomic location at which the process initiates. Although the crucial role of sigma-factors has long been appreciated and characterized for many individual...... to transcription units (TUs), representing an increase of more than 300% over what has been previously reported. The reconstructed network was used to investigate competition between alternative sigma-factors (the sigma(70) and sigma(38) regulons), confirming the competition model of sigma substitution...

  20. Effect of extracytoplasmic function sigma factors on autoaggregation, hemagglutination, and cell surface properties of Porphyromonas gingivalis

    Science.gov (United States)

    Kokubu, Eitoyo; Okamoto-Shibayama, Kazuko; Ishihara, Kazuyuki

    2017-01-01

    Porphyromonas gingivalis is a bacterium frequently isolated from chronic periodontal lesions and is involved in the development of chronic periodontitis. To colonize the gingival crevice, P. gingivalis has to adapt to environmental stresses. Microbial gene expression is regulated by transcription factors such as those in two-component systems and extracytoplasmic function (ECF) sigma factors. ECF sigma factors are involved in the regulation of environmental stress response genes; however, the roles of individual ECF sigma factors are largely unknown. The purpose of this study was to investigate the functions, including autoaggregation, hemagglutination, gingipain activity, susceptibility to antimicrobial agents, and surface structure formation, of P. gingivalis ECF sigma factors encoded by SigP (PGN_0274), SigCH (PGN_0319), PGN_0450, PGN_0970, and SigH (PGN_1740). Various physiological aspects of the sigP mutant were affected; autoaggregation was significantly decreased at 60 min (p < 0.001), hemagglutination activity was markedly reduced, and enzymatic activities of Kgp and Rgps were significantly decreased (p < 0.001). The other mutants also showed approximately 50% reduction in Rgps activity. Kgp activity was significantly reduced in the sigH mutant (p < 0.001). No significant differences in susceptibilities to tetracycline and ofloxacin were observed in the mutants compared to those of the wild-type strain. However, the sigP mutant displayed an increased susceptibility to ampicillin, whereas the PGN_0450 and sigH mutants showed reduced susceptibility. Transmission electron microscopy images revealed increased levels of outer membrane vesicles formed at the cell surfaces of the sigP mutant. These results indicate that SigP is important for bacterial surface-associated activities, including gingipain activity, autoaggregation, hemagglutination, vesicle formation, and antimicrobial susceptibility. PMID:28931045

  1. An extracytoplasmic function sigma factor cotranscribed with its cognate anti-sigma factor confers tolerance to NaCl, ethanol and methylene blue in Azospirillum brasilense Sp7.

    Science.gov (United States)

    Mishra, Mukti Nath; Kumar, Santosh; Gupta, Namrata; Kaur, Simarjot; Gupta, Ankush; Tripathi, Anil K

    2011-04-01

    Azospirillum brasilense, a plant-growth-promoting rhizobacterium, is exposed to changes in its abiotic environment, including fluctuations in temperature, salinity, osmolarity, oxygen concentration and nutrient concentration, in the rhizosphere and in the soil. Since extra-cytoplasmic function (ECF) sigma factors play an important role in stress adaptation, we analysed the role of ECF sigma factor (also known as RpoE or σ(E)) in abiotic stress tolerance in A. brasilense. An in-frame rpoE deletion mutant of A. brasilense Sp7 was carotenoidless and slow-growing, and was sensitive to salt, ethanol and methylene blue stress. Expression of rpoE in the rpoE deletion mutant complemented the defects in growth, carotenoid biosynthesis and sensitivity to different stresses. Based on data from reverse transcriptase-PCR, a two-hybrid assay and a pull-down assay, we present evidence that rpoE is cotranscribed with chrR and the proteins synthesized from these two overlapping genes interact with each other. Identification of the transcription start site by 5' rapid amplification of cDNA ends showed that the rpoE-chrR operon was transcribed by two promoters. The proximal promoter was less active than the distal promoter, whose consensus sequence was characteristic of RpoE-dependent promoters found in alphaproteobacteria. Whereas the proximal promoter was RpoE-independent and constitutively expressed, the distal promoter was RpoE-dependent and strongly induced in response to stationary phase and elevated levels of ethanol, salt, heat and methylene blue. This study shows the involvement of RpoE in controlling carotenoid synthesis as well as in tolerance to some abiotic stresses in A. brasilense, which might be critical in the adaptation, survival and proliferation of this rhizobacterium in the soil and rhizosphere under stressful conditions.

  2. The alternative sigma factor sigma B of Staphylococcus aureus modulates virulence in experimental central venous catheter-related infections.

    Science.gov (United States)

    Lorenz, Udo; Hüttinger, Christian; Schäfer, Tina; Ziebuhr, Wilma; Thiede, Arnulf; Hacker, Jörg; Engelmann, Susanne; Hecker, Michael; Ohlsen, Knut

    2008-03-01

    The impact of the alternative sigma factor sigma B (SigB) on pathogenesis of Staphylococcus aureus is not conclusively clarified. In this study, a central venous catheter (CVC) related model of multiorgan infection was used to investigate the role of SigB for the pathogenesis of S. aureus infections and biofilm formation in vivo. Analysis of two SigB-positive wild-type strains and their isogenic mutants revealed uniformly that the wild-type was significantly more virulent than the SigB-deficient mutant. The observed difference in virulence was apparently not linked to the capability of the strains to form biofilms in vivo since wild-type and mutant strains were able to produce biofilm layers inside of the catheter. The data strongly indicate that the alternative sigma factor SigB plays a role in CVC-associated infections caused by S. aureus.

  3. Six Sigma: Problems, Limitations, Critical Success Factors and Future Prospects

    Directory of Open Access Journals (Sweden)

    Paulo Mazieiro Pohlmann

    2015-12-01

    Full Text Available Six Sigma is a business strategy based on objective decision making and problem solving in order to achieve, maintain and maximize business success through understanding and meeting the needs of customers. The visualization of this methodology as a powerful tool in reducing variability and improving quality led to the interest in performing this bibliographical study, whose purpose was to assess the critical success factors and future prospects of this managerial system. A survey was conducted in order to discover the main critical success factors of the implementation of the methodology in organizations, among which stood out the proper selection of projects, connecting the project with the business strategy, customer focus, financial, human and infrastructure resources, the involvement of senior management, professional training, and cultural change.

  4. Sigma-1 receptor chaperone and brain-derived neurotrophic factor: emerging links between cardiovascular disease and depression.

    Science.gov (United States)

    Hashimoto, Kenji

    2013-01-01

    Epidemiological studies have demonstrated a close relationship between depression and cardiovascular disease (CVD). Although it is known that the central nervous system (CNS) contributes to this relationship, the detailed mechanisms involved in this process remain unclear. Recent studies suggest that the endoplasmic reticulum (ER) molecular chaperone sigma-1 receptor and brain-derived neurotrophic factor (BDNF) play a role in the pathophysiology of CVD and depression. Several meta-analysis studies have showed that levels of BDNF in the blood of patients with major depressive disorder (MDD) are lower than normal controls, indicating that blood BDNF might be a biomarker for depression. Furthermore, blood levels of BDNF in patients with CVD are also lower than normal controls. A recent study using conditional BDNF knock-out mice in animal models of myocardial infarction highlighted the role of CNS-mediated mechanisms in the cardioprotective effects of BDNF. In addition, a recent study shows that decreased levels of sigma-1 receptor in the mouse brain contribute to the association between heart failure and depression. Moreover, sigma-1 receptor agonists, including the endogenous neurosteroid dehydroepiandosterone (DHEA) and the selective serotonin reuptake inhibitor (SSRI) fluvoxamine, show potent cardioprotective and antidepressive effects in rodents, via sigma-1 receptor stimulation. Interestingly, agonist activation of sigma-1 receptors increased the secretion of mature BDNF from its precursor proBDNF via chaperone activity in the ER. Given the role of ER stress in the pathophysiology of CVD and MDD, the author will discuss the potential link between sigma-1 receptors and BDNF-TrkB pathway in the pathophysiology of these two diseases. Finally, the author will make a case for potent sigma-1 receptor agonists and TrkB agonists as new potential therapeutic drugs for depressive patients with CVD. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Bacillus subtilis extracytoplasmic function (ECF) sigma factors and defense of the cell envelope.

    Science.gov (United States)

    Helmann, John D

    2016-04-01

    Bacillus subtilis provides a model for investigation of the bacterial cell envelope, the first line of defense against environmental threats. Extracytoplasmic function (ECF) sigma factors activate genes that confer resistance to agents that threaten the integrity of the envelope. Although their individual regulons overlap, σ(W) is most closely associated with membrane-active agents, σ(X) with cationic antimicrobial peptide resistance, and σ(V) with resistance to lysozyme. Here, I highlight the role of the σ(M) regulon, which is strongly induced by conditions that impair peptidoglycan synthesis and includes the core pathways of envelope synthesis and cell division, as well as stress-inducible alternative enzymes. Studies of these cell envelope stress responses provide insights into how bacteria acclimate to the presence of antibiotics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Carotenoid Biosynthetic Pathways Are Regulated by a Network of Multiple Cascades of Alternative Sigma Factors in Azospirillum brasilense Sp7.

    Science.gov (United States)

    Rai, Ashutosh Kumar; Dubey, Ashutosh Prakash; Kumar, Santosh; Dutta, Debashis; Mishra, Mukti Nath; Singh, Bhupendra Narain; Tripathi, Anil Kumar

    2016-11-01

    Carotenoids constitute an important component of the defense system against photooxidative stress in bacteria. In Azospirillum brasilense Sp7, a nonphotosynthetic rhizobacterium, carotenoid synthesis is controlled by a pair of extracytoplasmic function sigma factors (RpoEs) and their cognate zinc-binding anti-sigma factors (ChrRs). Its genome harbors two copies of the gene encoding geranylgeranyl pyrophosphate synthase (CrtE), the first critical step in the carotenoid biosynthetic pathway in bacteria. Inactivation of each of two crtE paralogs found in A. brasilense caused reduction in carotenoid content, suggesting their involvement in carotenoid synthesis. However, the effect of crtE1 deletion was more pronounced than that of crtE2 deletion. Out of the five paralogs of rpoH in A. brasilense, overexpression of rpoH1 and rpoH2 enhanced carotenoid synthesis. Promoters of crtE2 and rpoH2 were found to be dependent on RpoH2 and RpoE1, respectively. Using a two-plasmid system in Escherichia coli, we have shown that the crtE2 gene of A. brasilense Sp7 is regulated by two cascades of sigma factors: one consisting of RpoE1and RpoH2 and the other consisting of RpoE2 and RpoH1. In addition, expression of crtE1 was upregulated indirectly by RpoE1 and RpoE2. This study shows, for the first time in any carotenoid-producing bacterium, that the regulation of carotenoid biosynthetic pathway involves a network of multiple cascades of alternative sigma factors. Carotenoids play a very important role in coping with photooxidative stress in prokaryotes and eukaryotes. Although extracytoplasmic function (ECF) sigma factors are known to directly regulate the expression of carotenoid biosynthetic genes in bacteria, regulation of carotenoid biosynthesis by one or multiple cascades of sigma factors had not been reported. This study provides the first evidence of the involvement of multiple cascades of sigma factors in the regulation of carotenoid synthesis in any bacterium by showing the

  7. Induction of a stable sigma factor SigR by translation-inhibiting antibiotics confers resistance to antibiotics

    OpenAIRE

    Yoo, Ji-Sun; Oh, Gyeong-Seok; Ryoo, Sungweon; Roe, Jung-Hye

    2016-01-01

    Antibiotic-producing streptomycetes are rich sources of resistance mechanisms against endogenous and exogenous antibiotics. An ECF sigma factor ?R (SigR) is known to govern the thiol-oxidative stress response in Streptomyces coelicolor. Amplification of this response is achieved by producing an unstable isoform of ?R called ?R?. In this work, we present evidence that antibiotics induce the SigR regulon via a redox-independent pathway, leading to antibiotic resistance. The translation-inhibiti...

  8. Sigma factors, asymmetry, and the determination of cell fate in Bacillus subtilis.

    OpenAIRE

    Lewis, P J; Partridge, S R; Errington, J

    1994-01-01

    Soon after the initiation of sporulation, Bacillus subtilis divides asymmetrically to produce sister cells that have very different developmental fates. Recently, it has been proposed that the differential gene expression which begins soon after this division is due to cell-specific activation of the transcription factors sigma F and sigma E in the prespore and the mother cell, respectively. We describe the use of a method for the localization of gene expression in individual sporulating cell...

  9. Selection of unusual actinomycetal primary sigma70 factors by plant-colonizing Frankia strains.

    Science.gov (United States)

    Lavire, Céline; Blaha, Didier; Cournoyer, Benoit

    2004-02-01

    Functional adaptations of sigma70 transcriptional factors led to the emergence of several paralogous lineages, each one being specialized for gene transcription under particular growth conditions. Screening of a Frankia strain EaI-12 gene library by sigma70 DNA probing allowed the detection and characterization of a novel actinomycetal primary (housekeeping) sigma70 factor. Phylogenetic analysis positioned this factor in the RpoD cluster of proteobacterial and low-G+C-content gram-positive factors, a cluster previously free of any actinobacterial sequences. sigma70 DNA probing of Frankia total DNA blots and PCR screening detected one or two rpoD-like DNA regions per species. rpoD matched the conserved region in all of the species tested. The other region was found to contain sigA, an alternative primary factor. sigA appeared to be strictly distributed among Frankia species infecting plants by the root hair infection process. Both genes were transcribed by Frankia strain ACN14a grown in liquid cultures. The molecular phylogeny of the sigma70 family determined with Frankia sequences showed that the alternative actinomycetal factors and the essential ones belonged to the same radiation. At least seven distinct paralogous lineages were observed among this radiation, and gene transfers were detected in the HrdB actinomycetal lineage.

  10. Physiological roles of sigma factor SigD in Corynebacterium glutamicum

    Czech Academy of Sciences Publication Activity Database

    Taniguchi, H.; Busche, T.; Patschkowski, T.; Niehaus, K.; Pátek, Miroslav; Kalinowski, J.; Wendisch, V.F.

    2017-01-01

    Roč. 17, č. 158 (2017), s. 158 ISSN 1471-2180 R&D Projects: GA ČR(CZ) GA17-06991S Institutional support: RVO:61388971 Keywords : Corynebacterium glutamicum * Sigma factor * SigD Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.644, year: 2016

  11. Assignment of sigma factors of RNA polymerase to promoters in Corynebacterium glutamicum

    Czech Academy of Sciences Publication Activity Database

    Dostálová, Hana; Holátko, Jiří; Busche, T.; Rucká, Lenka; Rapoport, Andrey; Halada, Petr; Nešvera, Jan; Kalinowski, J.; Pátek, Miroslav

    2017-01-01

    Roč. 7, JUN 23 (2017), s. 1-13, č. článku 133. ISSN 2191-0855 R&D Projects: GA ČR(CZ) GA17-06991S Institutional support: RVO:61388971 Keywords : Corynebacterium glutamicum * Promoter * Sigma factor Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.825, year: 2016

  12. Improving furfural tolerance of Zymomonas mobilis by rewiring a sigma factor RpoD protein.

    Science.gov (United States)

    Tan, Fu-Rong; Dai, Li-Chun; Wu, Bo; Qin, Han; Shui, Zong-Xia; Wang, Jing-Li; Zhu, Qi-Li; Hu, Qi-Chun; Ruan, Zhi-Yong; He, Ming-Xiong

    2015-06-01

    Furfural from lignocellulosic hydrolysates is the key inhibitor for bio-ethanol fermentation. In this study, we report a strategy of improving the furfural tolerance in Zymomonas mobilis on the transcriptional level by engineering its global transcription sigma factor (σ(70), RpoD) protein. Three furfural tolerance RpoD mutants (ZM4-MF1, ZM4-MF2, and ZM4-MF3) were identified from error-prone PCR libraries. The best furfural-tolerance strain ZM4-MF2 reached to the maximal cell density (OD600) about 2.0 after approximately 30 h, while control strain ZM4-rpoD reached its highest cell density of about 1.3 under the same conditions. ZM4-MF2 also consumed glucose faster and yield higher ethanol; expression levels and key Entner-Doudoroff (ED) pathway enzymatic activities were also compared to control strain under furfural stress condition. Our results suggest that global transcription machinery engineering could potentially be used to improve stress tolerance and ethanol production in Z. mobilis.

  13. Novel nuclear-encoded proteins interacting with a plastid sigma factor, Sig1, in Arabidopsis thaliana.

    Science.gov (United States)

    Morikawa, Kazuya; Shiina, Takashi; Murakami, Shinya; Toyoshima, Yoshinori

    2002-03-13

    Sigma factor binding proteins are involved in modifying the promoter preferences of the RNA polymerase in bacteria. We found the nuclear encoded protein (SibI) that is transported into chloroplasts and interacts specifically with the region 4 of Sig1 in Arabidopsis. SibI and its homologue, T3K9.5 are novel proteins, which are not homologous to any protein of known function. The expression of sibI was tissue specific, light dependent, and developmentally timed. We suggest the transcriptional regulation by sigma factor binding proteins to function in the plastids of higher plant.

  14. Functional Analysis of the Alternative Sigma-28 Factor FliA and Its Anti-Sigma Factor FlgM of the Nonflagellated Legionella Species L. oakridgensis.

    Science.gov (United States)

    Tlapák, Hana; Rydzewski, Kerstin; Schulz, Tino; Weschka, Dennis; Schunder, Eva; Heuner, Klaus

    2017-06-01

    Legionella oakridgensis causes Legionnaires' disease but is known to be less virulent than Legionella pneumophila L. oakridgensis is one of the Legionella species that is nonflagellated. The genes of the flagellar regulon are absent, except those encoding the alternative sigma-28 factor (FliA) and its anti-sigma-28 factor (FlgM). Similar to L. oakridgensis , Legionella adelaidensis and Legionella londiniensis , located in the same phylogenetic clade, have no flagellar regulon, although both are positive for fliA and flgM Here, we investigated the role and function of both genes to better understand the role of FliA, the positive regulator of flagellin expression, in nonflagellated strains. We demonstrated that the FliA gene of L. oakridgensis encodes a functional sigma-28 factor that enables the transcription start from the sigma-28-dependent promoter site. The investigations have shown that FliA is necessary for full fitness of L. oakridgensis Interestingly, expression of FliA-dependent genes depends on the growth phase and temperature, as already shown for L. pneumophila strains that are flagellated. In addition, we demonstrated that FlgM is a negative regulator of FliA-dependent gene expression. FlgM seems to be degraded in a growth-phase- and temperature-dependent manner, instead of being exported into the medium as reported for most bacteria. The degradation of FlgM leads to an increase of FliA activity. IMPORTANCE A less virulent Legionella species, L. oakridgensis , causes Legionnaires' disease and is known to not have flagella, even though L. oakridgensis has the regulator of flagellin expression (FliA). This protein has been shown to be involved in the expression of virulence factors. Thus, the strain was chosen for use in this investigation to search for FliA target genes and to identify putative virulence factors of L. oakridgensis One of the five major target genes of FliA identified here encodes the anti-FliA sigma factor FlgM. Interestingly, in

  15. Involvement of Pseudomonas putida RpoN sigma factor in regulation of various metabolic functions.

    OpenAIRE

    Köhler, T; Harayama, S; Ramos, J L; Timmis, K N

    1989-01-01

    The RpoN protein was originally identified in Escherichia coli as a sigma (sigma) factor essential for the expression of nitrogen regulons. In the present study we cloned the Pseudomonas putida rpoN gene and identified its gene product as a protein with an apparent molecular weight of 78,000. A mutant rpoN gene was constructed by in vitro insertion mutagenesis with a kanamycin cassette. A P. putida rpoN mutant was then isolated by replacement of the intact chromosomal rpoN gene by the mutant ...

  16. Importance of sigma factor mutations in increased triclosan resistance in Salmonella Typhimurium

    DEFF Research Database (Denmark)

    Gantzhorn, Mette Rørbæk; Olsen, John Elmerdahl; Thomsen, Line Elnif

    2015-01-01

    towards the antibiotics enrofloxacin and sulphamethoxazole/trimethoprim. CONCLUSIONS: Medium level triclosan resistance could be obtained by fabI mutations in S. Typhimurium, however, high level resistance was found to require sigma factor mutations in addition to a fabI mutation. Reduced antibiotic...

  17. Characterization of five ECF sigma factors in the genome of Pseudomonas syringae pv. syringae B728a.

    Directory of Open Access Journals (Sweden)

    Poulami Basu Thakur

    Full Text Available Pseudomonas syringae pv. syringae B728a, a bacterial pathogen of bean, utilizes large surface populations and extracellular signaling to initiate a fundamental change from an epiphytic to a pathogenic lifestyle. Extracytoplasmic function (ECF sigmafactors serve as important regulatory factors in responding to various environmental signals. Bioinformatic analysis of the B728a genome revealed 10 ECF sigma factors. This study analyzed deletion mutants of five previously uncharacterized ECF sigma factor genes in B728a, including three FecI-type ECF sigma factors (ECF5, ECF6, and ECF7 and two ECF sigma factors placed in groups ECF11 and ECF18. Transcriptional profiling by qRT-PCR analysis of ECF sigma factor mutants was used to measure expression of their associated anti-sigma and outer membrane receptor proteins, and expression of genes associated with production of extracellular polysaccharides, fimbriae, glycine betaine and syringomycin. Notably, the B728aΔecf7 mutant displayed reduced swarming and had decreased expression of CupC fimbrial genes. Growth and pathogenicity assays, using a susceptible bean host, revealed that none of the tested sigma factor genes are required for in planta growth and lesion formation.

  18. Anti-sigma factor YlaD regulates transcriptional activity of sigma factor YlaC and sporulation via manganese-dependent redox-sensing molecular switch in Bacillus subtilis.

    Science.gov (United States)

    Kwak, Min-Kyu; Ryu, Han-Bong; Song, Sung-Hyun; Lee, Jin-Won; Kang, Sa-Ouk

    2018-05-14

    YlaD, a membrane-anchored anti-sigma factor of Bacillus subtilis , contains a HX 3 CXXC motif that functions as a redox-sensing domain and belongs to one of the zinc-coordinated anti-sigma factor families. Despite previously showing that the YlaC transcription is controlled by YlaD, experimental evidence of how the YlaC-YlaD interaction is affected by active cysteines and/or metal ions is lacking. Here, we showed that the P yla promoter is autoregulated solely by YlaC. Moreover, reduced YlaD contained zinc and iron, while oxidized YlaD did not. Cysteine substitution in YlaD led to changes in its secondary structure; Cys3 had important structural functions in YlaD, and its mutation caused dissociation from YlaC, indicating the essential requirement of a HX 3 CXXC motif for regulating interactions of YlaC with YlaD. Analyses of the far-UV CD spectrum and metal content revealed that the addition of Mn ions to Zn-YlaD changed its secondary structure and that iron was substituted for manganese. The ylaC gene expression using βGlu activity from P yla : gusA was observed at the late-exponential and early-stationary phase and the ylaC -overexpressing mutant constitutively expressed gene transcripts of clpP and sigH , an important alternative sigma factor regulated by ClpXP. Collectively, our data demonstrated that YlaD senses redox changes and elicits increase in manganese ion concentrations and that, in turn, YlaD-mediated transcriptional activity of YlaC regulates sporulation initiation under oxidative stress and manganese-substituted conditions by regulating clpP gene transcripts. This is the first report of the involvement of oxidative stress-responsive B. subtilis extracytoplasmic function sigma factors during sporulation via a manganese-dependent redox-sensing molecular switch. ©2018 The Author(s).

  19. Form factors in the projected linear chiral sigma model

    International Nuclear Information System (INIS)

    Alberto, P.; Coimbra Univ.; Bochum Univ.; Ruiz Arriola, E.; Fiolhais, M.; Urbano, J.N.; Coimbra Univ.; Goeke, K.; Gruemmer, F.; Bochum Univ.

    1990-01-01

    Several nucleon form factors are computed within the framework of the linear chiral soliton model. To this end variational means and projection techniques applied to generalized hedgehog quark-boson Fock states are used. In this procedure the Goldberger-Treiman relation and a virial theorem for the pion-nucleon form factor are well fulfilled demonstrating the consistency of the treatment. Both proton and neutron charge form factors are correctly reproduced, as well as the proton magnetic one. The shapes of the neutron magnetic and of the axial form factors are good but their absolute values at the origin are too large. The slopes of all the form factors at zero momentum transfer are in good agreement with the experimental data. The pion-nucleon form factor exhibits to great extent a monopole shape with a cut-off mass of Λ=690 MeV. Electromagnetic form factors for the vertex γNΔ and the nucleon spin distribution are also evaluated and discussed. (orig.)

  20. Inference of sigma factor controlled networks by using numerical modeling applied to microarray time series data of the germinating prokaryote.

    Science.gov (United States)

    Strakova, Eva; Zikova, Alice; Vohradsky, Jiri

    2014-01-01

    A computational model of gene expression was applied to a novel test set of microarray time series measurements to reveal regulatory interactions between transcriptional regulators represented by 45 sigma factors and the genes expressed during germination of a prokaryote Streptomyces coelicolor. Using microarrays, the first 5.5 h of the process was recorded in 13 time points, which provided a database of gene expression time series on genome-wide scale. The computational modeling of the kinetic relations between the sigma factors, individual genes and genes clustered according to the similarity of their expression kinetics identified kinetically plausible sigma factor-controlled networks. Using genome sequence annotations, functional groups of genes that were predominantly controlled by specific sigma factors were identified. Using external binding data complementing the modeling approach, specific genes involved in the control of the studied process were identified and their function suggested.

  1. Sinorhizobium meliloti sigma factors RpoE1 and RpoE4 are activated in stationary phase in response to sulfite.

    Directory of Open Access Journals (Sweden)

    Bénédicte Bastiat

    Full Text Available Rhizobia are soil bacteria able to establish a nitrogen-fixing symbiosis with legume plants. Both in soil and in planta, rhizobia spend non-growing periods resembling the stationary phase of in vitro-cultured bacteria. The primary objective of this work was to better characterize gene regulation in this biologically relevant growth stage in Sinorhizobium meliloti. By a tap-tag/mass spectrometry approach, we identified five sigma factors co-purifying with the RNA polymerase in stationary phase: the general stress response regulator RpoE2, the heat shock sigma factor RpoH2, and three extra-cytoplasmic function sigma factors (RpoE1, RpoE3 and RpoE4 belonging to the poorly characterized ECF26 subgroup. We then showed that RpoE1 and RpoE4 i are activated upon metabolism of sulfite-generating compounds (thiosulfate and taurine, ii display overlapping regulatory activities, iii govern a dedicated sulfite response by controlling expression of the sulfite dehydrogenase SorT, iv are activated in stationary phase, likely as a result of endogenous sulfite generation during bacterial growth. We showed that SorT is required for optimal growth of S. meliloti in the presence of sulfite, suggesting that the response governed by RpoE1 and RpoE4 may be advantageous for bacteria in stationary phase either by providing a sulfite detoxification function or by contributing to energy production through sulfite respiration. This paper therefore reports the first characterization of ECF26 sigma factors, the first description of sigma factors involved in control of sulphur metabolism, and the first indication that endogenous sulfite may act as a signal for regulation of gene expression upon entry of bacteria in stationary phase.

  2. The electromagnetic Sigma-to-Lambda hyperon transition form factors at low energies

    International Nuclear Information System (INIS)

    Granados, Carlos; Leupold, Stefan; Perotti, Elisabetta

    2017-01-01

    Using dispersion theory the low-energy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the two-pion-Sigma-Lambda amplitudes are determined from relativistic next-to-leading-order (NLO) baryon chiral perturbation theory including the baryons from the octet and optionally from the decuplet. Pion rescattering is again taken into account by dispersion theory. It turns out that the inclusion of decuplet baryons is not an option but a necessity to obtain reasonable results. The electric transition form factor remains very small in the whole low-energy region. The magnetic transition form factor depends strongly on one not very well determined low-energy constant of the NLO Lagrangian. One obtains reasonable predictive power if this low-energy constant is determined from a measurement of the magnetic transition radius. Such a measurement can be performed at the future Facility for Antiproton and Ion Research (FAIR). (orig.)

  3. The electromagnetic Sigma-to-Lambda hyperon transition form factors at low energies

    Energy Technology Data Exchange (ETDEWEB)

    Granados, Carlos [Uppsala Universitet, Institutionen foer Fysik och Astronomi (Sweden); Jefferson Lab, Newport News, VA (United States); Leupold, Stefan; Perotti, Elisabetta [Uppsala Universitet, Institutionen foer Fysik och Astronomi (Sweden)

    2017-06-15

    Using dispersion theory the low-energy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the two-pion-Sigma-Lambda amplitudes are determined from relativistic next-to-leading-order (NLO) baryon chiral perturbation theory including the baryons from the octet and optionally from the decuplet. Pion rescattering is again taken into account by dispersion theory. It turns out that the inclusion of decuplet baryons is not an option but a necessity to obtain reasonable results. The electric transition form factor remains very small in the whole low-energy region. The magnetic transition form factor depends strongly on one not very well determined low-energy constant of the NLO Lagrangian. One obtains reasonable predictive power if this low-energy constant is determined from a measurement of the magnetic transition radius. Such a measurement can be performed at the future Facility for Antiproton and Ion Research (FAIR). (orig.)

  4. Identification of additional genes under the control of the transcription factor sigma F of Bacillus subtilis.

    OpenAIRE

    Decatur, A; Losick, R

    1996-01-01

    We describe the identification of five transcriptional units under the control of the sporulation transcription factor sigma F in Bacillus subtilis. These are csfA, csfB, csfC, csfD, and csfF, located at approximately 230 degrees, 2 degrees, 316 degrees, 205 degrees, and approximately 290 degrees, respectively, on the genetic map. Null mutations in csfA, csfB, csfC, or csfD, either alone or together, do not cause a noticeable defect in sporulation or germination.

  5. The alternative sigma factor sigmaB and the stress response of Bacillus cereus

    NARCIS (Netherlands)

    Schaik, van W.

    2005-01-01

    cum laude graduation (with distinction) The bacterium Bacillus cereus is responsible for a large number of cases of foodborne illness across the world. It is also an important cause of spoilage of food, in particular of milk and dairy-products. The growth and survival of B. cereus in food or during

  6. The response regulator expM is essential for the virulence of Erwinia carotovora subsp. carotovora and acts negatively on the sigma factor RpoS (sigma s).

    Science.gov (United States)

    Andersson, R A; Palva, E T; Pirhonen, M

    1999-07-01

    The main virulence factors of Erwinia carotovora subsp. carotovora, the secreted, extracellular cell-wall-degrading enzymes, are controlled by several regulatory mechanisms. We have isolated transposon mutants with reduced virulence on tobacco. One of these mutants, with a mutation in a gene designated expM, was characterized in this study. This mutant produces slightly reduced amounts of extracellular enzymes in vitro and the secretion of the enzymes is also affected. The expM wild-type allele was cloned together with an upstream gene, designated expL, that has an unknown function. The expM gene was sequenced and found to encode a protein with similarity to the RssB/SprE protein of Escherichia coli and the MviA protein of Salmonella typhimurium. These proteins belong to a new type of two-component response regulators that negatively regulate the stability of the Sigma factor RpoS (sigma s) at the protein level. The results of this study suggest that ExpM has a similar function in E. carotovora subsp. carotovora. We also provide evidence that the overproduction of RpoS in the expM mutant is an important factor for the reduced virulence phenotype and that it partly causes the observed phenotype seen in vitro. However, an expM/rpoS double mutant is still affected in secretion of extracellular enzymes, suggesting that ExpM in addition to RpoS also acts on other targets.

  7. Roles of SigB and SigF in the Mycobacterium tuberculosis Sigma Factor Network▿ †

    OpenAIRE

    Lee, Jong-Hee; Karakousis, Petros C.; Bishai, William R.

    2007-01-01

    To characterize the roles of SigB and SigF in sigma factor regulation in Mycobacterium tuberculosis, we used chemically inducible recombinant strains to conditionally overexpress sigB and sigF. Using whole genomic microarray analysis and quantitative reverse transcription-PCR, we investigated the resulting global transcriptional changes after sigB induction, and we specifically tested the relative expression of other sigma factor genes after knock-in expression of sigB and sigF. Overexpressio...

  8. Efficient cell-free expression with the endogenous E. Coli RNA polymerase and sigma factor 70

    Directory of Open Access Journals (Sweden)

    Noireaux Vincent

    2010-06-01

    Full Text Available Abstract Background Escherichia coli cell-free expression systems use bacteriophage RNA polymerases, such as T7, to synthesize large amounts of recombinant proteins. These systems are used for many applications in biotechnology, such as proteomics. Recently, informational processes have been reconstituted in vitro with cell-free systems. These synthetic approaches, however, have been seriously limited by a lack of transcription modularity. The current available cell-free systems have been optimized to work with bacteriophage RNA polymerases, which put significant restrictions to engineer processes related to biological information. The development of efficient cell-free systems with broader transcription capabilities is required to study complex informational processes in vitro. Results In this work, an efficient cell-free expression system that uses the endogenous E. coli RNA polymerase only and sigma factor 70 for transcription was prepared. Approximately 0.75 mg/ml of Firefly luciferase and enhanced green fluorescent protein were produced in batch mode. A plasmid was optimized with different regulatory parts to increase the expression. In addition, a new eGFP was engineered that is more translatable in cell-free systems than the original eGFP. The protein production was characterized with three different adenosine triphosphate (ATP regeneration systems: creatine phosphate (CP, phosphoenolpyruvate (PEP, and 3-phosphoglyceric acid (3-PGA. The maximum protein production was obtained with 3-PGA. Preparation of the crude extract was streamlined to a simple routine procedure that takes 12 hours including cell culture. Conclusions Although it uses the endogenous E. coli transcription machinery, this cell-free system can produce active proteins in quantities comparable to bacteriophage systems. The E. coli transcription provides much more possibilities to engineer informational processes in vitro. Many E. coli promoters/operators specific to sigma

  9. The Road Towards Lean Six Sigma: Sustainable Success Factors in Service Industry

    Directory of Open Access Journals (Sweden)

    Vouzas Fotis

    2014-11-01

    Full Text Available It has been widely investigated that the application of operations management techniques is not only based on technical factors, but it is mainly associated with organisational factors such as culture, previous polices and procedures, etc. A prime example of promisng operations practices is Lean Six Sigma (L6σ. The main research question for L6σ is related to its liabilities and constrains regarding its implementation. Therefore, this paper aims to explore the critical factors related to the application L6σ. The context of the analysis is service industry since it seems that it has been neglected from the literature that mainly focuses on manufacturing. The methodology was based on the qualitative exploration of three case studies from the service industry. Secondary data were collected through an analysis of companies' documents, written procedures and quality assurance policies and primary data were collected through a number of in-depth face-to-face interviews with managers and quality experts. The findings show that there are ten (10 particular factors that influence the implementation of L6σ in service organizations.

  10. Activation of the sigma-1 receptor by haloperidol metabolites facilitates brain-derived neurotrophic factor secretion from human astroglia.

    Science.gov (United States)

    Dalwadi, Dhwanil A; Kim, Seongcheol; Schetz, John A

    2017-05-01

    Glial cells play a critical role in neuronal support which includes the production and release of the neurotrophin brain-derived neurotrophic factor (BDNF). Activation of the sigma-1 receptor (S1R) has been shown to attenuate inflammatory stress-mediated brain injuries, and there is emerging evidence that this may involve a BDNF-dependent mechanism. In this report we studied S1R-mediated BDNF release from human astrocytic glial cells. Astrocytes express the S1R, which mediates BDNF release when stimulated with the prototypical S1R agonists 4-PPBP and (+)-SKF10047. This effect could be antagonized by a selective concentration of the S1R antagonist BD1063. Haloperidol is known to have high affinity interactions with the S1R, yet it was unable to facilitate BDNF release. Remarkably, however, two metabolites of haloperidol, haloperidol I and haloperidol II (reduced haloperidol), were discovered to facilitate BDNF secretion and this effect was antagonized by BD1063. Neither 4-PPBP, nor either of the haloperidol metabolites affected the level of BDNF mRNA as assessed by qPCR. These results demonstrate for the first time that haloperidol metabolites I and II facilitate the secretion of BDNF from astrocytes by acting as functionally selective S1R agonists. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Cloning, Identification, and Characterization of the rpoS-Like Sigma Factor rpoX from Vibrio alginolyticus

    Directory of Open Access Journals (Sweden)

    Jing-jing Zhao

    2009-01-01

    Full Text Available Vibrio alginolyticus ZJ-51 displays phase variation between opaque/rugose colonies (Op and translucent/smooth colonies (Tr. These colony variants show great differences in biofilm formation and motility. In this study, a gene encoding for an rpoS-like sigma factor, rpoX, has been cloned and characterized. The absence of rpoX did not affect colony switching rate but did decrease biofilm formation in both the Op and the Tr variants. When challenged with hydrogen peroxide, the ΔrpoX in the Op background showed a slightly higher survival rate compared with the wild type, whereas survival was decreased in the Tr background. Deletion of rpoX in the Tr background resulted in a higher ability to resist ethanol challenges and to survive hyperosmolarity challenges, and in the Op background the opposite phenotype was observed. This indicates that the rpoX gene is involved in biofilm formation and stress response but the effects are controlled by colony phase variation in V. alginolyticus.

  12. Expression of the Arabidopsis Sigma Factor SIG5 Is Photoreceptor and Photosynthesis Controlled

    Directory of Open Access Journals (Sweden)

    Marina Mellenthin

    2014-08-01

    Full Text Available Two collections of Arabidopsis GAL4 enhancer trap lines were screened for light-intensity dependent reporter gene activation. Line N9313 was isolated for its strong light-intensity regulation. The T-DNA element trapped distant enhancers of the SIG5 promoter, which drives expression of a sigma factor involved in regulation of chloroplast genes for photosystem II core proteins. The T-DNA insertion 715 bp upstream of the transcription initiation site splits the promoter in a distal and proximal part. Both parts are sensitive to blue and red light and depend on photosynthetic electron transport activity between photosystem II and the plastoquinone pool. The mainblue-light sensitivity is localized within a 196-bp sequence (–887 to –691 bp in the proximal promoter region It is preferentially CRY1 and PHYB controlled. Type-I and type-II phytochromes mediate red-light sensitivity via various promoter elements spread over the proximal and distal upstream region. This work characterizes SIG5 as an anterograde control factor of chloroplast gene expression, which is controlled by chloroplast signals in a retrograde manner.

  13. Involvement of Clostridium botulinum ATCC 3502 sigma factor K in early-stage sporulation.

    Science.gov (United States)

    Kirk, David G; Dahlsten, Elias; Zhang, Zhen; Korkeala, Hannu; Lindström, Miia

    2012-07-01

    A key survival mechanism of Clostridium botulinum, the notorious neurotoxic food pathogen, is the ability to form heat-resistant spores. While the genetic mechanisms of sporulation are well understood in the model organism Bacillus subtilis, nothing is known about these mechanisms in C. botulinum. Using the ClosTron gene-knockout tool, sigK, encoding late-stage (stage IV) sporulation sigma factor K in B. subtilis, was disrupted in C. botulinum ATCC 3502 to produce two different mutants with distinct insertion sites and orientations. Both mutants were unable to form spores, and their elongated cell morphology suggested that the sporulation pathway was blocked at an early stage. In contrast, sigK-complemented mutants sporulated successfully. Quantitative real-time PCR analysis of sigK in the parent strain revealed expression at the late log growth phase in the parent strain. Analysis of spo0A, encoding the sporulation master switch, in the sigK mutant and the parent showed significantly reduced relative levels of spo0A expression in the sigK mutant compared to the parent strain. Similarly, sigF showed significantly lower relative transcription levels in the sigK mutant than the parent strain, suggesting that the sporulation pathway was blocked in the sigK mutant at an early stage. We conclude that σ(K) is essential for early-stage sporulation in C. botulinum ATCC 3502, rather than being involved in late-stage sporulation, as reported for the sporulation model organism B. subtilis. Understanding the sporulation mechanism of C. botulinum provides keys to control the public health risks that the spores of this dangerous pathogen cause through foods.

  14. Risk factors for stress fractures.

    Science.gov (United States)

    Bennell, K; Matheson, G; Meeuwisse, W; Brukner, P

    1999-08-01

    Preventing stress fractures requires knowledge of the risk factors that predispose to this injury. The aetiology of stress fractures is multifactorial, but methodological limitations and expediency often lead to research study designs that evaluate individual risk factors. Intrinsic risk factors include mechanical factors such as bone density, skeletal alignment and body size and composition, physiological factors such as bone turnover rate, flexibility, and muscular strength and endurance, as well as hormonal and nutritional factors. Extrinsic risk factors include mechanical factors such as surface, footwear and external loading as well as physical training parameters. Psychological traits may also play a role in increasing stress fracture risk. Equally important to these types of analyses of individual risk factors is the integration of information to produce a composite picture of risk. The purpose of this paper is to critically appraise the existing literature by evaluating study design and quality, in order to provide a current synopsis of the known scientific information related to stress fracture risk factors. The literature is not fully complete with well conducted studies on this topic, but a great deal of information has accumulated over the past 20 years. Although stress fractures result from repeated loading, the exact contribution of training factors (volume, intensity, surface) has not been clearly established. From what we do know, menstrual disturbances, caloric restriction, lower bone density, muscle weakness and leg length differences are risk factors for stress fracture. Other time-honoured risk factors such as lower extremity alignment have not been shown to be causative even though anecdotal evidence indicates they are likely to play an important role in stress fracture pathogenesis.

  15. Factors critical to a sustainable deployment of Lean Six Sigma in Australian business.

    OpenAIRE

    Hilton, Roger John

    2017-01-01

    Over the last two decades, manufacturers in Australia have implemented process improvement methodologies to assist in driving down the costs of operations brought on by customers wanting better quality and responsiveness. Closely following in the footsteps of the manufacturers, since the early 2000’s, are service organizations, including those in Healthcare, Finance/Banking, IT and Government (Public sector). Lean Six Sigma is one such process improvement methodology. It is seen as the lat...

  16. Dual-specificity anti-sigma factor reinforces control of cell-type specific gene expression in Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Mónica Serrano

    2015-04-01

    Full Text Available Gene expression during spore development in Bacillus subtilis is controlled by cell type-specific RNA polymerase sigma factors. σFand σE control early stages of development in the forespore and the mother cell, respectively. When, at an intermediate stage in development, the mother cell engulfs the forespore, σF is replaced by σG and σE is replaced by σK. The anti-sigma factor CsfB is produced under the control of σF and binds to and inhibits the auto-regulatory σG, but not σF. A position in region 2.1, occupied by an asparagine in σG and by a glutamate in οF, is sufficient for CsfB discrimination of the two sigmas, and allows it to delay the early to late switch in forespore gene expression. We now show that following engulfment completion, csfB is switched on in the mother cell under the control of σK and that CsfB binds to and inhibits σE but not σK, possibly to facilitate the switch from early to late gene expression. We show that a position in region 2.3 occupied by a conserved asparagine in σE and by a conserved glutamate in σK suffices for discrimination by CsfB. We also show that CsfB prevents activation of σG in the mother cell and the premature σG-dependent activation of σK. Thus, CsfB establishes negative feedback loops that curtail the activity of σE and prevent the ectopic activation of σG in the mother cell. The capacity of CsfB to directly block σE activity may also explain how CsfB plays a role as one of the several mechanisms that prevent σE activation in the forespore. Thus the capacity of CsfB to differentiate between the highly similar σF/σG and σE/σK pairs allows it to rinforce the cell-type specificity of these sigma factors and the transition from early to late development in B. subtilis, and possibly in all sporeformers that encode a CsfB orthologue.

  17. Activation of Sigma-1 receptor ameliorates anxiety-like behavior and cognitive impairments in a rat model of post-traumatic stress disorder.

    Science.gov (United States)

    Ji, Li-Li; Peng, Jun-Bo; Fu, Chang-Hai; Cao, Dong; Li, Dan; Tong, Lei; Wang, Zhen-Yu

    2016-09-15

    Among learning and memory processes, fear memories are crucial in some psychiatric disorders like post-traumatic stress disorder (PTSD). Accumulating evidence shows that the sigma-1 receptor (Sig-1R) has comprehensive involvement in cognitive impairment and neuroprotective effects. It has also been reported that BDNF appears to enhance extinction of fear in anxiety disorders via the MAPK signaling cascade. However, it remains unclear whether BDNF-TrkB-MAPK pathway may be mechanistically involved in the therapeutic effect of sigma-1 receptor in the development of PTSD. To address this question, rats were subjected to a classical single-prolonged stress procedure (SPS) and kept undisturbed for 7 days. After that, rats were re-stressed by re-exposure to the forced swim component of SPS (RSPS). Behavior tests were subsequently performed to assess anxiety and cognitive impairments. Furthermore, we analyzed the expression of BDNF and the phosphorylation of TrkB and three MAPK pathways, namely, the ERK, JNK and p38. We found that the levels of BDNF and p-TrkB were increased following the RSPS procedure, which were reversed by the administration of PRE-084. Meanwhile, among the three MAPK signaling pathways, only the p-ERK expression was increased following the RSPS procedure. Collectively, our results indicate that BDNF-TrkB-ERK signaling pathway may be involved in the activation of sigma-1 receptor to yield therapeutic benefits for PTSD. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Factors affecting the frequency of infection by the sigma virus in experimental populations of Drosophila melanogaster.

    Science.gov (United States)

    Fleuriet, A

    1982-01-01

    The experiments reported in this paper deal with the maintenance of the non contagious, hereditary virus sigma in populations of its host, Drosophila melanogaster. Evidence was previously provided of the existence of two viral Types I and II, depending on their sensitivity to the ref(2)Pp allele (the ref(2)P locus interferes with the multiplication of the virus in the fly). The viral Type I which is the most sensitive to the ref(2)Pp allele, is eliminated in the presence of this allele, even when most of the flies were originally infected in the population. On the contrary, the presence of the ref(2)Pp allele does not prevent a viral Type II, introduced in a population, from infecting most of the flies. The possibility that a change has occurred recently in French natural populations of Drosophila melanogaster is discussed.

  19. 6 sigma quality performance

    International Nuclear Information System (INIS)

    Yu, Yeong Hak

    2000-03-01

    This deals with 6 sigma quality performance introducing company which has 6 sigma quality management, 6 sigma quality activity and customer, secret of success of 6 sigma quality management, what 6 sigma is, 6 sigma quality management propel system 5 propel steps of project like point of 6 sigma, flow of problem solution, tool for propel of project, performance of CTQ and total customer satisfaction, and quality management system and 6 sigma quality.

  20. Sigma-1 receptor chaperones regulate the secretion of brain-derived neurotrophic factor.

    Science.gov (United States)

    Fujimoto, Michiko; Hayashi, Teruo; Urfer, Roman; Mita, Shiro; Su, Tsung-Ping

    2012-07-01

    The sigma-1 receptor (Sig-1R) is a novel endoplasmic reticulum (ER) molecular chaperone that regulates protein folding and degradation. The Sig-1R activation by agonists is known to improve memory, promote cell survival, and exert an antidepressant-like action in animals. Cutamesine (SA4503), a selective Sig-1R ligand, was shown to increase BDNF in the hippocampus of rats. How exactly the intracellular chaperone Sig-1R or associated ligand causes the increase of BDNF or any other neurotrophins is unknown. We examined here whether the action of Sig-1Rs may relate to the post-translational processing and release of BDNF in neuroblastoma cell lines. We used in vitro assays and confirmed that cutamesine possesses the bona fide Sig-1R agonist property by causing the dissociation of BiP from Sig-1Rs. The C-terminus of Sig-1Rs exerted robust chaperone activity by completely blocking the aggregation of BDNF and GDNF in vitro. Chronic treatment with cutamesine in rat B104 neuroblastoma caused a time- and dose-dependent potentiation of the secretion of BDNF without affecting the mRNA level of BDNF. Cutamesine decreased the intracellular level of pro-BDNF and mature BDNF whereas increased the extracellular level of mature BDNF. The pulse-chase experiment indicated that the knockdown of Sig-1Rs decreased the secreted mature BDNF in B104 cells without affecting the synthesis of BDNF. Our findings indicate that, in contrast to clinically used antidepressants that promote the transcriptional upregulation of BDNF, the Sig-1R agonist cutamesine potentiates the post-translational processing of neurotrophins. This unique pharmacological profile may provide a novel therapeutic opportunity for the treatment of neuropsychiatric disorders. Copyright © 2012 Wiley Periodicals, Inc.

  1. Mutations in the Primary Sigma Factor σA and Termination Factor Rho That Reduce Susceptibility to Cell Wall Antibiotics

    Science.gov (United States)

    Lee, Yong Heon

    2014-01-01

    Combinations of glycopeptides and β-lactams exert synergistic antibacterial activity, but the evolutionary mechanisms driving resistance to both antibiotics remain largely unexplored. By repeated subculturing with increasing vancomycin (VAN) and cefuroxime (CEF) concentrations, we isolated an evolved strain of the model bacterium Bacillus subtilis with reduced susceptibility to both antibiotics. Whole-genome sequencing revealed point mutations in genes encoding the major σ factor of RNA polymerase (sigA), a cell shape-determining protein (mreB), and the ρ termination factor (rho). Genetic-reconstruction experiments demonstrated that the G-to-C substitution at position 336 encoded by sigA (sigAG336C), in the domain that recognizes the −35 promoter region, is sufficient to reduce susceptibility to VAN and works cooperatively with the rhoG56C substitution to increase CEF resistance. Transcriptome analyses revealed that the sigAG336C substitution has wide-ranging effects, including elevated expression of the general stress σ factor (σB) regulon, which is required for CEF resistance, and decreased expression of the glpTQ genes, which leads to fosfomycin (FOS) resistance. Our findings suggest that mutations in the core transcriptional machinery may facilitate the evolution of resistance to multiple cell wall antibiotics. PMID:25112476

  2. Processing of cell-surface signalling anti-sigma factors prior to signal recognition is aconserved autoproteolytic mechanism that produces two functional domains.

    NARCIS (Netherlands)

    Bastiaansen, K.C.J.T.; Otero-Asman, J.R.; Luirink, J.; Bitter, W.; Llamas, M.A.

    2015-01-01

    Cell-surface signalling (CSS) enables Gram-negative bacteria to transduce an environmental signal into a cytosolic response. This regulatory cascade involves an outer membrane receptor that transmits the signal to an anti-sigma factor in the cytoplasmic membrane, allowing the activation of an

  3. Factors critical to the success of Six-Sigma quality program and their influence on performance indicators in some of Lebanese hospitals

    Directory of Open Access Journals (Sweden)

    Assrar Sabry

    2014-10-01

    The rest of the paper is organized as follows: First, an overview on the relevant literature reviews with respect to the identified Six-Sigma factors. After that, the methodology and the data analysis of the results are presented. The end of this paper is concluded with the discussion and suggestions for further research.

  4. Expression of alkyl hydroperoxide reductase is regulated negatively by OxyR1 and positively by RpoE2 sigma factor in Azospirillum brasilense Sp7.

    Science.gov (United States)

    Singh, Sudhir; Dwivedi, Susheel Kumar; Singh, Vijay Shankar; Tripathi, Anil Kumar

    2016-10-01

    OxyR proteins are LysR-type transcriptional regulators, which play an important role in responding to oxidative stress in bacteria. Azospirillum brasilense Sp7 harbours two copies of OxyR. The inactivation of the oxyR1, the gene organized divergently to ahpC in A. brasilense Sp7, led to an increased tolerance to alkyl hydroperoxides, which was corroborated by an increase in alkyl hydroperoxide reductase (AhpC) activity, enhanced expression of ahpC :lacZ fusion and increased synthesis of AhpC protein in the oxyR1::km mutant. The upstream region of ahpC promoter harboured a putative OxyR binding site, T-N11-A. Mutation of T, A or both in the T-N11-Amotif caused derepression of ahpC in A. brasilense suggesting that T-N11-A might be the binding site for a negative regulator. Retardation of the electrophoretic mobility of the T-N11-A motif harbouring oxyR1-ahpC intergenic DNA by recombinant OxyR1, under reducing as well as oxidizing conditions, indicated that OxyR1 acts as a negative regulator of ahpC in A. brasilense. Sequence of the promoter of ahpC, predicted on the basis of transcriptional start site, and an enhanced expression of ahpC:lacZ fusion in chrR2::km mutant background suggested that ahpC promoter was RpoE2 dependent. Thus, this study shows that in A. brasilense Sp7, ahpC expression is regulated negatively by OxyR1 but is regulated positively by RpoE2, an oxidative-stress-responsive sigma factor. It also shows that OxyR1 regulates the expression RpoE1, which is known to play an important role during photooxidative stress in A. brasilense.

  5. The point of 6 sigma

    International Nuclear Information System (INIS)

    An, Yeong Jin

    2000-07-01

    This book gives descriptions of the point of 6 sigma. These are the titles of this : what 6 sigma is, sigma conception, motor roller 3.4 ppm, centering error, 6 sigma purpose, 6 sigma principle, eight steps of innovation strategy, 6 sigma innovation strategy of easy system step, measurement standard of 6 sigma outcome, the main role of 6 sigma, acknowledgment and reword, 6 sigma characteristic, 6 sigma effect, 6 sigma application and problems which happen when 6 sigma introduces.

  6. The Extra-Cytoplasmic Function Sigma Factor SigX Modulates Biofilm and Virulence-Related Properties in Pseudomonas aeruginosa

    Science.gov (United States)

    Gicquel, Gwendoline; Bouffartigues, Emeline; Bains, Manjeet; Oxaran, Virginie; Rosay, Thibaut; Lesouhaitier, Olivier; Connil, Nathalie; Bazire, Alexis; Maillot, Olivier; Bénard, Magalie; Cornelis, Pierre; Hancock, Robert E. W.; Dufour, Alain; Feuilloley, Marc G. J.; Orange, Nicole; Déziel, Eric; Chevalier, Sylvie

    2013-01-01

    SigX, one of the 19 extra-cytoplasmic function sigma factors of P. aeruginosa, was only known to be involved in transcription of the gene encoding the major outer membrane protein OprF. We conducted a comparative transcriptomic study between the wildtype H103 strain and its sigX mutant PAOSX, which revealed a total of 307 differentially expressed genes that differed by more than 2 fold. Most dysregulated genes belonged to six functional classes, including the “chaperones and heat shock proteins”, “antibiotic resistance and susceptibility”, “energy metabolism”, “protein secretion/export apparatus”, and “secreted factors”, and “motility and attachment” classes. In this latter class, the large majority of the affected genes were down-regulated in the sigX mutant. In agreement with the array data, the sigX mutant was shown to demonstrate substantially reduced motility, attachment to biotic and abiotic surfaces, and biofilm formation. In addition, virulence towards the nematode Caenorhabditis elegans was reduced in the sigX mutant, suggesting that SigX is involved in virulence-related phenotypes. PMID:24260387

  7. Alternative Sigma Factor HrpL of Pectobacterium carotovorum 35 is Important for the Development of Soft-rot Symptoms

    Directory of Open Access Journals (Sweden)

    Hyo-Song Nam

    2011-08-01

    Full Text Available A bacterial artificial chromosome library of Pectobacterium carotovorum 35 was constructed to characterize the genome and to sequence its hrp region. The hrp cluster of P. carotovorum 35 consisted of 26 open reading frames in five operons. A promoter-based green fluorescent protein technology was used to identify the genes regulated by the alternative sigma factor, HrpL, in P. carotovorum 35. The majority of the selected clones contained the hrpJ operon promoter sequence, which harbors a hrp box, but no putative hrp boxes were detected within the promoter sequences of two other hrpL-regulated genes encoding for pectate lyase and large repetitive protein. Although the promoters of five other hrp operons also contained hrp boxes, their expression was not HrpL-dependent in the promoter-based selection in E. coli. However, transcriptional analysis showed that expression from all operons harboring hrp boxes, except for the hrpN operon, was reduced significantly in the hrpL mutant. The severity of soft-rot symptoms when the hrpL mutant was applied to the surface of tobacco leaves, mimicking natural infection, was greatly attenuated. These results indicate that the hrpL gene of P. carotovorum 35 may be involved in the development of soft-rot symptoms.

  8. Potentiation of nerve growth factor-induced neurite outgrowth in PC12 cells by ifenprodil: the role of sigma-1 and IP3 receptors.

    Directory of Open Access Journals (Sweden)

    Tamaki Ishima

    Full Text Available In addition to both the α1 adrenergic receptor and N-methyl-D-aspartate (NMDA receptor antagonists, ifenprodil binds to the sigma receptor subtypes 1 and 2. In this study, we examined the effects of ifenprodil on nerve growth factor (NGF-induced neurite outgrowth in PC12 cells. Ifenprodil significantly potentiated NGF-induced neurite outgrowth, in a concentration-dependent manner. In contrast, the α1 adrenergic receptor antagonist, prazosin and the NMDA receptor NR2B antagonist, Ro 25-6981 did not alter NGF-induced neurite outgrowth. Potentiation of NGF-induced neurite outgrowth mediated by ifenprodil was significantly antagonized by co-administration of the selective sigma-1 receptor antagonist, NE-100, but not the sigma-2 receptor antagonist, SM-21. Similarly, ifenprodil enhanced NGF-induced neurite outgrowth was again significantly reduced by the inositol 1,4,5-triphosphate (IP(3 receptor antagonists, xestospongin C and 2-aminoethoxydiphenyl borate (2-APB treatment. Furthermore, BAPTA-AM, a chelator of intracellular Ca(2+, blocked the effects of ifenprodil on NGF-induced neurite outgrowth, indicating the role of intracellular Ca(2+ in the neurite outgrowth. These findings suggest that activation at sigma-1 receptors and subsequent interaction with IP(3 receptors may mediate the pharmacological effects of ifenprodil on neurite outgrowth.

  9. Sigma Factor SigB Is Crucial to Mediate Staphylococcus aureus Adaptation during Chronic Infections.

    Directory of Open Access Journals (Sweden)

    Lorena Tuchscherr

    2015-04-01

    Full Text Available Staphylococcus aureus is a major human pathogen that causes a range of infections from acute invasive to chronic and difficult-to-treat. Infection strategies associated with persisting S. aureus infections are bacterial host cell invasion and the bacterial ability to dynamically change phenotypes from the aggressive wild-type to small colony variants (SCVs, which are adapted for intracellular long-term persistence. The underlying mechanisms of the bacterial switching and adaptation mechanisms appear to be very dynamic, but are largely unknown. Here, we analyzed the role and the crosstalk of the global S. aureus regulators agr, sarA and SigB by generating single, double and triple mutants, and testing them with proteome analysis and in different in vitro and in vivo infection models. We were able to demonstrate that SigB is the crucial factor for adaptation in chronic infections. During acute infection, the bacteria require the simultaneous action of the agr and sarA loci to defend against invading immune cells by causing inflammation and cytotoxicity and to escape from phagosomes in their host cells that enable them to settle an infection at high bacterial density. To persist intracellularly the bacteria subsequently need to silence agr and sarA. Indeed agr and sarA deletion mutants expressed a much lower number of virulence factors and could persist at high numbers intracellularly. SigB plays a crucial function to promote bacterial intracellular persistence. In fact, ΔsigB-mutants did not generate SCVs and were completely cleared by the host cells within a few days. In this study we identified SigB as an essential factor that enables the bacteria to switch from the highly aggressive phenotype that settles an acute infection to a silent SCV-phenotype that allows for long-term intracellular persistence. Consequently, the SigB-operon represents a possible target to develop preventive and therapeutic strategies against chronic and therapy

  10. Sigma Factor SigB Is Crucial to Mediate Staphylococcus aureus Adaptation during Chronic Infections.

    Science.gov (United States)

    Tuchscherr, Lorena; Bischoff, Markus; Lattar, Santiago M; Noto Llana, Mariangeles; Pförtner, Henrike; Niemann, Silke; Geraci, Jennifer; Van de Vyver, Hélène; Fraunholz, Martin J; Cheung, Ambrose L; Herrmann, Mathias; Völker, Uwe; Sordelli, Daniel O; Peters, Georg; Löffler, Bettina

    2015-04-01

    Staphylococcus aureus is a major human pathogen that causes a range of infections from acute invasive to chronic and difficult-to-treat. Infection strategies associated with persisting S. aureus infections are bacterial host cell invasion and the bacterial ability to dynamically change phenotypes from the aggressive wild-type to small colony variants (SCVs), which are adapted for intracellular long-term persistence. The underlying mechanisms of the bacterial switching and adaptation mechanisms appear to be very dynamic, but are largely unknown. Here, we analyzed the role and the crosstalk of the global S. aureus regulators agr, sarA and SigB by generating single, double and triple mutants, and testing them with proteome analysis and in different in vitro and in vivo infection models. We were able to demonstrate that SigB is the crucial factor for adaptation in chronic infections. During acute infection, the bacteria require the simultaneous action of the agr and sarA loci to defend against invading immune cells by causing inflammation and cytotoxicity and to escape from phagosomes in their host cells that enable them to settle an infection at high bacterial density. To persist intracellularly the bacteria subsequently need to silence agr and sarA. Indeed agr and sarA deletion mutants expressed a much lower number of virulence factors and could persist at high numbers intracellularly. SigB plays a crucial function to promote bacterial intracellular persistence. In fact, ΔsigB-mutants did not generate SCVs and were completely cleared by the host cells within a few days. In this study we identified SigB as an essential factor that enables the bacteria to switch from the highly aggressive phenotype that settles an acute infection to a silent SCV-phenotype that allows for long-term intracellular persistence. Consequently, the SigB-operon represents a possible target to develop preventive and therapeutic strategies against chronic and therapy-refractory infections.

  11. Sigma-1 receptor mediates cocaine-induced transcriptional regulation by recruiting chromatin-remodeling factors at the nuclear envelope.

    Science.gov (United States)

    Tsai, Shang-Yi A; Chuang, Jian-Ying; Tsai, Meng-Shan; Wang, Xiao-Fei; Xi, Zheng-Xiong; Hung, Jan-Jong; Chang, Wen-Chang; Bonci, Antonello; Su, Tsung-Ping

    2015-11-24

    The sigma-1 receptor (Sig-1R) chaperone at the endoplasmic reticulum (ER) plays important roles in cellular regulation. Here we found a new function of Sig-1R, in that it translocates from the ER to the nuclear envelope (NE) to recruit chromatin-remodeling molecules and regulate the gene transcription thereof. Sig-1Rs mainly reside at the ER-mitochondrion interface. However, on stimulation by agonists such as cocaine, Sig-1Rs translocate from ER to the NE, where Sig-1Rs bind NE protein emerin and recruit chromatin-remodeling molecules, including lamin A/C, barrier-to-autointegration factor (BAF), and histone deacetylase (HDAC), to form a complex with the gene repressor specific protein 3 (Sp3). Knockdown of Sig-1Rs attenuates the complex formation. Cocaine was found to suppress the gene expression of monoamine oxidase B (MAOB) in the brain of wild-type but not Sig-1R knockout mouse. A single dose of cocaine (20 mg/kg) in rats suppresses the level of MAOB at nuclear accumbens without affecting the level of dopamine transporter. Daily injections of cocaine in rats caused behavioral sensitization. Withdrawal from cocaine in cocaine-sensitized rats induced an apparent time-dependent rebound of the MAOB protein level to about 200% over control on day 14 after withdrawal. Treatment of cocaine-withdrawn rats with the MAOB inhibitor deprenyl completely alleviated the behavioral sensitization to cocaine. Our results demonstrate a role of Sig-1R in transcriptional regulation and suggest cocaine may work through this newly discovered genomic action to achieve its addictive action. Results also suggest the MAOB inhibitor deprenyl as a therapeutic agent to block certain actions of cocaine during withdrawal.

  12. The six sigma program: an empirical study of brazilian companies.

    OpenAIRE

    Carvalho, Marly Monteiro de; Ho, Linda Lee; Pinto, Silvia Helena Boarin

    2014-01-01

    Purpose – The purpose of this paper is to assess the status of Six Sigma's status in Brazilian companies and understand the integration of this program with other quality management approaches. Additionally, the critical success factors (CSFs) for Six Sigma implementation and primary Six Sigma program characteristics were identified. Finally, the results of the used of Six Sigma were analysed. Design/methodology/approach – An extensive literature review illustrates the primary Six Sigma c...

  13. NMR studies of the sporulation protein SpoIIAA: Implications for the regulation of the transcription factor {sigma}F in Bacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, Helena; Comfort, David; Lord, Matthew; Yudkin, Michael; Campbell, Iain D.; Nilges, Michael

    2001-04-15

    SpoIIAA participates in a four-component mechanism for phosphorylation-dependent transcription control at the outset of sporulation. We report the refinement of the solution structure of SpoIIAA by using the automated iterative NOE assignment method ARIA. To complement the structural data, the protein dynamics were determined by measuring the T{sub 1}, T{sub 2} and NOE of the backbone {sup 15}N-nuclei. The refined structure permits a discussion of the structural features that are important for the function of SpoIIAA in the regulation of the sporulation sigma factor {sigma}{sup F}, and for homologous regulatory pathways present in B. subtilis and in other bacilli.

  14. Responsibility Factors of Reducing Inefficiencies in Information System Processes and Their Role on Intention to Acquire Six Sigma Certification

    Science.gov (United States)

    Hejazi, Sara

    2009-01-01

    Organizations worldwide have been turning to Six Sigma program (SSP) to eliminate the defects in their products or drive out the variability in their processes to attain a competitive advantage in their marketplace. An effective certification program has been touted as a major contributor to successful implementation of SSP. An effective…

  15. Involvement of the Mannose Phosphotransferase System of Lactobacillus plantarum WCFS1 in Peroxide Stress Tolerance

    NARCIS (Netherlands)

    Stevens, Marc J. A.; Molenaar, Douwe; de Jong, Anne; de Vos, Willem M.; Kleerebezem, Michiel

    A Lactobacillus plantarum strain with a deletion in the gene rpoN, encoding the alternative sigma factor 54 (sigma(54)), displayed a 100-fold-higher sensitivity to peroxide than its parental strain. This feature could be due to sigma(54)-dependent regulation of genes involved in the peroxide stress

  16. Alternative Sigma Factors SigF, SigE, and SigG Are Essential for Sporulation in Clostridium botulinum ATCC 3502

    OpenAIRE

    Kirk, David G.; Zhang, Zhen; Korkeala, Hannu; Lindström, Miia

    2014-01-01

    Clostridium botulinum produces heat-resistant endospores that may germinate and outgrow into neurotoxic cultures in foods. Sporulation is regulated by the transcription factor Spo0A and the alternative sigma factors SigF, SigE, SigG, and SigK in most spore formers studied to date. We constructed mutants of sigF, sigE, and sigG in C. botulinum ATCC 3502 and used quantitative reverse transcriptase PCR and electron microscopy to assess their expression of the sporulation pathway on transcription...

  17. Stress Concentration Factor and Stress Intensity Factor with U-notch and Crack in the Beam

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Bo Seong; Lee, Kwang Ho [Kyungpook National Univ., Daegu (Korea, Republic of)

    2016-05-15

    The stress concentration factors and stress intensity factors for a simple beam and a cantilever are analyzed by using finite element method and photoelasticity. Using the analyzed results, the estimated graphs on stress concentration factors and stress intensity factors are obtained. To analyze stress concentration factors of notch, the dimensionless notch length H(height of specimen)/h=1.1-2 and dimensionless gap space r(radius at the notch tip)/h=0.1~0.5 are used, where h=H-c and c is the notch length. As the notch gap length increases and the gap decreases, the stress concentration factors increase. Stress concentration factors of a simple beam are greater than those of a cantilever beam. However, actually, the maximum stress values under a load, a notch length and a gap occur more greatly in the cantilever beam than in the simple beam. To analyze stress intensity factors, the normalized crack length α(crack length)/H=0.2~0.5 is used. As the length of the crack increases, the normalized stress intensity factors increase. The stress intensity factors under a constant load and a crack length occur more greatly in the cantilever beam than in the simple beam.

  18. Identification of the sigmaB regulon of Bacillus cereus and conservation of sigmaB-regulated genes in low-GC-content gram-positive bacteria

    NARCIS (Netherlands)

    Schaik, van W.; Voort, van der M.; Molenaar, D.; Moezelaar, R.; Vos, de W.M.; Abee, T.

    2007-01-01

    The alternative sigma factor B has an important role in the acquisition of stress resistance in many gram-positive bacteria, including the food-borne pathogen Bacillus cereus. Here, we describe the identification of the set of B-regulated genes in B. cereus by DNA microarray analysis of the

  19. Topological massive sigma models

    International Nuclear Information System (INIS)

    Lambert, N.D.

    1995-01-01

    In this paper we construct topological sigma models which include a potential and are related to twisted massive supersymmetric sigma models. Contrary to a previous construction these models have no central charge and do not require the manifold to admit a Killing vector. We use the topological massive sigma model constructed here to simplify the calculation of the observables. Lastly it is noted that this model can be viewed as interpolating between topological massless sigma models and topological Landau-Ginzburg models. ((orig.))

  20. Stress concentration factor and stress intensity factor on hard metals in connection with the wear characteristics

    International Nuclear Information System (INIS)

    Dawihl, W.; Altmeyer, G.

    1977-01-01

    Description of a method to determine stress intensity factors on hard metals by lapping in notches of different diameter. Dependence of the values of the stress intensity factors on the size of the notch base diameter. For tungsten carbide hard metals with 6% Co, determination of a final value of 250 Nmm -3 / 2 . Characterisation of the stress intensity factor governed by the surface roughness which is decisive for the assessment of the wear-resistant behaviour. (orig.) [de

  1. NUR TRANSCRIPTION FACTORS IN STRESS AND ADDICTION

    Directory of Open Access Journals (Sweden)

    Danae eCampos-Melo

    2013-12-01

    Full Text Available The Nur transcription factors Nur77 (NGFI-B, NR4A1, Nurr1 (NR4A2 and Nor-1 (NR4A3 are a sub-family of orphan members of the nuclear receptor superfamily. These transcription factors are products of immediate early genes, whose expression is rapidly and transiently induced in the central nervous system by several types of stimuli. Nur factors are present throughout the hypothalamus-pituitary-adrenal axis where are prominently induced in response to stress. Drugs of abuse and stress also induce the expression of Nur factors in nuclei of the motivation/reward circuit of the brain, indicating their participation in the process of drug addiction and in non-hypothalamic responses to stress. Repeated use of addictive drugs and chronic stress induce long-lasting dysregulation of the brain motivation/reward circuit, due to reprogramming of gene expression and enduring alterations in neuronal function. Here, we review the data supporting that Nur transcription factors are key players in the molecular basis of the dysregulation of neuronal circuits involved in chronic stress and addiction.

  2. Stress intensity factors and constant stress terms for interface cracks

    International Nuclear Information System (INIS)

    Fett, T.; Rizzi, G.

    2004-01-01

    In bi-material joints cracks can propagate along the interface or kink into one of the two materials. Whereas the energy release rate can be applied for interface cracks in the same way as usual for homogeneous materials, the computation of stresses in the vicinity of the crack tip is significantly more complicated. In order to assess crack kinking, it is necessary to know the mixed-mode stress intensity factor contributions K I and K II as well as the constant stress terms in the two materials. Whereas the stress intensity factors are available for a large number of infinite and semi-infinite bodies, there is experimental interest in practically used test specimens. This especially holds for the constant x-stress terms. Finite element computations are performed for the special case of a disappearing second Dundurs parameter, i.e. β=0. The fracture mechanics parameters K I , K II , σ 0 for the interface crack are reported in the form of diagrams and approximate relations. (orig.)

  3. PREDICTION OF STRESS CONCENTRATION FACTORS IN

    African Journals Online (AJOL)

    ES OBE

    consider the effect of brace spacing on strengths of tubular K joints without consideration of same effect on square section K Joints. This lack of studies design strengths of gapped square section K joints makes availability of information on stress concentration factors in same joints scarce. However, information on 'Hot Spot' ...

  4. SIX SIGMA: A LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    S.A. Oke

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: Despite stiff international competition in the global market, world-class manufacturers are increasing their market share and profits through low-cost production, waste reduction in manufacturing, production of high quality products, and exceptional customer service. Six Sigma has been successfully implemented in this regard. In this paper, a selected survey of Six Sigma literature is presented to illustrate the wide scope of the application of the concept. This could be of immense benefit to organizations’ top management who need to understand the critical variables and factors for the successful implementation of Six Sigma programmes, leading to substantial, sustainable long-term improvement in performance results, value for money, and effort. The paper presents motivated pointers – substantiated as far as possible by data and evidence – to key success factors, variables, and their interrelationships.

    AFRIKAANSE OPSOMMING: Sterk internasionale mededinging ten spyt verhoog wêreldklasvervaardigers hul markaandeel en winste via laekosteproduksie, skrootvermindering, die produksie van gehalteprodukte en die lewering van primadiens aan klante. Ses Sigma is in hierdie verband as gereedskap suksesvol geïmplimenteer. Die artikel behandel 'n gekeurde oorsig van Ses Sigmaliteratuur om sodoende die toepassingsveldwyde van die konsep te illustreer. Die artikel is nuttig vir organisasiebestuurders uit die oogpunt van veranderlikes en suksesfaktore wat deur die Ses Sigmametode tot substansiële en volhoubare langtermyn verbeterings van 'n onderneming kan lei.

  5. SIGMA without effort

    International Nuclear Information System (INIS)

    Hagedorn, R.; Reinfelds, J.

    1978-01-01

    SIGMA (System for Interactive Graphical Analysis) is an interactive computing language with automatic array handling and graphical facilities. It is designed as a tool for mathematical problem solving. The SIGMA language is simple, almost obvious, yet flexible and powerful. This tutorial introduces the beginner to SIGMA. It is supposed to be used at a graphics terminal having access to SIGMA. The user will learn the language in dialogue with the system in sixteen sessions of about one hour. The first session enables him already to compute and display functions of one or two variables. (Auth.)

  6. Six Sigma software development

    CERN Document Server

    Tayntor, Christine B

    2002-01-01

    Since Six Sigma has had marked success in improving quality in other settings, and since the quality of software remains poor, it seems a natural evolution to apply the concepts and tools of Six Sigma to system development and the IT department. Until now however, there were no books available that applied these concepts to the system development process. Six Sigma Software Development fills this void and illustrates how Six Sigma concepts can be applied to all aspects of the evolving system development process. It includes the traditional waterfall model and in the support of legacy systems,

  7. Workplace Stress, Organizational Factors and EAP Utilization.

    Science.gov (United States)

    Azzone, Vanessa; McCann, Bernard; Merrick, Elizabeth Levy; Hiatt, Deirdre; Hodgkin, Dominic; Horgan, Constance

    2009-01-01

    This study examined relationships between workplace stress, organizational factors and use of EAP counseling services delivered by network providers in a large, privately-insured population. Claims data were linked to measures of workplace stress, focus on wellness/prevention, EAP promotion, and EAP activities for health care plan enrollees from 26 employers. The association of external environment and work organization variables with use of EAP counseling services was examined. Higher levels of EAP promotion and worksite activities were associated with greater likelihood of service use. Greater focus on wellness/prevention and unusual and significant stress were associated with lower likelihood of service use. Results provide stakeholders with insights on approaches to increasing utilization of EAP services.

  8. Six Sigma in Education

    Science.gov (United States)

    LeMahieu, Paul G.; Nordstrum, Lee E.; Cudney, Elizabeth A.

    2017-01-01

    Purpose: This paper is one of seven in this volume that aims to elaborate different approaches to quality improvement in education. It delineates a methodology called Six Sigma. Design/methodology/approach: The paper presents the origins, theoretical foundations, core principles and a case study demonstrating an application of Six Sigma in a…

  9. Manage your human sigma.

    Science.gov (United States)

    Fleming, John H; Coffman, Curt; Harter, James K

    2005-01-01

    If sales and service organizations are to improve, they must learn to measure and manage the quality of the employee-customer encounter. Quality improvement methodologies such as Six Sigma are extremely useful in manufacturing contexts, but they're less useful when it comes to human interactions. To address this problem, the authors have developed a quality improvement approach they refer to as Human Sigma. It weaves together a consistent method for assessing the employee-customer encounter and a disciplined process for managing and improving it. There are several core principles for measuring and managing the employee-customer encounter: It's important not to think like an economist or an engineer when assessing interactions because emotions inform both sides' judgments and behavior. The employee-customer encounter must be measured and managed locally, because there are enormous variations in quality at the work-group and individual levels. And to improve the quality of the employee-customer interaction, organizations must conduct both short-term, transactional interventions and long-term, transformational ones. Employee engagement and customer engagement are intimately connected--and, taken together, they have an outsized effect on financial performance. They therefore need to be managed holistically. That is, the responsibility for measuring and monitoring the health of employee-customer relationships must reside within a single organizational structure, with an executive champion who has the authority to initiate and manage change. Nevertheless, the local manager remains the single most important factor in local group performance. A local manager whose work group shows suboptimal performance should be encouraged to conduct interventions, such as targeted training, performance reviews, action learning, and individual coaching.

  10. Narrow Sigma -hypernuclear states

    CERN Document Server

    Gal, A

    1980-01-01

    It is shown that the spin-isospin dependence of low-energy Sigma N to Lambda N conversion leads to substantial quenching of nuclear-matter estimates of the widths of some Sigma -hypernuclear states produced in (K/sup -/, pi ) reactions, to a level below 10 MeV. The estimated widths compare favorably with those of the Sigma -hypernuclear peaks recently observed at CERN for /sup 7/Li, /sup 9/Be, and /sup 12/C. Tentative quantum number assignments are suggested for these states. (10 refs).

  11. Exploring the Factors Contributing to Stress and Coping Strategies ...

    African Journals Online (AJOL)

    Exploring the Factors Contributing to Stress and Coping Strategies of Nurses at ... explore the factors contributing to nurses' stress and related coping strategies used ... of staff and materials, facing death and dying, dissatisfaction with the work ...

  12. Supersymmetric sigma models

    International Nuclear Information System (INIS)

    Bagger, J.A.

    1984-09-01

    We begin to construct the most general supersymmetric Lagrangians in one, two and four dimensions. We find that the matter couplings have a natural interpretation in the language of the nonlinear sigma model

  13. Supersymmetric sigma models

    Energy Technology Data Exchange (ETDEWEB)

    Bagger, J.A.

    1984-09-01

    We begin to construct the most general supersymmetric Lagrangians in one, two and four dimensions. We find that the matter couplings have a natural interpretation in the language of the nonlinear sigma model.

  14. SIGMA Experimental Facility; Facilidad Experimental SIGMA

    Energy Technology Data Exchange (ETDEWEB)

    Rivarola, Martin; Florido, Pablo; Gonzalez, Jose; Brasnarof, Daniel; Orellano, Pablo; Bergallo, Juan [Comision Nacional de Energia Atomica, Centro Atomico Bariloche, Grupo de Disenos Avanzados y Evaluacion Economica, Complejo Tecnologico Pilcaniyeu (Argentina)

    2000-07-01

    The SIGMA ( Separacion Isotopica Gaseosa por Metodos Avanzados) concept is outlined.The old gaseous diffusion process to enrich uranium has been updated to be economically competitive for small production volumes.Major innovations have been introduced in the membrane design and in the integrated design of compressors and diffusers.The use of injectors and gas turbines has been also adopted.The paper describes the demonstration facility installed by the Argentine Atomic Energy Commission.

  15. 6 Sigma project advance

    International Nuclear Information System (INIS)

    2002-12-01

    This book deals with 6 sigma project advance which introduces 6 sigma project in Changwon special steel, how is failure accepted? CTQ selection which is starting line, definition of performance standard, measurement system check on reliability of measurement data, check of process capacity for current level, establishment of target, optimal design and performance of application, practice of management system for maintain of improved result, CTQ selection, check of measurement system and practice of management system.

  16. Factor analysis for exercise stress radionuclide ventriculography

    International Nuclear Information System (INIS)

    Hirota, Kazuyoshi; Yasuda, Mitsutaka; Oku, Hisao; Ikuno, Yoshiyasu; Takeuchi, Kazuhide; Takeda, Tadanao; Ochi, Hironobu

    1987-01-01

    Using factor analysis, a new image processing in exercise stress radionuclide ventriculography, changes in factors associated with exercise were evaluated in 14 patients with angina pectoris or old myocardial infarction. The patients were imaged in the left anterior oblique projection, and three factor images were presented on a color coded scale. Abnormal factors (AF) were observed in 6 patients before exercise, 13 during exercise, and 4 after exercise. In 7 patients, the occurrence of AF was associated with exercise. Five of them became free from AF after exercise. Three patients showing AF before exercise had aggravation of AF during exercise. Overall, the occurrence or aggravation of AF was associated with exercise in ten (71 %) of the patients. The other three patients, however, had disappearance of AF during exercise. In the last patient, none of the AF was observed throughout the study. In view of a high incidence of AF associated with exercise, the factor analysis may have the potential in evaluating cardiac reverse from the viewpoint of left ventricular wall motion abnormality. (Namekawa, K.)

  17. The extracytoplasmic function sigma factor SigY is important for efficient maintenance of the Spβ prophage that encodes sublancin in Bacillus subtilis.

    Science.gov (United States)

    Mendez, Rebecca; Gutierrez, Alba; Reyes, Jasmin; Márquez-Magaña, Leticia

    2012-06-01

    Many strains of the soil bacterium Bacillus subtilis are capable of producing and being resistant to the antibiotic sublancin because they harbor the Spβ prophage. This 135 kb viral genome is integrated into the circular DNA chromosome of B. subtilis, and contains genes for the production of and resistance to sublancin. We investigated the role of SigY in sublancin production and resistance, finding that it is important for efficient maintenance of the Spβ prophage. We were unable to detect the prophage in mutants lacking SigY. Additionally, these mutants were no longer able to produce sublancin, were sensitive to killing by this factor, and displayed a delay in sporulation. Wild-type cells with normal SigY activity were found to partially lose the Spβ prophage during growth and early sporulation, suggesting a mechanism for the bistable outcome of sibling cells capable of killing and of being killed. The appropriate regulation of SigY appears to be essential for growth as evidenced by the inability to disrupt the gene for its putative antisigma. Our results confirm a role for SigY in antibiotic production and resistance, as has been found for other members of the extracytoplasmic function sigma factor family in B. subtilis, and shows that this role is achieved by affecting maintenance of the Spβ prophage.

  18. IDENTIFICATION AND SELECTION OF SIX SIGMA PROJECTS

    Directory of Open Access Journals (Sweden)

    Abdalhkeim FA. Flifel

    2017-04-01

    Full Text Available Six Sigma is a well-structured and proven methodology for improving organizational performance. It helps achieving the goals of the organization through the use of project-driven approach. The implementation of Six sigma approach depends on proper identification and selection of projects, moreover, the selection of right Six sigma projects is one of the critical success factors of six sigma efforts. The paper provides the sources for the identification of potential projects, top down and bottom up approaches, the process of selection of projects, guidelines that assist the selection of appropriate projects, selection criteria which must be precisely chosen in accordance with the objectives, needs and capabilities of the organization as well as sophisticated techniques and tools recommended in the literature for the selection of projects.

  19. Factors causing stress among Pakistani working women

    Directory of Open Access Journals (Sweden)

    Ahmed Arif

    2017-09-01

    Full Text Available Women are traditionally considered to be confined within the four walls of their houses in the developing countries. They are still unable to play an active role in the development of society. They are striving to make their identity as an integral part of the society. Being a member of conservative developing society, women are still facing many hindrances, causing stressful situation for them, which prohibits them to participate actively in the economic development. This paper attempts to explore the critical factors creating stress among Pakistani working women. Based on literature review, the key stressors were identified to be as work life balance, gender discrimination, peers behaviour, lack of promotional opportunities and sexual harassment. These factors were found to be creating physiological, behavioural and psychological problems. The target of this study was the women working in secretarial and administrative positions in Pakistani organisations. Regression analysis was conducted to find out the impact of these stressors on working women. The results revealed that sexual harassment, peers behaviour and lack of promotional opportunities were the most dominant stressors.

  20. σK of Clostridium acetobutylicum is the first known sporulation-specific sigma factor with two developmentally separated roles, one early and one late in sporulation.

    Science.gov (United States)

    Al-Hinai, Mohab A; Jones, Shawn W; Papoutsakis, Eleftherios T

    2014-01-01

    Sporulation in the model endospore-forming organism Bacillus subtilis proceeds via the sequential and stage-specific activation of the sporulation-specific sigma factors, σ(H) (early), σ(F), σ(E), σ(G), and σ(K) (late). Here we show that the Clostridium acetobutylicum σ(K) acts both early, prior to Spo0A expression, and late, past σ(G) activation, thus departing from the B. subtilis model. The C. acetobutylicum sigK deletion (ΔsigK) mutant was unable to sporulate, and solventogenesis, the characteristic stationary-phase phenomenon for this organism, was severely diminished. Transmission electron microscopy demonstrated that the ΔsigK mutant does not develop an asymmetric septum and produces no granulose. Complementation of sigK restored sporulation and solventogenesis to wild-type levels. Spo0A and σ(G) proteins were not detectable by Western analysis, while σ(F) protein levels were significantly reduced in the ΔsigK mutant. spo0A, sigF, sigE, sigG, spoIIE, and adhE1 transcript levels were all downregulated in the ΔsigK mutant, while those of the sigH transcript were unaffected during the exponential and transitional phases of culture. These data show that σ(K) is necessary for sporulation prior to spo0A expression. Plasmid-based expression of spo0A in the ΔsigK mutant from a nonnative promoter restored solventogenesis and the production of Spo0A, σ(F), σ(E), and σ(G), but not sporulation, which was blocked past the σ(G) stage of development, thus demonstrating that σ(K) is also necessary in late sporulation. sigK is expressed very early at low levels in exponential phase but is strongly upregulated during the middle to late stationary phase. This is the first sporulation-specific sigma factor shown to have two developmentally separated roles.

  1. YALIN ALTI SİGMA PROJELERİ İÇİN KRİTİK BAŞARI FAKTÖRLERİ (SUCCESS FACTORS FOR LEAN SIX SIGMA PROJECTS

    Directory of Open Access Journals (Sweden)

    Ali Rıza FİRUZAN

    2012-10-01

    Full Text Available Nowadays many companies focus on various kinds of quality improvement techniques to carry the service quality beyond costumer expectations. The selected quality technique should be appropriate to the company's culture and should be sufficient for carry out targeted improvement; this will enhance the company’s superiority in market place.For this purpose, Lean Six Sigma methods are one of the important methods being used today as an intensive use of statistical tools and techniques. Lean Six Sigma methods can be implemented in almost all sectors and successful gains can be obtained. Lean Six Sigma has wide range application in the world. Most applications are successful, while some of them are failed. In this study, reasons for unsuccessful Lean Six Sigma projects are examined. The way to convert unsuccessful project into successful project are suggested. Some solutions are carried out for this purpose.

  2. Use of In Vitro Transcription System for Analysis of Corynebacterium glutamicum Promoters Recognized by Two Sigma Factors

    Czech Academy of Sciences Publication Activity Database

    Šilar, Radoslav; Holátko, Jiří; Rucká, Lenka; Rapoport, Andrey; Dostálová, Hana; Kadeřábková, Pavla; Nešvera, Jan; Pátek, Miroslav

    2016-01-01

    Roč. 73, č. 3 (2016), s. 401-408 ISSN 0343-8651 Institutional support: RVO:61388971 Keywords : GENE-EXPRESSION * REGULATORY NETWORK * BACILLUS-SUBTILIS Subject RIV: EE - Microbiology , Virology Impact factor: 1.322, year: 2016

  3. Rational selection and engineering of exogenous principal sigma factor (σ(HrdB)) to increase teicoplanin production in an industrial strain of Actinoplanes teichomyceticus.

    Science.gov (United States)

    Wang, Haiyong; Yang, Liu; Wu, Kuo; Li, Guanghui

    2014-01-16

    Transcriptional engineering has presented a strong ability of phenotypic improvement in microorganisms. However, it could not be directly applied to Actinoplanes teichomyceticus L-27 because of the paucity of endogenous transcription factors in the strain. In this study, exogenous transcription factors were rationally selected and transcriptional engineering was carried out to increase the productivity of teicoplanin in L-27. It was illuminated that the σ(HrdB) molecules shared strong similarity of amino acid sequences among some genera of actinomycetes. Combining this advantage with the ability of transcriptional engineering, exogenous sigma factor σ(HrdB) molecules were rationally selected and engineered to improve L-27. hrdB genes from Actinoplanes missouriensis 431, Micromonospora aurantiaca ATCC 27029 and Salinispora arenicola CNS-205 were selected based on molecular evolutionary analysis. Random mutagenesis, DNA shuffling and point mutation were subsequently performed to generate diversified mutants. A recombinant was identified through screening program, yielding 5.3 mg/ml of teicoplanin, over 2-fold compared to that of L-27. More significantly, the engineered strain presented a good performance in 500-l pilot scale fermentation, which meant its valuable potential application in industry. Through rational selection and engineering of exogenous transcriptional factor, we have extended the application of transcriptional engineering. To our knowledge, it is the first time to focus on the related issue. In addition, possessing the advantage of efficient metabolic perturbation in transcription level, this strategy could be useful in analyzing metabolic and physiological mechanisms of strains, especially those with the only information on taxonomy.

  4. Menopause as risk factor for oxidative stress.

    Science.gov (United States)

    Sánchez-Rodríguez, Martha A; Zacarías-Flores, Mariano; Arronte-Rosales, Alicia; Correa-Muñoz, Elsa; Mendoza-Núñez, Víctor Manuel

    2012-03-01

    The aim of this study was to determine the influence of menopause (hypoestrogenism) as a risk factor for oxidative stress. We carried out a cross-sectional study with 187 perimenopausal women from Mexico City, including 94 premenopausal (mean ± SD age, 44.9 ± 4.0 y; estrogen, 95.8 ± 65.7 pg/mL; follicle-stimulating hormone, 13.6 ± 16.9 mIU/mL) and 93 postmenopausal (mean ± SD age, 52.5 ± 3.3 y; estrogen, 12.8 ± 6.8 pg/mL; follicle-stimulating hormone, 51.4 ± 26.9 mIU/mL) women. We measured lipoperoxides using a thiobarbituric acid-reacting substance assay, erythrocyte superoxide dismutase and glutathione peroxidase activities, and the total antioxidant status with the Randox kit. An alternative cutoff value for lipoperoxide level of 0.320 μmol/L or higher was defined on the basis of the 90th percentile of young healthy participants. All women answered the Menopause Rating Scale, the Athens Insomnia Scale, and a structured questionnaire about pro-oxidant factors, that is, smoking, consumption of caffeinated and alcoholic beverages, and physical activity. Finally, we measured weight and height and calculated body mass index. The lipoperoxide levels were significantly higher in the postmenopausal group than in the premenopausal group (0.357 ± 0.05 vs 0.331 ± 0.05 μmol/L, P = 0.001). Using logistic regression to control pro-oxidant variables, we found that menopause was the main risk factor for oxidative stress (odds ratio, 2.62; 95% CI, 1.35-5.11; P menopause rating score, insomnia score, and lipoperoxides, and this relationship was most evident in the postmenopausal group (menopause scale, r = 0.327 [P = 0.001]; insomnia scale, r = 0.209 [P < 0.05]). Our findings suggest that the depletion of estrogen in postmenopause could cause oxidative stress in addition to the known symptoms.

  5. Inference of sigma factor controlled networks by using numerical modeling applied to microarray time series data of the germinating prokaryote

    Czech Academy of Sciences Publication Activity Database

    Straková, Eva; Ziková, Alice; Vohradský, Jiří

    2014-01-01

    Roč. 42, č. 2 (2014), s. 748-763 ISSN 0305-1048 R&D Projects: GA ČR GAP302/11/0229 Institutional support: RVO:61388971 Keywords : STREPTOMYCES-COELICOLOR A3(2) * SMALL NONCODING RNAS * GENE-EXPRESSION Subject RIV: CE - Biochemistry Impact factor: 9.112, year: 2014

  6. The stationary phase sigma factor, RpoS, regulates the production of a carbapenem antibiotic, a bioactive prodigiosin and virulence in the enterobacterial pathogen Serratia sp. ATCC 39006.

    Science.gov (United States)

    Wilf, Nabil M; Salmond, George P C

    2012-03-01

    Serratia sp. ATCC 39006 (S39006) is a Gram-negative bacterium that is virulent in plant (potato) and invertebrate animal (Caenorhabditis elegans) models. It produces two secondary metabolite antibiotics, a prodigiosin and a carbapenem, and the exoenzymes pectate lyase and cellulase. We showed previously that deletion of the RNA chaperone Hfq abolished antibiotic production and attenuated virulence in both animal and plant hosts. Hfq and dependent small RNAs (sRNAs) are known to regulate the post-transcriptional expression of rpoS, which encodes σ(S), the stationary phase sigma factor subunit of RNA polymerase. An S39006 hfq deletion mutant showed decreased transcript levels of rpoS. Therefore, in this study we investigated whether the phenotypes regulated by Hfq were mediated through its control of rpoS. Whereas loss of Hfq abolished prodigiosin and carbapenem production and attenuated virulence in both C. elegans and potato, characterization of an S39006 rpoS mutant showed unexpectedly elevated prodigiosin and carbapenem production. Furthermore, the rpoS mutant exhibited attenuated animal pathogenesis, but not plant pathogenesis. Additionally, a homologue of the Hfq-dependent sRNA, RprA, was identified and shown to regulate prodigiosin production in a manner consistent with its role in positively regulating translation of rpoS mRNA. Combined, these results demonstrate that Hfq regulation of secondary metabolism and plant pathogenesis is independent of RpoS and establishes RpoS and RprA as regulators of antibiotic production.

  7. The anti-sigma factor TcdC modulates hypervirulence in an epidemic BI/NAP1/027 clinical isolate of Clostridium difficile.

    Directory of Open Access Journals (Sweden)

    Glen P Carter

    2011-10-01

    Full Text Available Nosocomial infections are increasingly being recognised as a major patient safety issue. The modern hospital environment and associated health care practices have provided a niche for the rapid evolution of microbial pathogens that are well adapted to surviving and proliferating in this setting, after which they can infect susceptible patients. This is clearly the case for bacterial pathogens such as Methicillin Resistant Staphylococcus aureus (MRSA and Vancomycin Resistant Enterococcus (VRE species, both of which have acquired resistance to antimicrobial agents as well as enhanced survival and virulence properties that present serious therapeutic dilemmas for treating physicians. It has recently become apparent that the spore-forming bacterium Clostridium difficile also falls within this category. Since 2000, there has been a striking increase in C. difficile nosocomial infections worldwide, predominantly due to the emergence of epidemic or hypervirulent isolates that appear to possess extended antibiotic resistance and virulence properties. Various hypotheses have been proposed for the emergence of these strains, and for their persistence and increased virulence, but supportive experimental data are lacking. Here we describe a genetic approach using isogenic strains to identify a factor linked to the development of hypervirulence in C. difficile. This study provides evidence that a naturally occurring mutation in a negative regulator of toxin production, the anti-sigma factor TcdC, is an important factor in the development of hypervirulence in epidemic C. difficile isolates, presumably because the mutation leads to significantly increased toxin production, a contentious hypothesis until now. These results have important implications for C. difficile pathogenesis and virulence since they suggest that strains carrying a similar mutation have the inherent potential to develop a hypervirulent phenotype.

  8. Sigma models on supercosets

    Energy Technology Data Exchange (ETDEWEB)

    Mitev, Vladimir

    2010-08-15

    The purpose of this thesis is to deepen our understanding of the fundamental properties and defining features of non-linear sigma models on superspaces. We begin by presenting the major concepts that we have used in our investigation, namely Lie superalgebras and supergroups, non-linear sigma models and two dimensional conformal field theory. We then exhibit a method, called cohomological reduction, that makes use of the target space supersymmetry of non-linear sigma models to compute certain correlation functions. We then show how the target space supersymmetry of Ricci flat Lie supergroups simplifies the perturbation theory of suitable deformed Wess-Zumino-Witten models, making it possible to compute boundary conformal weights to all orders. This is then applied to the OSP (2S+2 vertical stroke 2S) Gross-Neveu Model, leading to a dual description in terms of the sigma model on the supersphere S{sup 2S+1} {sup vertical} {sup stroke} {sup 2S}. With this results in mind, we then turn to the similar, yet more intricate, theory of the non-linear sigma model on the complex projective superspaces CP{sup N-1} {sup vertical} {sup stroke} {sup N}. The cohomological reduction allows us to compute several important quantities non-perturbatively with the help of the system of symplectic fermions. Combining this with partial perturbative results for the whole theory, together with numerical computations, we propose a conjecture for the exact evolution of boundary conformal weights for symmetry preserving boundary conditions. (orig.)

  9. Sigma models on supercosets

    International Nuclear Information System (INIS)

    Mitev, Vladimir

    2010-08-01

    The purpose of this thesis is to deepen our understanding of the fundamental properties and defining features of non-linear sigma models on superspaces. We begin by presenting the major concepts that we have used in our investigation, namely Lie superalgebras and supergroups, non-linear sigma models and two dimensional conformal field theory. We then exhibit a method, called cohomological reduction, that makes use of the target space supersymmetry of non-linear sigma models to compute certain correlation functions. We then show how the target space supersymmetry of Ricci flat Lie supergroups simplifies the perturbation theory of suitable deformed Wess-Zumino-Witten models, making it possible to compute boundary conformal weights to all orders. This is then applied to the OSP (2S+2 vertical stroke 2S) Gross-Neveu Model, leading to a dual description in terms of the sigma model on the supersphere S 2S+1 vertical stroke 2S . With this results in mind, we then turn to the similar, yet more intricate, theory of the non-linear sigma model on the complex projective superspaces CP N-1 vertical stroke N . The cohomological reduction allows us to compute several important quantities non-perturbatively with the help of the system of symplectic fermions. Combining this with partial perturbative results for the whole theory, together with numerical computations, we propose a conjecture for the exact evolution of boundary conformal weights for symmetry preserving boundary conditions. (orig.)

  10. Testing the Scale Dependence of the Scale Factor $\\sigma_{eff}$ in Double Dijet Production at the LHC

    CERN Document Server

    Domdey, Svend; Wiedemann, Urs Achim

    2010-01-01

    The scale factor σ eff is the effective cross section used to characterize the measured rate of inclusive double dijet production in high energy hadron collisions. It is sensitive to the two-parton distributions in the hadronic projectile. In principle, the scale factor depends on the center of mass energy and on the minimal transverse energy of the jets contributing to the double dijet cross section. Here, we point out that proton-proton collisions at the LHC will provide for the first time experimental access to these scale dependences in a logarithmically wide, nominally perturbative kinematic range of minimal transverse energy between 10 GeV and 100 GeV. This constrains the dependence of two-parton distribution functions on parton momentum fractions and parton localization in impact parameter space. Novel information is to be expected about the transverse growth of hadronic distribution functions in the range of semi-hard Bjorken x (0.001 < x < 0.1) and high resolution Q^2. We discuss to what exten...

  11. Abscisic acid affects transcription of chloroplast genes via protein phosphatase 2C-dependent activation of nuclear genes: repression by guanosine-3'-5'-bisdiphosphate and activation by sigma factor 5.

    Science.gov (United States)

    Yamburenko, Maria V; Zubo, Yan O; Börner, Thomas

    2015-06-01

    Abscisic acid (ABA) represses the transcriptional activity of chloroplast genes (determined by run-on assays), with the exception of psbD and a few other genes in wild-type Arabidopsis seedlings and mature rosette leaves. Abscisic acid does not influence chloroplast transcription in the mutant lines abi1-1 and abi2-1 with constitutive protein phosphatase 2C (PP2C) activity, suggesting that ABA affects chloroplast gene activity by binding to the pyrabactin resistance (PYR)/PYR1-like or regulatory component of ABA receptor protein family (PYR/PYL/RCAR) and signaling via PP2Cs and sucrose non-fermenting protein-related kinases 2 (SnRK2s). Further we show by quantitative PCR that ABA enhances the transcript levels of RSH2, RSH3, PTF1 and SIG5. RelA/SpoT homolog 2 (RSH2) and RSH3 are known to synthesize guanosine-3'-5'-bisdiphosphate (ppGpp), an inhibitor of the plastid-gene-encoded chloroplast RNA polymerase. We propose, therefore, that ABA leads to an inhibition of chloroplast gene expression via stimulation of ppGpp synthesis. On the other hand, sigma factor 5 (SIG5) and plastid transcription factor 1 (PTF1) are known to be necessary for the transcription of psbD from a specific light- and stress-induced promoter (the blue light responsive promoter, BLRP). We demonstrate that ABA activates the psbD gene by stimulation of transcription initiation at BLRP. Taken together, our data suggest that ABA affects the transcription of chloroplast genes by a PP2C-dependent activation of nuclear genes encoding proteins involved in chloroplast transcription. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  12. Factors Associated with Urinary Stress Incontinence in Primiparas

    OpenAIRE

    Pei-Ling Chou; Fang-Ping Chen; Li-Fen Teng

    2005-01-01

    Objective: To evaluate obstetric and maternal risk factors for stress urinary incontinence in primiparas. Materials and Methods: From January 2001 to August 2002, 378 primiparas were interviewed about stress urinary incontinence 1 year after delivery. The association between symptoms of urinary stress incontinence and obstetric factors was assessed. Results: Twenty-four (6%) primiparas had urinary stress incontinence after delivery. Maternal age was positively associated with urinary st...

  13. Inclusive $\\Sigma^{+}$ and $\\Sigma^{0}$ Production in Hadronic Z Decays

    CERN Document Server

    Acciarri, M.; Adriani, O.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Ambrosi, G.; Anderhub, H.; Andreev, Valery P.; Angelescu, T.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, L.; Balandras, A.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Barone, L.; Bartalini, P.; Basile, M.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Bhattacharya, S.; Biasini, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brigljevic, V.; Brochu, F.; Buffini, A.; Buijs, A.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Campanelli, Mario; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.M.; Casaus, J.; Castellini, G.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Cesaroni, F.; Chamizo, M.; Chang, Y.H.; Chaturvedi, U.K.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Civinini, C.; Clare, I.; Clare, R.; Coignet, G.; Colijn, A.P.; Colino, N.; Costantini, S.; Cotorobai, F.; Cozzoni, B.; de la Cruz, B.; Csilling, A.; Cucciarelli, S.; Dai, T.S.; van Dalen, J.A.; D'Alessandro, R.; de Asmundis, R.; Deglon, P.; Degre, A.; Deiters, K.; della Volpe, D.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; van Dierendonck, D.; Di Lodovico, F.; Dionisi, C.; Dittmar, M.; Dominguez, A.; Doria, A.; Dova, M.T.; Duchesneau, D.; Dufournaud, D.; Duinker, P.; Duran, I.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Erne, F.C.; Extermann, P.; Fabre, M.; Faccini, R.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Ferroni, F.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisk, I.; Forconi, G.; Fredj, L.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gau, S.S.; Gentile, S.; Gheordanescu, N.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; van Gulik, R.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hasan, A.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hidas, P.; Hirschfelder, J.; Hofer, H.; Holzner, G.; Hoorani, H.; Hou, S.R.; Hu, Y.; Iashvili, I.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Khan, R.A.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, D.; Kim, J.K.; Kirkby, Jasper; Kiss, D.; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopp, A.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Krenz, W.; Kruger, A.; Kunin, A.; Ladron Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lassila-Perini, K.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, H.J.; Le Goff, J.M.; Leiste, R.; Leonardi, Emanuele; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Lubelsmeyer, K.; Luci, C.; Luckey, David; Lugnier, L.; Luminari, L.; Lustermann, W.; Ma, W.G.; Maity, M.; Malgeri, L.; Malinin, A.; Mana, C.; Mangeol, D.; Mans, J.; Marchesini, P.; Marian, G.; Martin, J.P.; Marzano, F.; Massaro, G.G.G.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; von der Mey, M.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Molnar, P.; Monteleoni, B.; Moulik, T.; Muanza, G.S.; Muheim, F.; Muijs, A.J.M.; Musy, M.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Niessen, T.; Nisati, A.; Kluge, Hannelies; Organtini, G.; Oulianov, A.; Palomares, C.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Paramatti, R.; Park, H.K.; Park, I.H.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pieri, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Pothier, J.; Produit, N.; Prokofev, D.O.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, M.A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Raspereza, A.; Raven, G.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; van Rhee, T.; Riemann, S.; Riles, Keith; Robohm, A.; Rodin, J.; Roe, B.P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Rubio, J.A.; Ruschmeier, D.; Rykaczewski, H.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Sanders, M.P.; Sarakinos, M.E.; Schafer, C.; Schegelsky, V.; Schmidt-Kaerst, S.; Schmitz, D.; Schopper, H.; Schotanus, D.J.; Schwering, G.; Sciacca, C.; Sciarrino, D.; Seganti, A.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Siedenburg, T.; Son, D.; Smith, B.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stone, A.; Stone, H.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Suter, H.; Swain, J.D.; Szillasi, Z.; Sztaricskai, T.; Tang, X.W.; Tauscher, L.; Taylor, L.; Tellili, B.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Uchida, Y.; Ulbricht, J.; Valente, E.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobov, A.A.; Vorvolakos, A.; Wadhwa, M.; Wallraff, W.; Wang, M.; Wang, X.L.; Wang, Z.M.; Weber, A.; Weber, M.; Wienemann, P.; Wilkens, H.; Wu, S.X.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Ye, J.B.; Yeh, S.C.; Zalite, A.; Zalite, Yu.; Zhang, Z.P.; Zhu, G.Y.; Zhu, R.Y.; Zichichi, A.; Zilizi, G.; Zoller, M.

    2000-01-01

    We report on measurements of the inclusive production rate of $\\Sigma^+$ and $\\Sigma^0$ baryons in hadronic Z decays collected with the L3 detector at LEP. The $\\Sigma^+$ baryons are detected through the decay $\\Sigma^+ \\rightarrow {\\rm p} \\pi^0$, while the $\\Sigma^0$ baryons are detected via the decay mode $\\Sigma^0 \\rightarrow \\Lambda \\gamma$. The average numbers of $\\Sigma^+$ and $\\Sigma^0$ per hadronic Z decay are measured to be: \\begin{eqnarray*} \\left + \\left & = & 0.114 \\pm 0.011_{\\mbox{\\it \\small stat}} \\pm 0.009_{\\mbox{\\it \\small syst}} \\\\ \\left + \\left & = & 0.095 \\pm 0.015_{\\mbox{\\it \\small stat}} \\pm 0.013_{\\mbox{\\it \\small syst}} \\ \\mbox{.} \\end{eqnarray*} These rates are found to be higher than the predictions from Monte Carlo hadronization models and analytical parameterizations of strange baryon production.

  14. Sigma-1 receptor: The novel intracellular target of neuropsychotherapeutic drugs

    Directory of Open Access Journals (Sweden)

    Teruo Hayashi

    2015-01-01

    Full Text Available Sigma-1 receptor ligands have been long expected to serve as drugs for treatment of human diseases such as neurodegenerative disorders, depression, idiopathic pain, drug abuse, and cancer. Recent research exploring the molecular function of the sigma-1 receptor started unveiling underlying mechanisms of the therapeutic activity of those ligands. Via the molecular chaperone activity, the sigma-1 receptor regulates protein folding/degradation, ER/oxidative stress, and cell survival. The chaperone activity is activated or inhibited by synthetic sigma-1 receptor ligands in an agonist-antagonist manner. Sigma-1 receptors are localized at the endoplasmic reticulum (ER membranes that are physically associated with the mitochondria (MAM: mitochondria-associated ER membrane. In specific types of neurons (e.g., those at the spinal cord, sigma-1 receptors are also clustered at ER membranes that juxtapose postsynaptic plasma membranes. Recent studies indicate that sigma-1 receptors, partly in sake of its unique subcellular localization, regulate the mitochondria function that involves bioenergetics and free radical generation. The sigma-1 receptor may thus provide an intracellular drug target that enables controlling ER stress and free radical generation under pathological conditions.

  15. Down-regulation of outer membrane proteins by noncoding RNAs: unraveling the cAMP-CRP- and sigmaE-dependent CyaR-ompX regulatory case

    DEFF Research Database (Denmark)

    Johansen, Jesper; Eriksen, Maiken; Kallipolitis, Birgitte

    2008-01-01

    is sufficient to trigger the envelope stress response. Recent work indicates that small Hfq-binding RNAs play a major role in maintaining envelope homeostasis and, so far, two sigma(E)-dependent small noncoding RNAs (sRNAs), MicA and RybB, have been shown to facilitate rapid removal of multiple omp transcripts......The sigma(E) (extracytoplasmic stress response sigma factor in Escherichia coli) signaling system of Gram-negative bacteria plays an essential role in the maintenance of the extracytoplasmic compartment. Upon induction of this system, approximately 100 genes are up-regulated. The majority...... is also up-regulated, directly or indirectly, by sigma(E). In addition, this work identified MicA as a factor that cooperates in the negative control of ompX expression. The conservation of CyaR, MicA, RybB, and their targets suggests that the omp mRNA-sRNA regulatory network is an integral part...

  16. Six Sigma method

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Mast, J.; Balakrishnan, N.; Brandimarte, P.; Everitt, B.; Molenberghs, G.; Piegorsch, W.; Ruggeri, F.

    2015-01-01

    Six Sigma is built on principles and methods that have proven themselves over the twentieth century. It has incorporated the most effective approaches and integrated them into a full program. It offers a management structure for organizing continuous improvement of routine tasks, such as

  17. The extracytoplasmic function sigma factor SigV plays a key role in the original model of lysozyme resistance and virulence of Enterococcus faecalis.

    Directory of Open Access Journals (Sweden)

    André Le Jeune

    Full Text Available BACKGROUND: Enterococcus faecalis is one of the leading agents of nosocomial infections. To cause diseases, pathogens or opportunistic bacteria have to adapt and survive to the defense systems encountered in the host. One of the most important compounds of the host innate defense response against invading microorganisms is lysozyme. It is found in a wide variety of body fluids, as well as in cells of the innate immune system. Lysozyme could act either as a muramidase and/or as a cationic antimicrobial peptide. Like Staphylococcus aureus, E. faecalis is one of the few bacteria that are completely lysozyme resistant. RESULTS: This study revealed that oatA (O-acetyl transferase and dlt (D-Alanylation of lipoteicoic acids genes contribute only partly to the lysozyme resistance of E. faecalis and that a specific transcriptional regulator, the extracytoplasmic function SigV sigma factor plays a key role in this event. Indeed, the sigV single mutant is as sensitive as the oatA/dltA double mutant, and the sigV/oatA/dltA triple mutant displays the highest level of lysozyme sensitivity suggesting synergistic effects of these genes. In S. aureus, mutation of both oatA and dlt genes abolishes completely the lysozyme resistance, whereas this is not the case in E. faecalis. Interestingly SigV does not control neither oatA nor dlt genes. Moreover, the sigV mutants clearly showed a reduced capacity to colonize host tissues, as they are significantly less recovered than the parental JH2-2 strain from organs of mice subjected to intravenous or urinary tract infections. CONCLUSIONS: This work led to the discovery of an original model of lysozyme resistance mechanism which is obviously more complex than those described for other Gram positive pathogens. Moreover, our data provide evidences for a direct link between lysozyme resistance and virulence of E. faecalis.

  18. Use of frozen stress in extracting stress intensity factor distributions in three dimensional cracked body problems

    Science.gov (United States)

    Smith, C. W.

    1992-01-01

    The adaptation of the frozen stress photoelastic method to the determination of the distribution of stress intensity factors in three dimensional problems is briefly reviewed. The method is then applied to several engineering problems of practical significance.

  19. gender and school types as factors responsible for job stress

    African Journals Online (AJOL)

    Emeka Egbochuku

    public Universities should be looked into so that all factors responsible for stress might be .... universities in Malaysia, university academic staffs faced more problems .... adjustment with different coping styles. .... in college students: The role of rumination and stress. ... International Journal of Stress Management, 8, 285–29.

  20. Development of radiolabeled probes directed against sigma-1 receptors

    International Nuclear Information System (INIS)

    Ogawa, Kazuma; Masuda, Ryohei; Shiba, Kazuhiro

    2017-01-01

    It has been reported that sigma-1 receptors regulate the release of signaling substances in the central nervous systems and are related to various diseases, such as schizophrenia, stress disorders, dementia, amyotrophic lateral sclerosis (ALS), and cancer. If the quantification of the sigma-1 receptors is possible, the pathophysiology, the stage, and the early detection of the diseases could be understandable. Molecular imaging using Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT) and radioactive probes makes noninvasive quantification of the in vivo metabolism and function possible. Currently, only nuclear medicine diagnosis using PET or SPECT can quantify the sigma-1 receptors. Therefore, there is great expectation for the development of molecular probes to image the sigma-1 receptors specifically. In this paper, we introduce our research on the development of radiohalogen-labeled molecular probes directed against the sigma-1 receptors. (author)

  1. Childhood Stress : Stressors, Coping, and Factors.

    NARCIS (Netherlands)

    Nijboer, J.M.

    2007-01-01

    Burnout is a matter of imbalance in life very often (Nijboer, 2006). In order to know more about imbalance and exhaustion in children, stress and coping in children will be investigated in this literature study. The goal is to identify common childhood stressors, the ways children cope with stress,

  2. The maximum possible stress intensity factor for a crack in an unknown residual stress field

    International Nuclear Information System (INIS)

    Coules, H.E.; Smith, D.J.

    2015-01-01

    Residual and thermal stress fields in engineering components can act on cracks and structural flaws, promoting or inhibiting fracture. However, these stresses are limited in magnitude by the ability of materials to sustain them elastically. As a consequence, the stress intensity factor which can be applied to a given defect by a self-equilibrating stress field is also limited. We propose a simple weight function method for determining the maximum stress intensity factor which can occur for a given crack or defect in a one-dimensional self-equilibrating stress field, i.e. an upper bound for the residual stress contribution to K I . This can be used for analysing structures containing defects and subject to residual stress without any information about the actual stress field which exists in the structure being analysed. A number of examples are given, including long radial cracks and fully-circumferential cracks in thick-walled hollow cylinders containing self-equilibrating stresses. - Highlights: • An upper limit to the contribution of residual stress to stress intensity factor. • The maximum K I for self-equilibrating stresses in several geometries is calculated. • A weight function method can determine this maximum for 1-dimensional stress fields. • Simple MATLAB scripts for calculating maximum K I provided as supplementary material.

  3. Sigma virus and mutation in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Paquin, S.L.A.

    1977-01-01

    - The objectives of these experiments have been (1) to verify and evidence more fully the action of sigma in causing recessive lethal mutation on the X chromosome of Drosophila, both in the male and the female germ line; (2) to extend the study of sigma-induced recessive lethal mutation to the Drosophila autosomes; (3) to explore the possibility that this mutagenesis is site-directed; (4) to study the effects of sigma virus in conjunction with radiation in increasing non-disjunction and dominant lethality. The virus increases the rate of radiation-induced nondisjunction by altering meiotic chromosomal behavior. Percentage of non-disjunction with 500 rads of x-rays in the virus-free flies was 0.176, while in sigma-containing lines it was 0.333. With high doses of either x or neutron radiation, the presence of the virus enhances the frequency of dominant lethality. The difference is especially significant with the fast neutrons. The results indicate that sigma, and presumably other viruses, are indeed environmental mutagens and are, therefore, factors in the rate of background or spontaneous mutation

  4. Estimation of stress intensity factors for circumferential cracked pipes under welding residual stress filed

    International Nuclear Information System (INIS)

    Oh, Chang Young; Kim, Yun Jae; Oh, Young Jin; Song, Tae Kwang; Kim, Yong Beum; Oh, Young Jin; Song, Tae Kwang; Kim, Yong Beum

    2012-01-01

    Recently, stress corrosion cracking(SCC) have been found in dissimilar metal welds of nozzles in some pressurized water reactors and on low carbon stainless steel piping systems of boiling water reactors. The important factor of SCC is the residual stress field caused by weld. For the evaluation of crack growth analysis due to SCC, stress intensity factor under a residual stress field should be estimated. Several solutions for stress intensity factor under residual stress field were recommended in flaw assessment codes such as the American Society of Mechanical Engineers (ASME) Section XI, R6, American Petroleum Institute (API579). Some relevant works have been studied. Dong et al. evaluated stress intensity factors in welded structures. Miyazaki et al. estimated stress intensity factors of surface crack in simple stress fields. This paper presents a simple method to estimate stress intensity factors in welding residual stress field. For general application, results of structure integrity assessment codes KI solutions were compared Finite element analyses of welding simulation and cracked pipes are described. Comparison results of KI solutions and proposed simplified solution are presented in the works

  5. DESIGN FOR SIX SIGMA

    Directory of Open Access Journals (Sweden)

    Liem Ferryanto

    2007-01-01

    Full Text Available This article provides a step by step process of executing analytical or computer based Design for Six Sigma using a Sliding Door project as an example. It comprises of identification of Voice Of the Customer (VOC, transformation of VOC to what it is called Critical To Quality characteristics (CTQs, modeling of system transfers function, optimal and robust solutions, and tolerance design approach

  6. SIGMA Experimental Facility

    International Nuclear Information System (INIS)

    Rivarola, Martin; Florido, Pablo; Gonzalez, Jose; Brasnarof, Daniel; Orellano, Pablo; Bergallo, Juan

    2000-01-01

    The SIGMA ( Separacion Isotopica Gaseosa por Metodos Avanzados) concept is outlined.The old gaseous diffusion process to enrich uranium has been updated to be economically competitive for small production volumes.Major innovations have been introduced in the membrane design and in the integrated design of compressors and diffusers.The use of injectors and gas turbines has been also adopted.The paper describes the demonstration facility installed by the Argentine Atomic Energy Commission

  7. ORGANIZATIONAL AND PERSONALITY FACTORS OF STRESS IN ACCOUNTING AND CONSEQUENCES OF STRESS ON HEALTH

    OpenAIRE

    Vesna Stager

    2017-01-01

    Stress in accounting is popular in the area of research for many researchers in the fields of Psychology, Organizational Behavior, Health and Medicine. A significant part of empirical research has been focused on the analysis of the relationships between different individual and organizational stress factors on the job, including the effects of stress on the job. In the paper, we are showing an overview of the key concepts in the field of stress in accounting, covering organizational and pers...

  8. Evaluation of stress intensity factors due to welding residual stresses for circumferential cracked pipes

    International Nuclear Information System (INIS)

    Oh, Chang-Young; Kim, Yun-Jae; Oh, Young-Jin; Kim, Jong-Sung; Song, Tae-Kwang; Kim, Yong-Beum

    2013-01-01

    To investigate the applicability of existing methods to estimate stress intensity factors due to welding residual stresses, comparisons with finite element (FE) solutions are made for two types of generic welding residual stress profiles, generated by simulating repair welds. It is found that fitting residual stresses over the crack depth using third-order polynomials gives good estimates of stress intensity factors but fitting over the entire thickness can result in inaccurate estimates even with fourth-order polynomials. Noting that welding residual stresses are often determined from FE analyses, linearization of residual stresses to estimate stress intensity factors is proposed. Comparison with FE solutions shows good agreements. -- Highlights: ► Applicability of K estimation methods is investigated for welding residual stresses. ► Two types of generic residual stress profiles with repair welds are considered. ► Fitting residual stresses over the crack depth gives good estimates of K. ► A method to estimate K by linearising residual stress profiles is proposed

  9. sigma54-Mediated control of the mannose phosphotransferase sytem in Lactobacillus plantarum impacts on carbohydrate metabolism

    NARCIS (Netherlands)

    Stevens, M.J.A.; Molenaar, D.; Jong, de A.; Vos, de W.M.; Kleerebezem, M.

    2010-01-01

    Sigma factors direct specific binding of the bacterial RNA polymerase to the promoter. Here we present the elucidation of the sigma(54 ) regulon in Lactobacillus plantarum. A sequence-based regulon prediction of sigma(54)-dependent promoters revealed an operon encoding a mannose phosphotransferase

  10. sigma(54)-mediated control of the mannose phosphotransferase sytem in Lactobacillus plantarum impacts on carbohydrate metabolism

    NARCIS (Netherlands)

    Stevens, Marc J. A.; Molenaar, Douwe; de Jong, Anne; De Vos, Willem M.; Kleerebezem, Michiel

    Sigma factors direct specific binding of the bacterial RNA polymerase to the promoter. Here we present the elucidation of the sigma(54) regulon in Lactobacillus plantarum. A sequence-based regulon prediction of sigma(54)-dependent promoters revealed an operon encoding a mannose phosphotransferase

  11. Chronic stress as a factor in aircraft mishaps

    Science.gov (United States)

    Alkov, Robert A.

    1988-01-01

    Naval aviation is an unusually stressful career because of the inherent demands of the work. Stress is recognized as a cause of mishaps which involve pilot error. A questionnaire was adapted from Rahe and Homes' list of stressful life events in order to determine the relationship between pilot behavioral, personality, and life change factors on the one hand and responsibility for accidents on the other. A number of factors regarding interpersonal relationships, changes in personal behavior, personality factors, and life changes were found to discriminate between pilots who were and were not at fault in accidents.

  12. Imaging shear stress distribution and evaluating the stress concentration factor of the human eye

    Science.gov (United States)

    Joseph Antony, S.

    2015-03-01

    Healthy eyes are vital for a better quality of human life. Historically, for man-made materials, scientists and engineers use stress concentration factors to characterise the effects of structural non-homogeneities on their mechanical strength. However, such information is scarce for the human eye. Here we present the shear stress distribution profiles of a healthy human cornea surface in vivo using photo-stress analysis tomography, which is a non-intrusive and non-X-ray based method. The corneal birefringent retardation measured here is comparable to that of previous studies. Using this, we derive eye stress concentration factors and the directional alignment of major principal stress on the surface of the cornea. Similar to thermometers being used for monitoring the general health in humans, this report provides a foundation to characterise the shear stress carrying capacity of the cornea, and a potential bench mark for validating theoretical modelling of stresses in the human eye in future.

  13. Stress factors for the deformation systems of zirconium under multiaxial stress

    International Nuclear Information System (INIS)

    Hobson, D.O.

    1976-01-01

    Calculation of the resolved shear stresses (rss) that act on various deformation systems in metals and, in particular, the determination of those systems subjected to the highest rss by a given set of multiaxial stresses is of importance in the study of texture development, yielding and plastic flow. This study examines the geometrical influences of any stress state on the deformation modes of zirconium. One slip mode and three twinning modes, comprising twenty-one deformation systems, are considered. Stress factors computed for these systems are shown on a coordinate system that allows specimen orientation, most highly stressed deformation system, and stress factor to be shown without ambiguity. The information in this report allows the determination of the rss that results from any multiaxial stress state; this information also allows the prediction of the deformation modes that might operate for any specimen orientation in that strss state

  14. Factors causing stress among Pakistani working women

    OpenAIRE

    Arif, Ahmed; Naveed, Shaheryar; Aslam, Ramsha

    2017-01-01

    Women are traditionally considered to be confined within the four walls of their houses in the developing countries. They are still unable to play an active role in the development of society. They are striving to make their identity as an integral part of the society. Being a member of conservative developing society, women are still facing many hindrances, causing stressful situation for them, which prohibits them to participate actively in the economic development. This paper attempts to e...

  15. Factor associated with stress among parents of children with autism

    International Nuclear Information System (INIS)

    Shahida, S.; Khurshid, S.

    2015-01-01

    To determine the factors associated with stress among parents of children with autism. Study Design: A cross-sectional field survey study. Place and Duration of Study: Department of Psychology, GC University, Lahore, from September 2012 to November 2013. Methodology: The sample consisted of 100 parents (50 mothers and 50 fathers) of children with autism. Measures of childhood autism rating, sense of coherence, parenting self-efficacy, parenting stress, and demographic data sheet were completed by the parents in outdoor units of children hospital, institutes, and at their homes. Results: Significant correlations were found between severity of impairment and parenting stress (r = .53, p < .01), between parenting self-efficacy and parenting stress (r = -.35, p < .01, and between sense of coherence and parenting stress (r = -.26, p < .05). No significant gender difference emerged in terms of parenting self-efficacy, sense of coherence, and parenting stress. Results of stepwise regression partially supported our hypothesized model, as severity of child impairment, and parenting self-efficacy appeared as significant predictors of parenting stress (R2 = .35). However, there was no evidence of role of demographic variables in the parenting stress. Conclusion: The severity of child's impairment emerged as the most salient risk factor for parenting stress; however, it was concluded that parents ability and confidence in their competence of parenting a child in challenging situations may reduce their stress. (author)

  16. Work stress and metabolic and hemostatic risk factors

    NARCIS (Netherlands)

    Vrijkotte, T. G.; van Doornen, L. J.; de Geus, E. J.

    1999-01-01

    A high level of work stress has been associated with cardiovascular disease. However, the pathophysiological mechanisms underlying this association remain unclear. This study examined the effect of work stress on a cluster of metabolic and hemostatic risk factors. Blood was collected three times, on

  17. Numerical Determination of Crack Opening and Closure Stress Intensity Factors

    DEFF Research Database (Denmark)

    Ricardo, Luiz Carlos Hernandes

    2009-01-01

    The present work shows the numerical determination of fatigue crack opening and closure stress intensity factors of a C(T) specimen under variable amplitude loading using a finite element method. A half compact tension C(T) specimen, assuming plane stress constraint was used by finite element...

  18. A Factor Analytic Study of the Teaching Events Stress Inventory.

    Science.gov (United States)

    Alexander, Livingston; And Others

    The purpose of this study was to determine if definitive factors emerge from the responses of teachers to the Teaching Events Stress Inventory (TESI). In a series of three studies during the years 1980 to 1982, data were collected to assess the levels and sources of stress experienced by 660 teachers in central and western Kentucky. The subjects…

  19. Intrinsic factors associated with medial tibial stress syndrome in ...

    African Journals Online (AJOL)

    Intrinsic factors associated with medial tibial stress syndrome in athletes: A large case-control study. ... Medial tibial stress syndrome (MTSS) is the most common lower-leg injury in athletes, and is thought to be caused by ... from 32 Countries:.

  20. Subjective stress factors in centrifuge training for military aircrews.

    Science.gov (United States)

    Lin, Pei-Chun; Wang, Jenhung; Li, Shih-Chin

    2012-07-01

    This study investigates stress-influence factors perceived by military aircrews undergoing centrifuge training, which lowers the incidence of G-induced loss of consciousness (G-LOC) for the crews of high-performance combat aircrafts. We used questionnaires to assess the subjective stress-influence factors of crews undergoing centrifuge training. Professionals in aviation physiology identified attributes measuring the perceived stress induced by centrifuge training, which were segmented into three constructs by factor analysis, theory lecture, centrifuge equipment, and physical fitness. Considerable interpenetration was discernible between these factors and military rank, age, length of service, flight hours accrued, and type of aircraft piloted. Identifying and quantifying the perceived stressors experienced in human-use centrifuge training enables aviators, astronauts, and air forces of the world to determine which constructs perceptibly increase or alleviate the perceived stress undergone by trainees when partaking in centrifuge training. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  1. Stress indices and flexibility factors in thin elbows

    International Nuclear Information System (INIS)

    Berton, M.N.; Carbonnier, J.L.

    1983-01-01

    Usually piping calculations are done with a beam model. Ovalisation in elbows is taken into account by the means of flexibility factors and stress indices. This paper compares results from a beam model calculation with results from a 3 D shell model calculation. (codes TEDEL and TRICO from the CEA-SEMT System). The aim of this comparison is to study the validity of the stress indices and flexibility factors used in the beam model for several kinds of loading

  2. Sigma beta decay

    International Nuclear Information System (INIS)

    Newman, D.E.

    1975-01-01

    Describes an experiment to measure beta decays of the sigma particle. Sigmas produced by stopping a K - beam in a liquid hydrogen target decayed in the following reactions: Kp → Σπ; Σ → Neν. The electron and pion were detected by wire spark chambers in a magnetic spectrometer and by plastic scintillators, and were differentiated by a threshold gas Cherenkov counter. The neutron was detected by liquid scintillation counters. The data (n = 3) shell electrons or the highly excited electrons decay first. Instead, it is suggested that when there are two to five electrons in highly excited states immediately after a heavy ion--atom collision the first transitions to occur will be among highly excited Rydberg states in a cascade down to the 4s, 4p, and 3d-subshells. If one of the long lived states becomes occupied by electrons promoted during the collision or by electrons falling from higher levels, it will not decay until after the valence shell decays. LMM rates calculated to test the methods used are compared to previous works. The mixing coefficients are given in terms of the states 4s4p, 45sp+-, and 5s5p. The applicability of Cooper, Fano, and Prats' discussion of the energies and transition rates of doubly excited states is considered

  3. Observation of the Heavy Baryons Sigma b and Sigma b*.

    Science.gov (United States)

    Aaltonen, T; Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Cilijak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; DaRonco, S; Datta, M; D'Auria, S; Davies, T; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Dörr, C; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraan, A C; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moon, C S; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shalhout, S Z; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuno, S; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vazquez, F; Velev, G; Vellidis, C; Veramendi, G; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Vollrath, I; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S

    2007-11-16

    We report an observation of new bottom baryons produced in pp collisions at the Tevatron. Using 1.1 fb(-1) of data collected by the CDF II detector, we observe four Lambda b 0 pi+/- resonances in the fully reconstructed decay mode Lambda b 0-->Lambda c + pi-, where Lambda c+-->pK* pi+. We interpret these states as the Sigma b(*)+/- baryons and measure the following masses: m Sigma b+=5807.8 -2.2 +2.0(stat.)+/-1.7(syst.) MeV/c2, m Sigma b- =5815.2+/-1.0(stat.)+/-1.7(syst.) MeV/c2, and m(Sigma b*)-m(Sigma b)=21.2-1.9 +2.0(stat.)-0.3+0.4(syst.) MeV/c2.

  4. Occupational stress and related factors among surgical residents in Korea.

    Science.gov (United States)

    Kang, Sanghee; Jo, Hye Sung; Boo, Yoon Jung; Lee, Ji Sung; Kim, Chong Suk

    2015-11-01

    The application rate for surgical residents in Korea has continuously decreased over the past few years. The demanding workload and the occupational stress of surgical training are likely causes of this problem. The aim of this study was to investigate occupational stress and its related factors in Korean surgical residents. With the support of the Korean Surgical Society, we conducted an electronic survey of Korean surgical residents related to occupational stress. We used the Korean Occupational Stress Scale (KOSS) to measure occupational stress. We analyzed the data focused on the stress level and the factors associated with occupational stress. The mean KOSS score of the surgical residents was 55.39, which was significantly higher than that of practicing surgeons (48.16, P occupation rate and exercise were all significantly associated with KOSS score. Surgical residents have high occupational stress compared to practicing surgeons and other professionals. Their mean number of assigned patients, resident recruitment rate and exercise were all significantly associated with occupational stress for surgical residents.

  5. Stress as a common risk factor for obesity and addiction.

    Science.gov (United States)

    Sinha, Rajita; Jastreboff, Ania M

    2013-05-01

    Stress is associated with obesity, and the neurobiology of stress overlaps significantly with that of appetite and energy regulation. This review will discuss stress, allostasis, the neurobiology of stress and its overlap with neural regulation of appetite, and energy homeostasis. Stress is a key risk factor in the development of addiction and in addiction relapse. High levels of stress changes eating patterns and augments consumption of highly palatable (HP) foods, which in turn increases incentive salience of HP foods and allostatic load. The neurobiological mechanisms by which stress affects reward pathways to potentiate motivation and consumption of HP foods as well as addictive drugs is discussed. With enhanced incentive salience of HP foods and overconsumption of these foods, there are adaptations in stress and reward circuits that promote stress-related and HP food-related motivation as well as concomitant metabolic adaptations, including alterations in glucose metabolism, insulin sensitivity, and other hormones related to energy homeostasis. These metabolic changes in turn might also affect dopaminergic activity to influence food motivation and intake of HP foods. An integrative heuristic model is proposed, wherein repeated high levels of stress alter the biology of stress and appetite/energy regulation, with both components directly affecting neural mechanisms contributing to stress-induced and food cue-induced HP food motivation and engagement in overeating of such foods to enhance risk of weight gain and obesity. Future directions in research are identified to increase understanding of the mechanisms by which stress might increase risk of weight gain and obesity. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  6. [Appraisal of occupational stress and its influential factors in nurses].

    Science.gov (United States)

    Yang, Xin-wei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia

    2004-04-01

    To assess the occupational stress and its influential factors in nurses. A test of occupational stress, its influential factors, work ability were carried out for 248 nurses and 319 controls with revised occupational stress inventory (OSI-R) and work ability index (WAI). The scores of personal cope resource (131.266 +/- 17.176) and work ability index (32.581 +/- 3.158) in nurse group were significantly higher than those in control group (126.931 +/- 19.108, 31.840 +/- 4.069) (P < 0.05). The main occupational stressors scores (role insufficiency, role clash, and responsibility) in nurses were higher than those in controls (P < 0.05). The stress response of interpersonal relationship in nurses was also higher. The items of personal cope resource, such as recreation, self-care and social support of nurses were superior to those of controls (P < 0.05). Stress response was positively correlated with occupational role (r = 0.512, P < 0.01), and negatively correlated with the personal cope resource (r = -0.475, P < 0.01). The primary influential factors of personal stress were recreation, social support, rational conduct, role insufficiency, role clash, responsibility, and poor work environment. To strengthen social support, to improve work condition for nurses, so as to reduce the occupational stress and to enhance the work ability of nurses are important task in occupational health field.

  7. Social factors modulate restraint stress induced hyperthermia in mice.

    Science.gov (United States)

    Watanabe, Shigeru

    2015-10-22

    Stress-induced hyperthermia (SIH) was examined in three different social conditions in mice by thermographic measurement of the body surface temperature. Placing animals in cylindrical holders induced restraint stress. I examined the effect of the social factors in SIH using the thermograph (body surface temperature). Mice restrained in the holders alone showed SIH. Mice restrained in the holders at the same time as other similarly restrained cage mates (social equality condition) showed less hyperthermia. Interestingly, restrained mice with free moving cage mates (social inequality condition) showed the highest hyperthermia. These results are consistent with a previous experiment measuring the memory-enhancing effects of stress and the stress-induced elevation of corticosterone, and suggest that social inequality enhances stress. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Response of Desulfovibrio vulgaris to Alkaline Stress

    Energy Technology Data Exchange (ETDEWEB)

    Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D.; Huang, K.; Alm, E.; Hazen, T.C.; Zhou, J.; Wall, J.D.; Arkin, A.P.; Stahl, D.A.

    2007-11-30

    The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included three ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).

  9. Spectra of coset sigma models

    Energy Technology Data Exchange (ETDEWEB)

    Candu, Constantin [Institut fuer Theoretische Physik, Zuerich (Switzerland); Mitev, Vladimir [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Mathematik; Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group

    2013-08-15

    We compute the complete 1-loop spectrum of anomalous dimensions for the bulk fields of non-linear sigma models on symmetric coset (super)spaces G/H, both with and without world-sheet supersymmetry. In addition, we provide two new methods for the construction of partition functions in the infinite radius limit and demonstrate their efficiency in the case of (super)sphere sigma models. Our results apply to a large number of target spaces including superspheres and superprojective spaces such as the N=2 sigma model on CP{sup 3} {sup vertical} {sup stroke} {sup 4}.

  10. Six sigma for revenue retrieval.

    Science.gov (United States)

    Plonien, Cynthia

    2013-01-01

    Deficiencies in revenue retrieval due to failures in obtaining charges have contributed to a negative bottom line for numerous hospitals. Improving documentation practices through a Six Sigma process improvement initiative can minimize opportunities for errors through reviews and instill structure for compliance and consistency. Commitment to the Six Sigma principles with continuous monitoring of outcomes and constant communication of results to departments, management, and payers is a strong approach to reducing the financial impact of denials on an organization's revenues and expenses. Using Six Sigma tools can help improve the organization's financial performance not only for today, but also for health care's uncertain future.

  11. Spectra of coset sigma models

    International Nuclear Information System (INIS)

    Candu, Constantin; Mitev, Vladimir; Humboldt-Universitaet, Berlin; Schomerus, Volker

    2013-08-01

    We compute the complete 1-loop spectrum of anomalous dimensions for the bulk fields of non-linear sigma models on symmetric coset (super)spaces G/H, both with and without world-sheet supersymmetry. In addition, we provide two new methods for the construction of partition functions in the infinite radius limit and demonstrate their efficiency in the case of (super)sphere sigma models. Our results apply to a large number of target spaces including superspheres and superprojective spaces such as the N=2 sigma model on CP 3 vertical stroke 4 .

  12. Impacts on silkworm larvae midgut proteomics by transgenic Trichoderma strain and analysis of glutathione S-transferase sigma 2 gene essential for anti-stress response of silkworm larvae.

    Science.gov (United States)

    Li, Yingying; Dou, Kai; Gao, Shigang; Sun, Jianan; Wang, Meng; Fu, Kehe; Yu, Chuanjin; Wu, Qiong; Li, Yaqian; Chen, Jie

    2015-08-03

    Lepidoptera is a large order of insects that have major impacts on humans as agriculture pests. The midgut is considered an important target for insect control. In the present study, 10 up-regulated, 18 down-regulated, and one newly emerged protein were identified in the transgenic Trichoderma-treated midgut proteome. Proteins related to stress response, biosynthetic process, and metabolism process were further characterized through quantitative real-time PCR (qPCR). Of all the identified proteins, the glutathione S-transferase sigma 2 (GSTs2) gene displayed enhanced expression when larvae were fed with Trichoderma wild-type or transgenic strains. Down regulation of GSTs2 expression by RNA interference (RNAi) resulted in inhibition of silkworm growth when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. Weight per larva decreased by 18.2%, 11.9%, and 10.7% in the untreated control, ddH2O, and GFP dsRNA groups, respectively, at 24h, while the weight decrease was higher at 42.4%, 28.8% and 32.4% at 72 h after treatment. Expression of glutathione S-transferase omega 2 (GSTo2) was also enhanced when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. These results indicated that there was indeed correlation between enhanced expression of GSTs2 and the anti-stress response of silkworm larvae against Trichoderma. This study represents the first attempt at understanding the effects of transgenic organisms on the midgut proteomic changes in silkworm larvae. Our findings could not only broaden the biological control targets of insect at the molecular level, but also provide a theoretical foundation for biological safety evaluation of the transgenic Trichoderma strain. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. [The role of environmental factors in managing labour stress].

    Science.gov (United States)

    Rados, Melinda; Mészáros, Judit

    2017-07-01

    Emotional, cognitive and behavioural aspects of birth and labour stress are strongly associated with the underlying physiological processes. To study the factors of physical security and social support, the administration of synthetic oxytocin, and how they relate to perceived stress during childbirth. Women's experienced physical security, social support and oxytocin administration was measured with targeted questions, and their perceived stress with the short and modified version of the Perceived Stress Scale. A strong negative association was found between perceived stress and physical and social security. The group of women experiencing low physical and social security perceived significantly higher stress, while those given synthetic oxytocin perceived higher stress, and lower physical and social security. Since physiological, psychological processes and behaviours are strongly intertwined, the support of natural physiological birth without interventions is recommended, which considers not only short-term but long-term health consequences for mother and child. The contribution of calming physical surroundings, minimal interventions and empowering support of caregivers to safe and satisfying birth is demonstrated in a model. Orv Hetil. 2017; 158(29): 1149-1156.

  14. Running Head: Implementing Six Sigma Efforts

    Science.gov (United States)

    Lindsay, Jamie Eleaitia Mae

    2005-01-01

    Six Sigma is an organization wide program that provides common set of goals, language, and methodology for improving the overall quality of the processes within the organization (Davis & Heineke 2004). Six Sigma main concern is for the customer. What will the customers want? Need? Six Sigma has a model that helps Sigma get implemented DMAIC model…

  15. Complex regulation of AprA metalloprotease in Pseudomonas fluorescens M114: evidence for the involvement of iron, the ECF sigma factor, PbrA and pseudobactin M114 siderophore.

    Science.gov (United States)

    Maunsell, Bláithín; Adams, Claire; O'Gara, Fergal

    2006-01-01

    In the soil bacterium Pseudomonas fluorescens M114, extracellular proteolytic activity and fluorescent siderophore (pseudobactin M114) production were previously shown to be co-ordinately negatively regulated in response to environmental iron levels. An iron-starvation extracytoplasmic function sigma factor, PbrA, required for the transcription of siderophore biosynthetic genes, was also implicated in M114 protease regulation. The current study centred on the characterization and genetic regulation of the gene(s) responsible for protease production in M114. A serralysin-type metalloprotease gene, aprA, was identified and found to encode the major, if not only, extracellular protease produced by this strain. The expression of aprA and its protein product were found to be subject to complex regulation. Transcription analysis confirmed that PbrA was required for full aprA transcription under low iron conditions, while the ferric uptake regulator, Fur, was implicated in aprA repression under high iron conditions. Interestingly, the iron regulation of AprA was dependent on culture conditions, with PbrA-independent AprA-mediated proteolytic activity observed on skim milk agar supplemented with yeast extract, when supplied with iron or purified pseudobactin M114. These effects were not observed on skim milk agar without yeast extract. PbrA-independent aprA expression was also observed from a truncated transcriptional fusion when grown in sucrose asparagine tryptone broth supplied with iron or purified pseudobactin M114. Thus, experimental evidence suggested that iron mediated its effects via transcriptional activation by PbrA under low iron conditions, while an as-yet-unidentified sigma factor(s) may be required for the PbrA-independent aprA expression and AprA proteolytic activity induced by siderophore and iron.

  16. Risk factors for stress in children after parental stroke

    NARCIS (Netherlands)

    Sieh, D.S.; Meijer, A.M.; Visser-Meily, J.M.

    2010-01-01

    Objectives: To assess risk factors for stress in children 3 years after parental stroke. Participants: Questionnaires were filled in by 44 children aged 7-18 years, parents who suffered a stroke and healthy spouses from 29 families recruited in 9 participating rehabilitation centers across the

  17. Factors Affecting Role Stress and Burnout among School Counselors

    Science.gov (United States)

    Willingham, Wendy Elizabeth

    2009-01-01

    The purpose of this study is to determine factors affecting role stress and burnout among practicing school counselors as measured by the Maslach Burnout Inventory-Educators Survey (MBI-ES) and the Role Conflict and Ambiguity Scale. The MBI-ES utilizes three subscales to measure burnout: emotional exhaustion, depersonalization, and personal…

  18. Factors Influencing Stress, Burnout, and Retention of Secondary Teachers

    Science.gov (United States)

    Fisher, Molly H.

    2011-01-01

    This study examines the stress, burnout, satisfaction, and preventive coping skills of nearly 400 secondary teachers to determine variables contributing to these major factors influencing teachers. Analysis of Variance (ANOVA) statistics were conducted that found the burnout levels between new and experienced teachers are significantly different,…

  19. Risk factors for antenatal depression, postnatal depression and parenting stress

    Directory of Open Access Journals (Sweden)

    Milgrom Jeannette

    2008-04-01

    Full Text Available Abstract Background Given that the prevalence of antenatal and postnatal depression is high, with estimates around 13%, and the consequences serious, efforts have been made to identify risk factors to assist in prevention, identification and treatment. Most risk factors associated with postnatal depression have been well researched, whereas predictors of antenatal depression have been less researched. Risk factors associated with early parenting stress have not been widely researched, despite the strong link with depression. The aim of this study was to further elucidate which of some previously identified risk factors are most predictive of three outcome measures: antenatal depression, postnatal depression and parenting stress and to examine the relationship between them. Methods Primipara and multiparae women were recruited antenatally from two major hoitals as part of the beyondblue National Postnatal Depression Program 1. In this subsidiary study, 367 women completed an additional large battery of validated questionnaires to identify risk factors in the antenatal period at 26–32 weeks gestation. A subsample of these women (N = 161 also completed questionnaires at 10–12 weeks postnatally. Depression level was measured by the Beck Depression Inventory (BDI. Results Regression analyses identified significant risk factors for the three outcome measures. (1. Significant predictors for antenatal depression: low self-esteem, antenatal anxiety, low social support, negative cognitive style, major life events, low income and history of abuse. (2. Significant predictors for postnatal depression: antenatal depression and a history of depression while also controlling for concurrent parenting stress, which was a significant variable. Antenatal depression was identified as a mediator between seven of the risk factors and postnatal depression. (3. Postnatal depression was the only significant predictor for parenting stress and also acted as a mediator

  20. Risk factors for antenatal depression, postnatal depression and parenting stress.

    Science.gov (United States)

    Leigh, Bronwyn; Milgrom, Jeannette

    2008-04-16

    Given that the prevalence of antenatal and postnatal depression is high, with estimates around 13%, and the consequences serious, efforts have been made to identify risk factors to assist in prevention, identification and treatment. Most risk factors associated with postnatal depression have been well researched, whereas predictors of antenatal depression have been less researched. Risk factors associated with early parenting stress have not been widely researched, despite the strong link with depression. The aim of this study was to further elucidate which of some previously identified risk factors are most predictive of three outcome measures: antenatal depression, postnatal depression and parenting stress and to examine the relationship between them. Primipara and multiparae women were recruited antenatally from two major hoitals as part of the beyondblue National Postnatal Depression Program 1. In this subsidiary study, 367 women completed an additional large battery of validated questionnaires to identify risk factors in the antenatal period at 26-32 weeks gestation. A subsample of these women (N = 161) also completed questionnaires at 10-12 weeks postnatally. Depression level was measured by the Beck Depression Inventory (BDI). Regression analyses identified significant risk factors for the three outcome measures. (1). Significant predictors for antenatal depression: low self-esteem, antenatal anxiety, low social support, negative cognitive style, major life events, low income and history of abuse. (2). Significant predictors for postnatal depression: antenatal depression and a history of depression while also controlling for concurrent parenting stress, which was a significant variable. Antenatal depression was identified as a mediator between seven of the risk factors and postnatal depression. (3). Postnatal depression was the only significant predictor for parenting stress and also acted as a mediator for other risk factors. Risk factor profiles for

  1. NAC Transcription Factors in Stress Responses and Senescence

    DEFF Research Database (Denmark)

    O'Shea, Charlotte

    Plant-specific NAM/ATAF/CUC (NAC) transcription factors have recently received considerable attention due to their significant roles in plant development and stress signalling. This interest has resulted in a number of physiological, genetic and cell biological studies of their functions. Some...... of these studies have also revealed emerging gene regulatory networks and protein-protein interaction networks. However, structural studies relating structure to function are lagging behind. Structure-function analysis of the NAC transcription factors has therefore been the main focus of this PhD thesis...... not involve significant folding-upon-binding but fuzziness or an extended ANAC046 region. The ANAC046 regulatory domain functions as an entropic chain with a bait for interactions with for example RCD1. RCD1 interacts with transcription factors from several different families, and the large stress...

  2. Stress concentration factors for pressurized elliptic crossbores in blocks

    International Nuclear Information System (INIS)

    Badr, Elie A.

    2006-01-01

    Intersecting bore geometries are used in a number of industrial applications including heavy-walled pressure vessels containing oil holes for lubrication, ports for valves and fluid ends of reciprocating pumps. The bore intersection location is a stress concentration point where the maximum hoop stress can be many times the fluid pressure in the bores. Intersecting circular holes in heavy-walled cylinders and rectangular blocks have been extensively investigated. Specifically, stress/pressure concentration curves for intersecting circular bores in rectangular blocks were presented by Sorem et al. [Sorem JR, Shadley JR, Tipton SM. Design curves for maximum stresses in blocks containing pressurized bore intersections. ASME J Mech Des 1990; 113: 427-31.]. However, stress/pressure concentrations due to intersecting elliptic bores have not been broadly investigated. With the availability of computer numerical control (CNC) machinery, bores with elliptic crosssection can be produced with relative ease. In this paper, hoop stress concentration ratios are developed for elliptic crossbores in rectangular blocks. Results indicate that introducing elliptic crossbores, rather than circular ones, significantly reduces the hoop stress concentration factor at the crossbore intersection. Also, the presence of intersecting crossbores has a major effect on the fatigue life of pressure vessels [Badr EA, Sorem JR, Jr Tipton SM. Evaluation of the autofrettage effect on fatigue lives of steel blocks with crossbores using a statistical and a strain-based method. ASTM J Test Eval 2000; 28: 181-8.] and the reduction of hoop stress concentration is expected to enhance the fatigue life of pressure vessels containing crossbores

  3. Rib-pillar mining at Sigma Colliery

    Energy Technology Data Exchange (ETDEWEB)

    De Beer, J J.S.; Hunter, F; Neethling, A F [Sigma Colliery, Sasolburg (South Africa)

    1991-06-01

    The paper describes the rib-pillar extraction method now used at Sigma Colliery in the Orange Free State. In this method, access roadways (with a high safety factor) are developed into a block of coal suitable for total extraction; pillars that have a low safety factor are then formed and extracted immediately. The method, together with the current practices of labour management, has resulted in better utilization of the coal resources and capital, increased production and labour productivity, and improved safety. 11 figs.

  4. Transient thermal stresses and stress intensity factors induced by thermal stratification in feedwater lines

    International Nuclear Information System (INIS)

    Sanchez Sarmiento, G.; Pardo, E.

    1985-01-01

    General analytical solutions for the thermal stresses and circumferential crack propagation in piping branches of nuclear power plants, that connect two circuits of the same fluid at different temperatures, are presented in this paper. Under certain conditions, two regions of the fluid possessing both temperatures with a separating layer of small thickness are formed ('flow stratification'). Dimensionless analytical expressions for the steady state temperature distribution in the pipe wall and the corresponding thermal stress are here derived, in terms of the basic geometrical and physical parameters. The position and thickness of the separating layer are considered as data of the model. Stress intensity ranges at any point of the tube wall are then determined. Finally, thermally induced stress intensity factors are calculated for hipothetically inside surface cracks. (orig.)

  5. An application of Six Sigma methodology to turnover intentions in health care.

    Science.gov (United States)

    Taner, Mehmet

    2009-01-01

    The purpose of this study is to show how the principles of Six Sigma can be applied to the high turnover problem of doctors in medical emergency services and paramedic backup. Six Sigma's define-measure-analyse-improve-control (DMAIC) is applied for reducing the turnover rate of doctors in an organisation operating in emergency services. Variables of the model are determined. Explanatory factor analysis, multiple regression, analysis of variance (ANOVA) and Gage R&R are employed for the analysis. Personal burnout/stress and dissatisfaction from salary were found to be the "vital few" variables. The organisation took a new approach by improving its initiatives to doctors' working conditions. Sigma level of the process is increased. New policy and process changes have been found to effectively decrease the incidence of turnover intentions. The improved process is gained, standardised and institutionalised. This study is one of the few papers in the literature that elaborates the turnover problem of doctors working in the emergency and paramedic backup services.

  6. Modified stress intensity factor as a crack growth parameter applicable under large scale yielding conditions

    International Nuclear Information System (INIS)

    Yasuoka, Tetsuo; Mizutani, Yoshihiro; Todoroki, Akira

    2014-01-01

    High-temperature water stress corrosion cracking has high tensile stress sensitivity, and its growth rate has been evaluated using the stress intensity factor, which is a linear fracture mechanics parameter. Stress corrosion cracking mainly occurs and propagates around welded metals or heat-affected zones. These regions have complex residual stress distributions and yield strength distributions because of input heat effects. The authors previously reported that the stress intensity factor becomes inapplicable when steep residual stress distributions or yield strength distributions occur along the crack propagation path, because small-scale yielding conditions deviate around those distributions. Here, when the stress intensity factor is modified by considering these distributions, the modified stress intensity factor may be used for crack growth evaluation for large-scale yielding. The authors previously proposed a modified stress intensity factor incorporating the stress distribution or yield strength distribution in front of the crack using the rate of change of stress intensity factor and yield strength. However, the applicable range of modified stress intensity factor for large-scale yielding was not clarified. In this study, the range was analytically investigated by comparison with the J-integral solution. A three-point bending specimen with parallel surface crack was adopted as the analytical model and the stress intensity factor, modified stress intensity factor and equivalent stress intensity factor derived from the J-integral were calculated and compared under large-scale yielding conditions. The modified stress intensity was closer to the equivalent stress intensity factor when compared with the stress intensity factor. If deviation from the J-integral solution is acceptable up to 2%, the modified stress intensity factor is applicable up to 30% of the J-integral limit, while the stress intensity factor is applicable up to 10%. These results showed that

  7. Posttraumatic stress disorder in bosnian war veterans: Analysis of stress events and risk factors

    Directory of Open Access Journals (Sweden)

    Kuljić Blagoje

    2004-01-01

    Full Text Available The aim of this study was to determine the incidence of Post-Traumatic Stress Disorder (PTSD, the characteristics of stress-related events, and the risk factors for the development of PTSD. The total patient sample consisted of 100 Bosnian war veterans. Watson’s PTSD module was used in establishing PTSD diagnosis. Patients fulfilled the following questionnaires: personal data form, Posttraumatic Symptom Scale PTSS-10 (Holen, Impact of Event Scale (Horowitz, Life Event Scale, and Eysenck Personality Inventory. PTSD was diagnosed in 30% of the examined patients. Larger number of stress-related events, particularly of those regarded as life-threatening, wounding/death of a close person, and material losses were more frequent in persons with PTSD. The risk factors for the development of PTSD in this study were: age (30-40, marital status (married, lower level of education, the front-line combat exposure, neurotic manifestations, family problems in childhood, and neuroticism.

  8. Seis Sigma: Fatores Críticos de Sucesso para sua Implantação

    Directory of Open Access Journals (Sweden)

    Antonio Cesar Amaru Maximiano

    2009-10-01

    Full Text Available This article describes an investigation of critical success factors to implement Six Sigma in organizations operating in the Brazilian market place. Besides that, a secondary objective was to investigate the relationship between aspects like success perception among those companies which implemented Six Sigma, company size, company nationality, time of Six Sigma of implementation, continuous training, communication level between professionals, full-time and part-time Black Belts, project completion, project duration and project savings. Data were collected through an Internet questionnaire, distributed by email and sent to discussion groups involving Six Sigma professionals. Questionnaire development included a literature review and interviews with experienced Six Sigma professionals. The results indicated eight critical success factors for Six Sigma implementation: (a Leadership, (b Projects, (c Training, (d Communication and Review, (e Managerial Process, (f Black Belts Profile, (g Project Teams and (h Previous Quality Initiatives.

  9. Endoplasmic Reticulum Stress-Related Factors Protect against Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Wei-Kun Hu

    2012-01-01

    Full Text Available The endoplasmic reticulum (ER is a principal mediator of signal transduction in the cell, and disruption of its normal function (a mechanism known as ER stress has been associated with the pathogenesis of several diseases. ER stress has been demonstrated to contribute to onset and progression of diabetic retinopathy (DR by induction of multiple inflammatory signaling pathways. Recent studies have begun to describe the gene expression profile of ER stress-related genes in DR; moreover, genes that play a protective role against DR have been identified. P58IPK was determined to be able to reduce retinal vascular leakage under high glucose conditions, thus protecting retinal cells. It has also been found by our lab that ER-associated protein degradation factors exhibit significantly different expression patterns in rat retinas under sustained high glucose conditions. Future research based upon these collective genomic findings will contribute to our overall understanding of DR pathogenesis as well as identify potential therapeutic targets.

  10. Transgenerational Social Stress, Immune Factors, Hormones, and Social Behavior

    Directory of Open Access Journals (Sweden)

    Christopher Anthony Murgatroyd

    2016-01-01

    Full Text Available A social signal transduction theory of depression has been proposed that states that exposure to social adversity alters the immune response and these changes mediate symptoms of depression such as anhedonia and impairments in social behavior. The exposure of maternal rats to the chronic social stress (CSS of a male intruder depresses maternal care and impairs social behavior in the F1 and F2 offspring of these dams. The objective of the present study was to characterize basal peripheral levels of several immune factors and related hormone levels in the adult F2 offspring of CSS exposed dams and assess whether changes in these factors are associated with previously reported deficits in allogrooming behavior. CSS decreased acid glycoprotein (α1AGP and intercellular adhesion molecule-1 (ICAM-1 in F2 females, and increased granulocyte macrophage-colony stimulating factor (GM-CSF in F2 males. There were also sex dependent changes in IL-18, tissue inhibitors of metalloproteinases 1 (TIMP-1, and vascular endothelial growth factor (VEGF. Progesterone was decreased and alpha melanocyte stimulating hormone (α-MSH was increased in F2 males, and brain-derived neurotrophic factor (BDNF was decreased in F2 females. Changes in α1AGP, GM-CSF, progesterone and α-MSH were correlated with decreased allogrooming in the F2 offspring of stressed dams. These results support the hypothesis that transgenerational social stress affects both the immune system and social behavior, and also support previous studies on the adverse effects of early life stress on immune functioning and stress associated immunological disorders, including the increasing prevalence of asthma. The immune system may represent an important transgenerational etiological factor in disorders which involve social and/or early life stress associated changes in social behavior, such as depression, anxiety, and autism, as well as comorbid immune disorders. Future studies involving immune and

  11. Captodiamine, a putative antidepressant, enhances hypothalamic BDNF expression in vivo by synergistic 5-HT2c receptor antagonism and sigma-1 receptor agonism.

    Science.gov (United States)

    Ring, Rebecca M; Regan, Ciaran M

    2013-10-01

    The putative antidepressant captodiamine is a 5-HT2c receptor antagonist and agonist at sigma-1 and D3 dopamine receptors, exerts an anti-immobility action in the forced swim paradigm, and enhances dopamine turnover in the frontal cortex. Captodiamine has also been found to ameliorate stress-induced anhedonia, reduce the associated elevations of hypothalamic corticotrophin-releasing factor (CRF) and restore the reductions in hypothalamic BDNF expression. Here we demonstrate chronic administration of captodiamine to have no significant effect on hypothalamic CRF expression through sigma-1 receptor agonism; however, both sigma-1 receptor agonism or 5-HT2c receptor antagonism were necessary to enhance BDNF expression. Regulation of BDNF expression by captodiamine was associated with increased phosphorylation of transcription factor CREB and mediated through sigma-1 receptor agonism but blocked by 5-HT2c receptor antagonism. The existence of two separate signalling pathways was confirmed by immunolocalisation of each receptor to distinct cell populations in the paraventricular nucleus of the hypothalamus. Increased BDNF induced by captodiamine was also associated with enhanced expression of synapsin, but not PSD-95, suggesting induction of long-term structural plasticity between hypothalamic synapses. These unique features of captodiamine may contribute to its ability to ameliorate stress-induced anhedonia as the hypothalamus plays a prominent role in regulating HPA axis activity.

  12. WRKY transcription factors in plant responses to stresses.

    Science.gov (United States)

    Jiang, Jingjing; Ma, Shenghui; Ye, Nenghui; Jiang, Ming; Cao, Jiashu; Zhang, Jianhua

    2017-02-01

    The WRKY gene family is among the largest families of transcription factors (TFs) in higher plants. By regulating the plant hormone signal transduction pathway, these TFs play critical roles in some plant processes in response to biotic and abiotic stress. Various bodies of research have demonstrated the important biological functions of WRKY TFs in plant response to different kinds of biotic and abiotic stresses and working mechanisms. However, very little summarization has been done to review their research progress. Not just important TFs function in plant response to biotic and abiotic stresses, WRKY also participates in carbohydrate synthesis, senescence, development, and secondary metabolites synthesis. WRKY proteins can bind to W-box (TGACC (A/T)) in the promoter of its target genes and activate or repress the expression of downstream genes to regulate their stress response. Moreover, WRKY proteins can interact with other TFs to regulate plant defensive responses. In the present review, we focus on the structural characteristics of WRKY TFs and the research progress on their functions in plant responses to a variety of stresses. © 2016 Institute of Botany, Chinese Academy of Sciences.

  13. Role of sigma-1 receptors in neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Linda Nguyen

    2015-01-01

    Full Text Available Neurodegenerative diseases with distinct genetic etiologies and pathological phenotypes appear to share common mechanisms of neuronal cellular dysfunction, including excitotoxicity, calcium dysregulation, oxidative damage, ER stress and mitochondrial dysfunction. Glial cells, including microglia and astrocytes, play an increasingly recognized role in both the promotion and prevention of neurodegeneration. Sigma receptors, particularly the sigma-1 receptor subtype, which are expressed in both neurons and glia of multiple regions within the central nervous system, are a unique class of intracellular proteins that can modulate many biological mechanisms associated with neurodegeneration. These receptors therefore represent compelling putative targets for pharmacologically treating neurodegenerative disorders. In this review, we provide an overview of the biological mechanisms frequently associated with neurodegeneration, and discuss how sigma-1 receptors may alter these mechanisms to preserve or restore neuronal function. In addition, we speculate on their therapeutic potential in the treatment of various neurodegenerative disorders.

  14. The SIGMA plants economic behavior

    International Nuclear Information System (INIS)

    Rivarola, Martin E.; Bergallo, Juan E.

    1999-01-01

    In this work, the economical behavior of the Uranium Enrichment Plants, built using the Gaseous Isotopic Separation using Advanced Methods (SIGMA) (Separacion Isotopica Gaseosa por Metodos Avanzados) technology is analyzed. The calculations were made using an integrated computer code, where the cost of each main component of the plant is estimated. The program computes the production cost for several configurations of enrichment cascades, each one corresponding to a production rate. The program also includes a numerical optimizer and it seeks the SIGMA optimal configuration for a given set of design parameters. The present work does not contemplate the model and calculation of the auxiliary system costs. The total amortization cost is obtained by using the cascade capital cost and assuming that the auxiliary system represents a fixed part of the total cost.The results obtained show that the SIGMA technology for Enrichment Uranium Plants could achieve economical competition in a much lower production scale than the conventional Gaseous Diffusion Enrichment Plants. (author)

  15. Link Between Deployment Factors and Parenting Stress in Navy Families

    Science.gov (United States)

    2016-04-11

    5a. CONTRACT NUMBER N/A Families 5b. GRANT NUMBER HT9404-13-1-TS05 5c. PROGRAM ELEMENT NUMBER N/A 6. AUTHOR(S) 5d...Purpose: Many service members today are married, and many also have children; deployments affect all members of the military family . The purpose of this...conducted. Findings: As deployment factors increased, parenting stress increased for fathers in the reintegration period, with a potential mediation

  16. Morale as a Protection Factor against Mission Related Stress

    Science.gov (United States)

    2006-04-01

    Inventory [34]. Morale as a Protection Factor against Mission Related Stress RTO-MP HFM-134 10 - 7 - Inventario de Valoración y Afrontamiento...17-37. [27] Miguel-Tobal, J. J. and Cano Vindel, A. (1986). Inventario de Situaciones y Respuestas de Ansiedad. Madrid: Tea Ediciones. (2ª Edic...Psychology, 56, 2, 267-283. [35] Cano Vindel, A. and Miguel-Tobal, J. J. (1992). Inventario de Valoración y Afrontamiento (IVA). Mimeo: Universidad

  17. Latent Factor Structure of DSM-5 Posttraumatic Stress Disorder

    Science.gov (United States)

    Gentes, Emily; Dennis, Paul A.; Kimbrel, Nathan A.; Kirby, Angela C.; Hair, Lauren P.; Beckham, Jean C.; Calhoun, Patrick S.

    2015-01-01

    The current study examined the latent factor structure of posttraumatic stress disorder (PTSD) based on DSM-5 criteria in a sample of participants (N = 374) recruited for studies on trauma and health. Confirmatory factor analyses (CFA) were used to compare the fit of the previous 3-factor DSM-IV model of PTSD to the 4-factor model specified in DSM-5 as well as to a competing 4-factor “dysphoria” model (Simms, Watson, & Doebbeling, 2002) and a 5-factor (Elhai et al., 2011) model of PTSD. Results indicated that the Elhai 5-factor model (re-experiencing, active avoidance, emotional numbing, dysphoric arousal, anxious arousal) provided the best fit to the data, although substantial support was demonstrated for the DSM-5 4-factor model. Low factor loadings were noted for two of the symptoms in the DSM-5 model (psychogenic amnesia and reckless/self-destructive behavior), which raises questions regarding the adequacy of fit of these symptoms with other core features of the disorder. Overall, the findings from the present research suggest the DSM-5 model of PTSD is a significant improvement over the previous DSM-IV model of PTSD. PMID:26366290

  18. Spectra of conformal sigma models

    International Nuclear Information System (INIS)

    Tlapak, Vaclav

    2015-04-01

    In this thesis the spectra of conformal sigma models defined on (generalized) symmetric spaces are analysed. The spaces where sigma models are conformal without the addition of a Wess-Zumino term are supermanifolds, in other words spaces that include fermionic directions. After a brief review of the general construction of vertex operators and the background field expansion, we compute the diagonal terms of the one-loop anomalous dimensions of sigma models on semi-symmetric spaces. We find that the results are formally identical to the symmetric case. However, unlike for sigma models on symmetric spaces, off diagonal terms that lead to operator mixing are also present. These are not computed here. We then present a detailed analysis of the one-loop spectrum of the supersphere S 3 vertical stroke 2 sigma model as one of the simplest examples. The analysis illustrates the power and simplicity of the construction. We use this data to revisit a duality with the OSP(4 vertical stroke 2) Gross-Neveu model that was proposed by Candu and Saleur. With the help of a recent all-loop result for the anomalous dimension of (1)/(2)BPS operators of Gross-Neveu models, we are able to recover the entire zero-mode spectrum of the supersphere model. We also argue that the sigma model constraints and its equations of motion are implemented correctly in the Gross-Neveu model, including the one-loop data. The duality is further supported by a new all-loop result for the anomalous dimension of the ground states of the sigma model. However, higher-gradient operators cannot be completely recovered. It is possible that this discrepancy is related to a known instability of the sigma model. The instability of sigma models is due to symmetry preserving high-gradient operators that become relevant at arbitrarily small values of the coupling. This feature has been observed long ago in one-loop calculations of the O(N)-vector model and soon been realized to be a generic property of sigma models

  19. Some Practical Issues in the Application of Lean Six Sigma to Service Systems

    Directory of Open Access Journals (Sweden)

    Goh Thong-Ngee

    2014-11-01

    Full Text Available Six Sigma as a quality improvement framework has gained considerable popularity in the past two decades. Its extension Lean Six Sigma has also been embraced by many organizations for improvement of quality and business competitiveness. One important factor for the popularity of Six Sigma and Lean Six Sigma is their potential for improving service systems, in contrast to the conventional perceptions that only manufacturing systems can benefit from statistics-based methodologies. There are however a number of issues related to the nature of service systems that must be resolved before the full benefits of Lean Six Sigma can be realized. In this paper, these issues are discussed from a practical point of view from three angles: analytical, organizational, and personal. Awareness of the existence of such issues, if not the answers to all of them, is a pre-requisite to effective adoption of Lean Six Sigma tools.

  20. Development of guide thimble stress peaking factor calculation methodology

    International Nuclear Information System (INIS)

    Lee, Seong Ki; Jeon, Sang Youn; Kim, Jae Ik; Jeon, Kyeong Lak; Kim, Kyu Tae

    2004-01-01

    The Nuclear Fuel Assembly for light water reactor which provides for 236 fuel rods consists of guide tubes, spacer grids, top/bottom nozzles. The guide tubes form the main structural components in conjunction with the grids, act as the main load carrying members of fuel assembly and serve as a support structure and a guide path for the control element, neutron sources and incore instruments after they are secured to upper and lower end areas. Top/bottom nozzles make the end parts of fuel assembly. And the spacer girds maintain the fuel rod array by providing positive lateral restraint to the fuel rod to the fuel rod but only frictional restraint to axial fuel rod motion. When the fuel assembly is in reactor, the tensional and compressional forces are applied to guide thimble through the top nozzle. The stresses vary with the location of guide thimble on the top nozzle plate since the different flow plate thickness between center and outer areas causes a different flexibility. The relative stress shall be considered during designing this kind of structure. And it is useful to know a coefficient to represent this relative stress difference and this value is called stress peaking factor

  1. The C-Terminal RpoN Domain of sigma54 Forms an unpredictedHelix-Turn-Helix Motif Similar to domains of sigma70

    Energy Technology Data Exchange (ETDEWEB)

    Doucleff, Michaeleen; Malak, Lawrence T.; Pelton, Jeffrey G.; Wemmer, David E.

    2005-11-01

    The ''{delta}'' subunit of prokaryotic RNA-polymerase allows gene-specific transcription initiation. Two {sigma} families have been identified, {sigma}{sup 70} and {sigma}{sup 54}, which use distinct mechanisms to initiate transcription and share no detectable sequence homology. Although the {sigma}{sup 70}-type factors have been well characterized structurally by x-ray crystallography, no high-resolution structural information is available for the {sigma}{sup 54}-type factors. Here we present the NMR derived structure of the C-terminal domain of {sigma}{sup 54} from Aquifex aeolicus. This domain (Thr323 to Gly389), which contains the highly conserved RpoN box sequence, consists of a poorly structured N-terminal tail followed by a three-helix bundle, which is surprisingly similar to domains of the {sigma}{sup 70}-type proteins. Residues of the RpoN box, which have previously been shown to be critical for DNA binding, form the second helix of an unpredicted helix-turn-helix motif. This structure's homology with other DNA binding proteins, combined with previous biochemical data, suggest how the C-terminal domain of {sigma}{sup 54} binds to DNA.

  2. The pseudo-scalar form factor of the nucleon, the sigma-like term, and the L0+ amplitude for charged pion electro-production near threshold

    International Nuclear Information System (INIS)

    Cheoun, Myung Ki; Kim, K.S.

    2007-01-01

    The pseudo-scalar form factor, which represents the pseudo-scalar quark density distribution due to finite quark masses on the nucleon, is shown to manifest itself with the induced pseudo-scalar form factor in the L 0 + amplitude for the charged pion electro-production. Both form factors show their own peculiar momentum dependence. Under the approximation on which the Goldberger-Treiman relation holds, a sum of both form factors' contributions accounts for the t-channel contribution in the charged pion electro-production near threshold

  3. Measuring emittances and sigma matrices

    International Nuclear Information System (INIS)

    Rees, J.; Rivkin, L.

    1984-03-01

    The method used for measuring emittance at the SLAC Linac and the linear collider damping ring is described. The basis of the method is derived using one two-by-two matrix to specify the state of the input beam (sigma matrix) and another to describe the lens-drift transport system (R-matrix)

  4. Six Sigma in healthcare delivery.

    Science.gov (United States)

    Liberatore, Matthew J

    2013-01-01

    The purpose of this paper is to conduct a comprehensive review and assessment of the extant Six Sigma healthcare literature, focusing on: application, process changes initiated and outcomes, including improvements in process metrics, cost and revenue. Data were obtained from an extensive literature search. Healthcare Six Sigma applications were categorized by functional area and department, key process metric, cost savings and revenue generation (if any) and other key implementation characteristics. Several inpatient care areas have seen most applications, including admission, discharge, medication administration, operating room (OR), cardiac and intensive care. About 42.1 percent of the applications have error rate as their driving metric, with the remainder focusing on process time (38 percent) and productivity (18.9 percent). While 67 percent had initial improvement in the key process metric, only 10 percent reported sustained improvement. Only 28 percent reported cost savings and 8 percent offered revenue enhancement. These results do not favorably assess Six Sigma's overall effectiveness and the value it offers healthcare. Results are based on reported applications. Future research can include directly surveying healthcare organizations to provide additional data for assessment. Future application should emphasize obtaining improvements that lead to significant and sustainable value. Healthcare staff can use the results to target promising areas. This article comprehensively assesses Six Sigma healthcare applications and impact.

  5. Small-Molecule Sigma1 Modulator Induces Autophagic Degradation of PD-L1.

    Science.gov (United States)

    Maher, Christina M; Thomas, Jeffrey D; Haas, Derick A; Longen, Charles G; Oyer, Halley M; Tong, Jane Y; Kim, Felix J

    2018-02-01

    Emerging evidence suggests that Sigma1 ( SIGMAR1 , also known as sigma-1 receptor) is a unique ligand-regulated integral membrane scaffolding protein that contributes to cellular protein and lipid homeostasis. Previously, we demonstrated that some small-molecule modulators of Sigma1 alter endoplasmic reticulum (ER)-associated protein homeostasis pathways in cancer cells, including the unfolded protein response and autophagy. Programmed death-ligand 1 (PD-L1) is a type I integral membrane glycoprotein that is cotranslationally inserted into the ER and is processed and transported through the secretory pathway. Once at the surface of cancer cells, PD-L1 acts as a T-cell inhibitory checkpoint molecule and suppresses antitumor immunity. Here, we demonstrate that in Sigma1-expressing triple-negative breast and androgen-independent prostate cancer cells, PD-L1 protein levels were suppressed by RNAi knockdown of Sigma1 and by small-molecule inhibition of Sigma1. Sigma1-mediated action was confirmed by pharmacologic competition between Sigma1-selective inhibitor and activator ligands. When administered alone, the Sigma1 inhibitor decreased cell surface PD-L1 expression and suppressed functional interaction of PD-1 and PD-L1 in a coculture of T cells and cancer cells. Conversely, the Sigma1 activator increased PD-L1 cell surface expression, demonstrating the ability to positively and negatively modulate Sigma1 associated PD-L1 processing. We discovered that the Sigma1 inhibitor induced degradation of PD-L1 via autophagy, by a mechanism distinct from bulk macroautophagy or general ER stress-associated autophagy. Finally, the Sigma1 inhibitor suppressed IFNγ-induced PD-L1. Our data demonstrate that small-molecule Sigma1 modulators can be used to regulate PD-L1 in cancer cells and trigger its degradation by selective autophagy. Implications: Sigma1 modulators sequester and eliminate PD-L1 by autophagy, thus preventing functional PD-L1 expression at the cell surface. This

  6. Work Stress as a Risk Factor for Cardiovascular Disease.

    Science.gov (United States)

    Kivimäki, Mika; Kawachi, Ichiro

    2015-09-01

    The role of psychosocial work stress as a risk factor for chronic disease has been the subject of considerable debate. Many researchers argue in support of a causal connection while others remain skeptical and have argued that the effect on specific health conditions is either negligible or confounded. This review of evidence from over 600,000 men and women from 27 cohort studies in Europe, the USA and Japan suggests that work stressors, such as job strain and long working hours, are associated with a moderately elevated risk of incident coronary heart disease and stroke. The excess risk for exposed individuals is 10-40 % compared with those free of such stressors. Differences between men and women, younger versus older employees and workers from different socioeconomic backgrounds appear to be small, indicating that the association is robust. Meta-analyses of a wider range of health outcomes show additionally an association between work stress and type 2 diabetes, though not with common cancers or chronic obstructive pulmonary disease, suggesting outcome specificity. Few studies have addressed whether mitigation of work stressors would reduce the risk of cardiovascular disease. In view of the limited interventional evidence on benefits, harms and cost-effectiveness, definitive recommendations have not been made (e.g. by the US Preventive Services Taskforce) for the primary prevention of cardiovascular disease via workplace stress reduction. Nevertheless, governments are already launching healthy workplace campaigns, and preventing excessive work stress is a legal obligation in several countries. Promoting awareness of the link between stress and health among both employers and workers is an important component of workplace health promotion.

  7. Lean Six Sigma in financial services

    NARCIS (Netherlands)

    de Koning, H.; Does, R.J.M.M.; Bisgaard, S.

    2008-01-01

    Lean Thinking and Six Sigma are typically considered as separate approaches to process innovation, with complementary strengths. When combined as Lean Six Sigma, this approach provides a unified framework for systematically developing innovations. Lean Six Sigma can also bring about significant

  8. Comparative Analysis between Lean, Six Sigma and Lean Six Sigma Concepts

    OpenAIRE

    Alexandra Mirela Cristina MUNTEANU

    2017-01-01

    This paper analyzes the benefits of Lean Six Sigma in comparison with Lean and Six Sigma, traditional improvement methodologies. The introduction highlights the appearance of Lean Six Sigma, early 2000s, as well as the benefits brought by the integrated approach. The following parts of the study emphasize the main differences between methodologies and their commonalities based on their synergy. Finally the advantages of Lean Six Sigma versus Lean and Six Sigma are analyzed and systematized by...

  9. Solution structure of domain 1.1 of the sigma(A) factor from Bacillus subtilis is preformed for binding to the RNA polymerase core

    Czech Academy of Sciences Publication Activity Database

    Zachrdla, M.; Padrta, P.; Rabatinová, Alžběta; Šanderová, Hana; Barvík, I.; Krásný, Libor; Žídek, L.

    2017-01-01

    Roč. 292, č. 28 (2017), s. 11610-11617 ISSN 0021-9258 R&D Projects: GA ČR GA13-16842S; GA MŠk(CZ) LQ1601 Institutional support: RVO:61388971 Keywords : Bacillus * molecular modeling * nuclear magnetic resonance (NMR) Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.125, year: 2016

  10. Activation of sigma-1 receptor chaperone in the treatment of neuropsychiatric diseases and its clinical implication

    Directory of Open Access Journals (Sweden)

    Kenji Hashimoto

    2015-01-01

    Full Text Available Endoplasmic reticulum (ER protein sigma-1 receptor represents unique chaperone activity in the central nervous system, and it exerts a potent influence on a number of neurotransmitter systems. Several lines of evidence suggest that activation of sigma-1 receptor plays a role in the pathophysiology of neuropsychiatric diseases, as well as in the mechanisms of some therapeutic drugs and neurosteroids. Preclinical studies showed that some selective serotonin reuptake inhibitors (SSRIs; fluvoxamine, fluoxetine, excitalopram, donepezil, and ifenprodil act as sigma-1 receptor agonists. Furthermore, sigma-1 receptor agonists could improve the N-methyl-D-aspartate (NMDA antagonist phencyclidine (PCP-induced cognitive deficits in mice. A study using positron emission tomography have demonstrated that an oral administration of fluvoxamine or donepezil could bind to sigma-1 receptor in the healthy human brain, suggesting that sigma-1 receptor might be involved in the therapeutic mechanisms of these drugs. Moreover, case reports suggest that sigma-1 receptor agonists, including fluvoxamine, and ifenprodil, may be effective in the treatment of cognitive impairment in schizophrenia, delirium in elderly people, and flashbacks in post-traumatic stress disorder. In this review article, the author would like to discuss the clinical implication of sigma-1 receptor agonists, including endogenous neurosteroids, in the neuropsychiatric diseases.

  11. Hadron properties in chiral sigma model

    International Nuclear Information System (INIS)

    Shen Hong

    2005-01-01

    The modification of hadron masses in nuclear medium is studied by using the chiral sigma model, which is extended to generate the omega meson mass by the sigma condensation in the vacuum in the same way as the nucleon mass. The chiral sigma model provides proper equilibrium properties of nuclear matter. It is shown that the effective masses of both nucleons and omega mesons decrease in nuclear medium, while the effective mass of sigma mesons increases oat finite density in the chiral sigma model. The results obtained in the chiral sigma model are compared with those obtained in the Walecka model, which includes sigma and omega mesons in a non-chiral fashion. (author)

  12. Job stress and cardiovascular risk factors in male workers.

    Science.gov (United States)

    Kang, Myung Gun; Koh, Sang Baek; Cha, Bong Suk; Park, Jong Ku; Baik, Soon Koo; Chang, Sei Jin

    2005-05-01

    This study examined whether job stress (work demand and decision latitude) is associated with smoking, blood pressure, lipid level (total cholesterol, triglyceride, HDL cholesterol), and homocystein as risk factors for cardiovascular disease in Korean male workers. Study subjects of this study were recruited from a sample of 1,071 workers in 20 companies of W city and H counties, and they were grouped into four categories (high strain group, active group, passive group, and low strain group) based on the postulation of Karasek's Job Strain Model. Of them, we invited 160 male workers (40 people each subgroup) using a stratified sampling, and finally, 152 eligible participants were analyzed. In multivariate analyses, we found that decision latitude was associated with cholesterol, triglyceride, and homocystein and that work demand was related to smoking and systolic blood pressure. Job strain (the combination of high work demand with low decision latitude) was significantly related to higher levels of homocystein after controlling for age, BMI, smoking, and social support at workplace. These results indicate that job stress is associated with cardiovascular risk factors and might contribute to the development of cardiovascular disease. Some considerations for the future research were discussed.

  13. IMPACT OF STRESS FACTORS ON OPTICAL ISOMERISM OF BENAZEPRIL HYDROCHLORIDE.

    Science.gov (United States)

    Kublin, Elżbieta; Czerwińska, Krystyna; Wyszomirska, Elżbieta; Zajaczkowską, Anna; Malanowicz, Ewa; Kaczmarska-Graczyk, Barbara; Mazurek, Aleksander P

    2015-01-01

    Benazepril hydrochloride contains two stereogenic centers, but is currently available as single enantiomer (S,S configuration) for the treatment of hypertension. Its enantiomer (R,R configuration) and the diastereoisomeric pair (R,S and S,R) can be regarded as impurities. Stereochemical stability of S,S isomer of benazepril hydrochloride and its potential susceptibility to conversion in the.active substance and in Lisonid tablets were examinated. The separation with the use of the TLC method with the following system: chromatographic plates Chiralplate and a mobile phase: methanol - acetonitrile - 1 mM copper(II) acetate (4 : 2 : 4, v/v/v) with saturation of glacial acetic acid for 1 h and the HPLC method system: Chiral AGP column (150 x 4.0 man x 5 µm) and a mobile phase: phosphate buffer pH = 6.0 - methanol (80 : 20, v/v) were obtained. Active substance - benazepril hydrochloride and Lisonid tablets 20 mg were subjected to the impact of different stress factors. Samples were examined after 1 and 6 weeks. It was found that none of the applied stress factors caused the transformation of the S,S enantiomer of benazepril hydrochloride in the substance and tablets to other identified stereoisomers - only the compound decomposition has occurred.

  14. The Process to Estimate Economical Benefits of Six Sigma Projects

    Directory of Open Access Journals (Sweden)

    Jan Kosina

    2013-07-01

    Full Text Available This paper seeks to define the process for the continuous evaluation of the financial benefits during Six Sigma project life time. The financial criteria are critical success factors of a Six Sigma project. The process has been developed as part of the six sigma project monitoring in order to estimate proper allocation of the resources taking in account the expected project benefits as well as evaluationof real achievements. The evaluation of the finacial benefits based on the quality costs is not sufficient in the real life and has to be accomplished with key financial performance indicators of the business to visualize the results. The evaluation based on the savings seems to be too difficult especially for green belts. The early involvement of the finance department in the project definition as well as ongoing evaluation is key. The defined process has been applied to real business enviroment.

  15. Introduction to sigma model anomalies

    International Nuclear Information System (INIS)

    Nelson, P.

    1985-01-01

    This paper presents results dealing with the specific case in which a sigma model with fermions arises as a result of dynamical symmetry breakdown from some group G to a subgroup H. H may contain chiral symmetries protecting some fermions in a representation ρ H of H. In this case it may be impossible to quantize the remaining fermions in a way which reproduces the anomalous Ward identities of any underlying strongly-interacting gauge theory. The author concludes that this pattern of symmetry breakdown will not be realized in any such theory. The criterion in this case is local in character, since roughly speaking once the sigma model in question behaves for field configurations close to the vacuum base point in the internal mainfold is known, symmetry can be used to find how it behaves everywhere else

  16. Branes in Poisson sigma models

    International Nuclear Information System (INIS)

    Falceto, Fernando

    2010-01-01

    In this review we discuss possible boundary conditions (branes) for the Poisson sigma model. We show how to carry out the perturbative quantization in the presence of a general pre-Poisson brane and how this is related to the deformation quantization of Poisson structures. We conclude with an open problem: the perturbative quantization of the system when the boundary has several connected components and we use a different pre-Poisson brane in every component.

  17. Lean six sigma in healthcare.

    Science.gov (United States)

    de Koning, Henk; Verver, John P S; van den Heuvel, Jaap; Bisgaard, Soren; Does, Ronald J M M

    2006-01-01

    Healthcare, as with any other service operation, requires systematic innovation efforts to remain competitive, cost efficient, and up-to-date. This article outlines a methodology and presents examples to illustrate how principles of Lean Thinking and Six Sigma can be combined to provide an effective framework for producing systematic innovation efforts in healthcare. Controlling healthcare cost increases, improving quality, and providing better healthcare are some of the benefits of this approach.

  18. Topological sigma models on supermanifolds

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Bei, E-mail: beijia@physics.utexas.edu

    2017-02-15

    This paper concerns constructing topological sigma models governing maps from semirigid super Riemann surfaces to general target supermanifolds. We define both the A model and B model in this general setup by defining suitable BRST operators and physical observables. Using supersymmetric localization, we express correlation functions in these theories as integrals over suitable supermanifolds. In the case of the A model, we obtain an integral over the supermoduli space of “superinstantons”. The language of supergeometry is used extensively throughout this paper.

  19. Polarization-induced sigma-holes and hydrogen bonding

    Czech Academy of Sciences Publication Activity Database

    Hennemann, M.; Murray, J. S.; Politzer, P.; Riley, Kevin Eugene; Clark, T.

    2012-01-01

    Roč. 18, č. 6 (2012), s. 2461-2469 ISSN 1610-2940 Institutional research plan: CEZ:AV0Z40550506 Keywords : hydrogen bond * sigma-hole * polarization * field effect * ab initio calculation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.984, year: 2012

  20. Stress Causing Factors Among Teachers in Elementary Schools and Their Relationship with Demographic and Job Characteristics

    OpenAIRE

    Agai–Demjaha, Teuta; Minov, Jordan; Stoleski, Sasho; Zafirova, Beti

    2015-01-01

    BACKGROUND: Once high levels of work-related stress among teachers were confirmed many studies concentrated on identifying and investigating key stress factors among school teachers. Unfortunately there are very few researches made on stress causing factors among teachers in Republic of Macedonia. AIM: To determine the most frequent stress causing factors among teachers in elementary schools and to investigate their relationship with demographic and job characteristics. METHODOLOGY: W...

  1. Exposing women to workplace stress factors as a risk factor for developing arterial hypertension.

    Science.gov (United States)

    Bojar, Iwona; Humeniuk, Ewa; Owoc, Alfred; Wierzba, Waldemar; Wojtyła, Andrzej

    2011-01-01

    The purpose of this study is the evaluation of women's exposure to stress-inducing factors at work, definition of a scale of the problem, as well as assessment of the impact of professional work on the value of arterial pressure. The research was conducted on four professional groups of women: working in agriculture, working as clerks, seamstresses, as well as those working as medical representative in the period from August- September 2008 in the Lublin region. A total number of 416 women was examined, ages ranging from 30-40, who had not been previously treated due to arterial hypertension. The women under examination had their arterial blood pressure measured twice on a working day at 08:00 and at 14:00. The values of measurements were averaged. The research tool was also the standardised Questionnaire for Subjective Work Evaluation. The raw result was obtained on the basis of summing up all the points, which were afterwards transformed into 10 standard values. The general result was given in 10 standard values, whereas the results of stress factors were quoted as mean results of raw values and were referred to results defined as high for a given factor. The results obtained were statistically analysed on the basis of t-Student test. The significance level adopted was pplace of residence, on the intensification of stress related to a particular factor of work evaluation, was also analysed. Stress experienced by women at a workplace affects not ony their professional life, but also family life and social intercourses. In the women's opinion, an unpleasant workplace is such a workplace where the feeling of mental workload is connected with the lack of rewards (motivation), uncertainty resulting from organisation of daily chores and lack of support from others. The high general level of stress was noted among the group of women working in agriculture, in pharmaceutical companies, as well as among those who perform physical work (seamstresses). The intensification

  2. Intuitive Understanding of sigma Delocalization in Loose and sigma Localization in Tight Helical Conformations of an Oligosilane Chain

    Czech Academy of Sciences Publication Activity Database

    Jovanovic, M.; Antic, D.; Rooklin, D.; Bande, A.; Michl, Josef

    2017-01-01

    Roč. 12, č. 11 (2017), s. 1250-1263 ISSN 1861-4728 Institutional support: RVO:61388963 Keywords : electron delocalization * electron localization * electronic states * oligosilanes * sigma conjugation Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 4.083, year: 2016

  3. Factors Contributing to Perceived Stress among Doctor of Pharmacy (PharmD) Students

    Science.gov (United States)

    Ford, Kentya C.; Olotu, Busuyi S.; Thach, Andrew V.; Roberts, Rochelle; Davis, Patrick

    2014-01-01

    Objective: The purpose of this study was to report on perceived stress levels, identify its contributing factors, and evaluate the association between perceived stress and usage of university resources to cope with stress among a cross-section of Doctor of Pharmacy (PharmD) students. Methods: Perceived stress was measured via a web-based survey of…

  4. Barriers of six sigma in healthcare organizations

    Directory of Open Access Journals (Sweden)

    Serkan Deniz

    2018-09-01

    Full Text Available Six Sigma approach is based on decreasing defects and variations in the products and processes, and it provides important benefits to healthcare organizations. This study aims to identify managers’ opinions, who work in private healthcare organizations, about the reasons behind not using Six Sigma in their organizations. The research was performed between December 2016 and March 2018 in private healthcare organizations (private hospitals and medical centers operating in Turkey and not using Six Sigma approach. Data were collected from managers, who have knowledge about Six Sigma, through using surveys. In this study, survey methodology was used to collect data. According to the results, the biggest barrier related to not using Six Sigma is based on the lack of knowledge about Six Sigma. The other important barrier about the diffusion of Six Sigma within this organizations is related to the lack of support from top management and leaders. Another finding about the reasons of not applying Six Sigma approach is that there is not a statistically significant difference among managers in terms of their managerial position. In order to overcome the lack of knowledge about Six Sigma, it is advised that managers should take steps in the direction of promoting Six Sigma within their current organization, and provide necessary support and leadership about the process.

  5. Effect of Couple Stresses on the Stress Intensity Factors for Two Parallel Cracks in an Infinite Elastic Medium under Tension

    Directory of Open Access Journals (Sweden)

    Shouetsu Itou

    2012-01-01

    Full Text Available Stresses around two parallel cracks of equal length in an infinite elastic medium are evaluated based on the linearized couple-stress theory under uniform tension normal to the cracks. Fourier transformations are used to reduce the boundary conditions with respect to the upper crack to dual integral equations. In order to solve these equations, the differences in the displacements and in the rotation at the upper crack are expanded through a series of functions that are zero valued outside the crack. The unknown coefficients in each series are solved in order to satisfy the boundary conditions inside the crack using the Schmidt method. The stresses are expressed in terms of infinite integrals, and the stress intensity factors can be determined using the characteristics of the integrands for an infinite value of the variable of integration. Numerical calculations are carried out for selected crack configurations, and the effect of the couple stresses on the stress intensity factors is revealed.

  6. Design for six sigma: A review

    Directory of Open Access Journals (Sweden)

    Kouroush Jenab

    2018-01-01

    Full Text Available Six Sigma is recognized as an essential tool for continuous improvement of quality. A large num-ber of publications by various authors reflect the interest in this technique. Reviews of literature on Six Sigma have been done in the past by a few authors. However, considering the contributions in the recent times, a more comprehensive review is attempted here. The authors have examined vari-ous papers and have proposed a different scheme of classification. In addition, certain gaps that would provide hints for further research in Six Sigma have been identified. As a results the rela-tionship between Six Sigma, Design for Six Sigma (DFSS, and how these two concepts support the quality system for organizational learning and innovation performance have been discussed that would help researchers, academicians and practitioners to take a closer look at the growth, devel-opment and applicability of Six Sigma in Design.

  7. [Psychosomatic stress factors in compensated and decompensated tinnitus].

    Science.gov (United States)

    Stobik, Corinna; Weber, Rainer K; Münte, Thomas F; Frommer, Jörg

    2003-08-01

    In modern medical practice, chronic decompensated tinnitus is defined as a complex psychosomatic process in which mental and social factors are considered to have a determining effect on the patient's subjective response to the impairment of otological or other somatic functions attributed to tinnitus. What is still largely unknown is the interaction of the individual factors and their impact on the patient's ability to cope with tinnitus. The impact of psycho-social and somatic factors on the subjective experience of patients with compensated and decompensated tinnitus is evaluated. 53 patients with chronic tinnitus were divided into two groups, compensated and decompensated, on the basis of their subjective experience of the disorder, established according to the tinnitus questionnaire published by Goebel and Hiller. Self-assessment instruments and a survey of symptoms of somatic stress disorders were used to compare the two groups in terms of differences in the patients' mental and psycho-social behaviour, in their strategies for coping with tinnitus and in the incidence of co-morbidity. The patients with decompensated tinnitus suffered from more pronounced mental and social disabilities, were more prone to depression and used less effective techniques to cope with their illness. The principal difference between the two groups, however, appeared to lie in a significantly higher degree of somatic multi-morbidity, where a particularly strong correlation was found between tinnitus and the incidence of cardiovascular diseases and hypacusis. 81 percent of the total sample of patients suffered from impaired hearing. Patients with decompensated tinnitus experienced greater communication difficulties as a result of their auditory impairment. In the diagnosis and therapy of tinnitus, in addition to psychic and psycho-social aspects greater attention ought to be paid to somatic factors, influencing the patient's ability to cope with the disorder.

  8. Determinants of Perceived Stress in Individuals with Obesity: Exploring the Relationship of Potentially Obesity-Related Factors and Perceived Stress

    OpenAIRE

    Florian Junne; Katrin Ziser; Katrin Elisabeth Giel; Kathrin Schag; Eva Skoda; Isabelle Mack; Andreas Niess; Stephan Zipfel; Martin Teufel

    2017-01-01

    Objective: Associations of specific types of stress with increased food intake and subsequent weight gain have been demonstrated in animal models as well as in experimental and epidemiological studies on humans. This study explores the research question of to what extent potentially obesity-related factors determine perceived stress in individuals with obesity. Methods: N = 547 individuals with obesity participated in a cross-sectional study assessing perceived stress as the outcome variable ...

  9. Lean Six Sigma in financial services

    OpenAIRE

    de Koning, H.; Does, R.J.M.M.; Bisgaard, S.

    2008-01-01

    Lean Thinking and Six Sigma are typically considered as separate approaches to process innovation, with complementary strengths. When combined as Lean Six Sigma, this approach provides a unified framework for systematically developing innovations. Lean Six Sigma can also bring about significant results and breakthrough improvements in financial services, as demonstrated with four case studies from Dutch multinational insurance companies. These cases demonstrate the importance of incremental i...

  10. Cohomological reduction of sigma models

    Energy Technology Data Exchange (ETDEWEB)

    Candu, Constantin; Mitev, Vladimir; Schomerus, Volker [DESY, Hamburg (Germany). Theory Group; Creutzig, Thomas [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy

    2010-01-15

    This article studies some features of quantum field theories with internal supersymmetry, focusing mainly on 2-dimensional non-linear sigma models which take values in a coset superspace. It is discussed how BRST operators from the target space super- symmetry algebra can be used to identify subsectors which are often simpler than the original model and may allow for an explicit computation of correlation functions. After an extensive discussion of the general reduction scheme, we present a number of interesting examples, including symmetric superspaces G/G{sup Z{sub 2}} and coset superspaces of the form G/G{sup Z{sub 4}}. (orig.)

  11. Factors Associated with Urinary Stress Incontinence in Primiparas

    Directory of Open Access Journals (Sweden)

    Pei-Ling Chou

    2005-03-01

    Conclusion: For primiparas who underwent vaginal delivery, an increase in age was associated with increased risk of development of stress incontinence. Increased vulnerability of the pelvic floor with age might explain this finding. Pelvic floor exercise had a protective effect against postpartum stress incontinence in primiparas who underwent cesarean section. This reflects the fact that pregnancy per se carries a risk of stress incontinence. We recommend that primiparas perform pelvic floor exercises to prevent the development of postpartum stress incontinence.

  12. Institutional racism, neighborhood factors, stress, and preterm birth.

    Science.gov (United States)

    Mendez, Dara D; Hogan, Vijaya K; Culhane, Jennifer F

    2014-01-01

    Racial/ethnic disparities in the risk of preterm birth may be explained by various factors, and previous studies are limited in examining the role of institutional racism. This study focused on the following questions: what is the association between preterm birth and institutional racism as measured by residential racial segregation (geographic separation by race) and redlining (black-white disparity in mortgage loan denial); and what is the association between preterm birth and reported stress, discrimination, and neighborhood quality. We used data from a clinic-based sample of pregnant women (n = 3462) participating in a stress and pregnancy study conducted from 1999 to 2004 in Philadelphia, PA (USA). We linked data from the 2000 US Census and Home Mortgage Disclosure Act (HMDA) data from 1999 to 2004 and developed measures of residential redlining and segregation. Among the entire population, there was an increased risk for preterm birth among women who were older, unmarried, tobacco users, higher number of previous births, high levels of experiences of everyday discrimination, owned their homes, lived in nonredlined areas, and areas with high levels of segregation measured by the isolation index. Among black women, living in a redlined area (where blacks were more likely to be denied mortgage loans compared to whites) was moderately associated with a decreased risk of preterm birth (aRR = 0.8, 95% CI: 0.6, 0.99). Residential redlining as a form institutional racism and neighborhood characteristic may be important for understanding racial/ethnic disparities in pregnancy and preterm birth.

  13. [Analysis of risk factors about stress urinary incontinence in female].

    Science.gov (United States)

    Song, Yan-feng; Lin, Jian; Li, Ya-qin; He, Xiao-yu; Xu, Bo; Hao, Lan; Song, Jian

    2003-12-01

    The aim was to assess the prevalence of stress urinary incontinence (SUI) in community dwelling women and to assess the relationship between the various risk factors and this disease. Selecting the community of Gulou at random and sending questionnaires to 6,066 women who living there. The questionnaire was designed to investigate the lower urinary tract symptoms, especially urinary incontinence. The questionnaire included some questions such as: age, weight, occupation, the level of education, menopause pregnancy and delivery, delivery through vagina or by cesarean section, the maximum body weight of fetus, chronic disease (hypertension, diabetes mellitus, cough, constipation), operation in abdomen and pelvis, the behaviour of life (smoking, alcohol abuse, exercise), the prevalence and frequency of urinary incontinence, the quality of life and the recognition of this disease. The collecting rate was 92.1% (5,587/6,066). The prevalence of urinary incontinence was 18.1% and the prevalence of SUI was 8.8%. Age (OR: 1.010, 95% CI: 1.001 - 1.025), higher body mass index (OR: 1.092, 95% CI: 1.054 - 1.132), hypertension (OR: 2.342, 95% CI: 1.026 - 5.349), constipation (OR: 1.448, 95% CI: 1.216 - 1.725), multiple abortion (OR: 1.306, 95% CI: 1.113 - 1.533), multipara (OR: 1.205, 95% CI: 1.009 - 1.440), using abdominal pressure in laboring (OR: 1.684, 95% CI: 1.140 - 2.489), straight cutting of perineum (OR: 2.244, 95% CI: 1.162 - 4.334), perineum tear (OR: 2.576, 95% CI: 1.724 - 3.851), infection of perineal incision (OR: 5.988, 95% CI: 1.936 - 18.616) were risk factors of SUI in women. Many risk factors can cause urinary incontinence, among them age, pregnancy and childbirth are most important ones.

  14. Oxidative stress associated with exercise, psychological stress and life-style factors

    DEFF Research Database (Denmark)

    Møller, P; Wallin, H; Knudsen, Lisbeth E.

    1996-01-01

    generation. Here, we review the effect of alcohol, air pollution, cigarette smoke, diet, exercise, non-ionizing radiation (UV and microwaves) and psychological stress on the development of oxidative stress. Regular exercise and carbohydrate-rich diets seem to increase the resistance against oxidative stress....... Air pollution, alcohol, cigarette smoke, non-ionizing radiation and psychological stress seem to increase oxidative stress. Alcohol in lower doses may act as an antioxidant on low density lipoproteins and thereby have an anti-atherosclerotic property....

  15. Stress intensity factors of corner cracks in two nozzle-cylinder intersections

    International Nuclear Information System (INIS)

    Kobayashi, A.S.; Polvanich, N.; Emery, A.F.; Love, W.J.

    1977-01-01

    In a recent paper, the authors presented the stress-intensity-magnification factors of a quarter-elliptical surface crack in a quarter-infinite solid and a circular crack approaching a reentry corner in a three-quarter infinite solid. These stress-intensity-magnification factors were used together with a curvature-correction factor to estimate the stress-intensity factor of a corner crack at a nozzle-cylinder intersection. Through appropriate superposition of the above stress-intensity-magnification factors, stress-intensity factors for hypothetical corner cracks at a nozzle-cylinder intersection subjected to internal pressure and transient thermal-stress loadings can be obtained. A description of a computer code based on this procedure as well as its applications in analyzing two corner-crack problems at a nozzle-cylinder intersection are discussed in this paper

  16. Stress intensity factors of corner cracks in two nozzle-cylinder interactions

    International Nuclear Information System (INIS)

    Kobayashi, A.S.; Polvanich, N.; Emery, A.F.; Love, W.J.

    1977-01-01

    In a recent paper, the authors presented the stress-intensity-magnification factors of a quarter-elliptical surface crack in a quarter-infinite solid and a circular crack approaching a reentry corner in a three-quarter infinite solid. These stress-intensity-magnification factors were used together with a curvature-correction factor to estimate the stress-intensity factor of a corner crack at a nozzle-cylinder interaction. Through appropriate superposition of the above stress-intensity-magnification factors, stress-intensity factors for hypothetical corner cracks at a nozzle-cylinder intersection subjected to internal pressure and transient thermal-stress loadings can be obtained. A description of a computer code based on this procedure as well as its applications in analyzing two corner-crack probems at a nozzle-cylinder intersection are discussed in this paper. (Auth.)

  17. Risk factors for psychological stress among international business travellers.

    Science.gov (United States)

    Striker, J; Luippold, R S; Nagy, L; Liese, B; Bigelow, C; Mundt, K A

    1999-04-01

    This study investigated sources of self reported psychological stress among international business travellers at the World Bank, following up on a previous study showing that travellers submitted more insurance claims for psychological disorders. Hypotheses were that work, personal, family, and health concerns, as well as time zone travel, contribute to travel stress. A travel survey was developed from focus groups and consisted of questions about these potential sources of travel stress. Surveys were sent to a random sample of staff, stratified by number of travel missions, age range, and sex. Canonical correlation analyses estimated the association between key survey items on sources of stress and two measures of travel stress. 498 staff completed the survey. More than a third reported high to very high travel stress. Correlations between predictors and travel stress showed that social and emotional concerns (such as impact of travel on family and sense of isolation) contributed the most to such stress, followed by health concerns, and workload upon return from travel. Surprisingly, time zone travel did not contribute to the self reported stress of these travellers. There were few modifiers of stress, although respondents suggested that a day of rest after travel and reduced workloads would help. The current study confirms clinical impressions about several correlates of travel stress. Similar research with travellers in other organisations could help to determine whether the findings from this study are valid and what measures can be taken to reduce the psychological health risks to travellers.

  18. Risk factors for psychological stress among international business travellers

    Science.gov (United States)

    Striker, J.; Luippold, R. S.; Nagy, L.; Liese, B.; Bigelow, C.; Mundt, K. A.

    1999-01-01

    OBJECTIVES: This study investigated sources of self reported psychological stress among international business travellers at the World Bank, following up on a previous study showing that travellers submitted more insurance claims for psychological disorders. Hypotheses were that work, personal, family, and health concerns, as well as time zone travel, contribute to travel stress. METHODS: A travel survey was developed from focus groups and consisted of questions about these potential sources of travel stress. Surveys were sent to a random sample of staff, stratified by number of travel missions, age range, and sex. Canonical correlation analyses estimated the association between key survey items on sources of stress and two measures of travel stress. RESULTS: 498 staff completed the survey. More than a third reported high to very high travel stress. Correlations between predictors and travel stress showed that social and emotional concerns (such as impact of travel on family and sense of isolation) contributed the most to such stress, followed by health concerns, and workload upon return from travel. Surprisingly, time zone travel did not contribute to the self reported stress of these travellers. There were few modifiers of stress, although respondents suggested that a day of rest after travel and reduced workloads would help. CONCLUSIONS: The current study confirms clinical impressions about several correlates of travel stress. Similar research with travellers in other organisations could help to determine whether the findings from this study are valid and what measures can be taken to reduce the psychological health risks to travellers.   PMID:10450241

  19. Weight functions for the determination of stress intensity factor and T-stress for edge-cracked plates with built-in ends

    International Nuclear Information System (INIS)

    Li, J.; Wang, X.; Tan, C.L.

    2004-01-01

    This paper presents the weight functions for the determination of the stress intensity factor and T-stress solutions for edge-cracked plates with built-in ends under complex stress distributions. First, a compliance analysis approach is used to calculate stress intensity factor and T-stress for edge cracks in finite width plates with built-in ends with uniform or linear stress distributions acting on the crack face. The results serve as the reference solutions for the next step in which the approaches of deriving weight functions from reference stress intensity factor and T-stress solutions developed for stress boundary conditions are extended to obtain the corresponding weight functions for edge-cracked plates with built-in ends. Finite element analysis is conducted to validate the derived solutions. The weight functions derived are suitable for obtaining stress intensity factors and T-stress solutions under any complex stress field

  20. Job Stress Risk Factors Among Power Generation and Machine Production Employees: A Case Study-2010

    OpenAIRE

    Z. Naghavi; M.R. Hajgholami; Y. Shokoohi; F. Zayeri

    2013-01-01

    Background and Objective: Job stress has been adverse effects on performance, quality of work, absents, unsafe behaviors and occupational accidents and also health problems. Risk factors of job stress can be different in various workplaces. Risk factors determination is the first step of job stress management. Identifying these risk factors among workers of Power production & Machine production industries was the aim of this study. Methods: First parts of Osipow questionnaire was used for ...

  1. Psychological stress-relieving effects of chewing - Relationship between masticatory function-related factors and stress-relieving effects.

    Science.gov (United States)

    Tasaka, Akinori; Kikuchi, Manaki; Nakanishi, Kousuke; Ueda, Takayuki; Yamashita, Shuichiro; Sakurai, Kaoru

    2018-01-01

    The objective of the present study was to investigate the relationship between masticatory function-related factors (masticatory performance, occlusal contact area, maximum bite force, number of chewing strokes, and muscle activity) and the stress-relieving effects of chewing. A total of 28 healthy male subjects were instructed to rest or chew for 10min after 30min of stress loading with arithmetic calculations. Their stress state was assessed by measuring salivary cortisol levels. Saliva was collected at three time points: before stress loading, immediately after stress loading, and 10min after stress loading. Compared to resting, chewing produced a significantly greater reduction in the rate of change in salivary cortisol levels 10min after stress loading. A negative correlation was observed between the rate of decrease in salivary cortisol levels and the number of chewing strokes. No significant correlation was observed between the rate of decrease in salivary cortisol levels and other measurement items. In healthy dentulous people, the number of chewing strokes has been shown to be a masticatory function-related factor that affects stress relief from chewing, suggesting the possibility that more appropriate chewing would produce a greater effect psychological stress relief. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  2. The Ca2+ induced two-component system, CvsSR regulates the Type III secretion system and the extracytoplasmic function sigma-factor AlgU in Pseudomonas syringae pv. tomato DC3000.

    Science.gov (United States)

    Fishman, Maxwell R; Zhang, Johnson; Bronstein, Philip A; Stodghill, Paul; Filiatrault, Melanie J

    2017-12-20

    Two-component systems (TCSs) of bacteria regulate many different aspects of the bacterial life cycle including pathogenesis. Most TCSs remain uncharacterized with no information about the signal(s) or regulatory targets and/or role in bacterial pathogenesis. Here, we characterized a TCS in the plant-pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 ( Pto ) composed of the histidine kinase, CvsS, and the response regulator, CvsR. CvsSR is necessary for virulence of Pto , since ΔcvsS and ΔcvsR strains produced fewer symptoms and demonstrated reduced growth on multiple hosts as compared to WT. We discovered that expression of cvsSR is induced by Ca 2+ concentrations found in leaf apoplastic fluid. Thus, Ca 2+ can be added to the list of signals that promote pathogenesis of Pto during host colonization. Through chromatin immunoprecipitation followed by next generation sequencing (ChIP-seq) and global transcriptome analysis (RNA-seq) we discerned the CvsR regulon. CvsR directly activated expression of the type III secretion system regulators, hrpR and hrpS , that regulates Pto virulence in a type III secretion system dependent manner. CvsR also indirectly repressed transcription of the extracytoplasmic sigma factor algU and production of alginate. Phenotypic analysis determined that CvsSR inversely regulated biofilm formation, swarming motility, and cellulose production in a Ca 2+ -dependent manner. Overall, our results show that CvsSR is a key regulatory hub critical for interaction with host plants. Importance Pathogenic bacteria must be able to react and respond to the surrounding environment, make use of available resources, and avert or counter host immune responses. Often, these abilities rely on two-component systems (TCSs) composed of interacting proteins that modulate gene expression. We identified a TCS in the plant-pathogenic bacterium Pseudomonas syringae that responds to the presence of calcium, which is an important signal during the plant

  3. Stress fracture risk factors in female football players and their clinical implications.

    Science.gov (United States)

    Warden, Stuart J; Creaby, Mark W; Bryant, Adam L; Crossley, Kay M

    2007-08-01

    A stress fracture represents the inability of the skeleton to withstand repetitive bouts of mechanical loading, which results in structural fatigue, and resultant signs and symptoms of localised pain and tenderness. Reports of stress fractures in female football players are not prevalent; however, they are probably under-reported and their importance lies in the morbidity that they cause in terms of time lost from participation. By considering risk factors for stress fractures in female football players it may be possible to reduce the impact of these troublesome injuries. Risk factors for stress fractures in female football players include intrinsic risk factors such as gender, endocrine, nutritional, physical fitness and neuromusculoskeletal factors, as well as extrinsic risk factors such as training programme, equipment and environmental factors. This paper discusses these risk factors and their implications in terms of developing prevention and management strategies for stress fractures in female football players.

  4. Comparative Analysis between Lean, Six Sigma and Lean Six Sigma Concepts

    Directory of Open Access Journals (Sweden)

    Alexandra Mirela Cristina MUNTEANU

    2017-06-01

    Full Text Available This paper analyzes the benefits of Lean Six Sigma in comparison with Lean and Six Sigma, traditional improvement methodologies. The introduction highlights the appearance of Lean Six Sigma, early 2000s, as well as the benefits brought by the integrated approach. The following parts of the study emphasize the main differences between methodologies and their commonalities based on their synergy. Finally the advantages of Lean Six Sigma versus Lean and Six Sigma are analyzed and systematized by author in order to reveal Lean Six Sigma’s benefits.

  5. De praktijk van Lean Six Sigma

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Koning, H.

    2008-01-01

    Zowel Lean als Six Sigma zijn benaderingen van kwaliteits- en efficiëntieverbetering die op dit moment sterk in de belangstelling staan van zowel de industrie als de dienstverlening. Lean Six Sigma integreert beide benaderingen. Ze wordt door sommigen gezien als panacee voor alle mogelijke

  6. Six Sigma: blauwdruk voor de kenniseconomie.

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Mast, J.

    2005-01-01

    Abstract Six Sigma is zo langzamerhand een niet weg te denken programma voor kwaliteits- en efficiencyverbeteringen. Het heeft met name voor enorme successen gezorgd in productiebedrijven. Six Sigma ligt ook onder vuur: het zou een trend zijn die voorbij gaat. De auteurs van dit artikel zijn het van

  7. Six Sigma als blauwdruk voor de kenniseconomie.

    NARCIS (Netherlands)

    de Mast, J.; Does, R.J.M.M.

    2005-01-01

    Abstract Six Sigma is zo langzamerhand een niet weg te denken programma voor kwaliteits- en efficiencyverbeteringen. Het heeft met name voor enorme successen gezorgd in productiebedrijven. Six Sigma ligt ook onder vuur: het zou een trend zijn die voorbij gaat. De auteurs van dit artikel zijn het van

  8. Some examples of instantons in sigma models

    International Nuclear Information System (INIS)

    Kogan, Ya.I.; Markushevich, D.G.; Morozov, A.Yu.; Ol'shanetskii, M.A.; Perelomov, A.M.; Roslyi, A.A.

    1989-01-01

    The paper considers (supersymmetric) sigma models in which the fields are defined on a Riemann surface of genus p and take values on a Kaehlerian manifold. Some mathematical methods for finding instantons and their zero modes in such sigma models are explained. Only holomorphic instantons are considered

  9. Sigma meson in heavy ion collision

    International Nuclear Information System (INIS)

    Cristian, Ivan; Fuchs, Christian

    2004-01-01

    We want to present a short theoretical prediction of the behaviour of the sigma meson in heavy ion collisions. It is considered that the sigma meson is a pion-pion correlation, resulting from the decay of the N*(1440) resonance. There will be presented some QMD simulations. (authors)

  10. Lean Six Sigma in a hospital

    NARCIS (Netherlands)

    van den Heuvel, J.; Does, R.J.M.M.; de Koning, H.

    2006-01-01

    Abstract Hospitals today face major challenges. Patients demand quality of care to be improved continuously. Health insurance companies demand the lowest possible prices. Lean Six Sigma is a program that can help healthcare providers to achieve these (seemingly) conflicting goals. Lean Six Sigma is

  11. Integrating the Many Facets of Six Sigma

    NARCIS (Netherlands)

    de Mast, J.

    2007-01-01

    We seek to provide a unified characterization of Six Sigma by studying the phenomenon from the perspectives of business economics, organizational theory, competitive strategy and industrial statistics, and we pinpoint its core methodological principles. We describe Six Sigma as a prescriptive

  12. Stress intensity factors and weight functions for cracks in front of notches

    International Nuclear Information System (INIS)

    Fett, T.

    1993-12-01

    The knowledge of stress intensity factors for cracks at notch roots is important for the fracture mechanical treatment of real components. Stress intensity factor solutions are available only for special notches and externally applied loads. For the treatment of more complex loadings as thermal stresses near the notch root the weight function is needed in addition. In the first part of this report weight functions for cracks in front of internal notches are derived from stress intensity factor solutions under external loading available in the literature. The second part deals with cracks in front of edge notches. Limit cases of stress intensity factors are derived which allow to estimate stress intensity factors for cracks in front of internal elliptical notches with arbitrary aspect ratio of the ellipse and for external notches. (orig.) [de

  13. Chronic Stress and Neuropathology: Neurochemical, Molecular, and Genetic Factors

    National Research Council Canada - National Science Library

    Koob, George F; Zorrilla, Eric P

    2005-01-01

    The work that constitutes this Final Addendum Report derived from the hypothesis that individual differences in stress reactivity derived from selective breeding generalize to a behavioral phenotype...

  14. Diagnosis of abiotic and biotic stress factors using the visible symptoms in foliage

    International Nuclear Information System (INIS)

    Vollenweider, P.; Guenthardt-Goerg, Madeleine S.

    2005-01-01

    Visible symptoms in the foliage of trees are recorded to monitor the effects of abiotic and biotic stress. Difficulties are reported in diagnosing the origin of stress. The present paper discusses several diagnostic criteria which are usable in different species for a better determination of the stress factor type. A new diagnosis scheme to differentiate between classes of abiotic and biotic stress factors is supplied. Abiotic stress generates gradients of symptoms. The symptom specificity is determined by the degree of interaction between the stress factor and plant defense system. Symptoms caused by abiotic stress and natural autumnal senescence can be morphologically different or undistinguishable according to the stress and plant species. With biotic stress, the class of parasitic is generally recognizable on the basis of the visible symptoms. Structurally and physiologically based explanations of the symptom morphology are still missing for many stress factors. - The morphology and distribution of visible stress symptoms in tree foliage provides diagnostic tools to identify plant defense responses and differentiate stress from natural senescence symptoms

  15. THE LEAN AND SIX SIGMA SINERGY

    Directory of Open Access Journals (Sweden)

    Mirko Sokovic

    2008-12-01

    Full Text Available Many organizations, dealing with continuous improvement methods, have realized that Lean and Six Sigma methodologies complement each other. Lean manufacturing focuses on the remova l of waste so that all processes in the total system add value from the customers' perspectives. The main emphasis of Six Sigma is the application of statistical tools in a disciplined manner, which requires data-driven decision-making. The integration of Lean and Six Sigma provides a synergetic effect, a rapid process improvement strategy for attaining organizational goals. When separated, Lean manufacturing cannot bring a process under statistical control, and Six Sigma cannot dramatically improve cycle time or reduce invested capital. Together, synergistic qualities are created to maximize the potential for a process improvement. The paper deals with Lean and Six Sigma principles and approaches used in modern manufacturing for process improvements, and bring forward benefits that are gained when these two methodologies are integrated.

  16. Predictive factors for acute stress disorder and posttraumatic stress disorder after motor vehicle accidents.

    Science.gov (United States)

    Yaşan, Aziz; Guzel, Aslan; Tamam, Yusuf; Ozkan, Mustafa

    2009-01-01

    Since traffic accidents are more common in developing countries than in developed countries, we aimed to investigate the association of several factors with the development and persistence of posttraumatic stress disorder (PTSD) after traffic accidents. In the study,95 participants with injuries from traffic accidents were evaluated at 4 different times: in the beginning, and after 3, 6 and 12 months. During the first evaluation, 41.1% (39) of our participants had acute stress disorder (ASD). It was found that lower perceived social support (OR = 0.0908, 95% CI = 0.834-0.989, p = 0.027) and higher peritraumatic dissociative experience scores (OR = 1.332, 95% CI = 1.170-1.516, p accident, we found PTSD affected 29.8, 23.1 and 17.9% of the participants, respectively. Although limitations at work and in social life after a traffic accident were not related to PTSD at 3 months (OR = 122.43, 95% CI = 0.000, p = 0.999) or at 6 months (OR = 63.438, 95% CI = 0.529-76.059, p = 0.089), limitations at work and in social life were predictors of PTSD at 12 months (OR = 155.514, 95% CI = 2.321-104.22, p = 0.019). The persistence of PTSD at the 12-month evaluation is related to ASD, limitations in work and social life, and lower social support scores. In developing countries like Turkey, long-term PTSD is commonly seen after traffic accidents. 2009 S. Karger AG, Basel.

  17. TA-55 and Sigma Overview

    Energy Technology Data Exchange (ETDEWEB)

    Spearing, Dane Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Safeguards Science and Technology Group (NEN-1)

    2016-11-29

    These are slides from a facility overview presentation for visiting agencies to Los Alamos National Laboratory (LANL). The TA-55 Plutonium Facility (PF-4) is discussed in detail. PF-4 is a unique resource for US plutonium programs. The basic design is flexible and has adapted to changing national needs. It is a robust facility with strong safety and security implementation. It supports a variety of national programs. It will continue for many years into the future. Sigma is then discussed in detail, which handles everything from hydrogen to uranium. It has been in long term service to the Nation (nearly 60 years). It has a flexible authorization basis to handle almost the entire periodic table. It has a wide breadth of prototyping and characterization capabilities. It has integrated program and line management.

  18. Nonabelian Gauged Linear Sigma Model

    Institute of Scientific and Technical Information of China (English)

    Yongbin RUAN

    2017-01-01

    The gauged linear sigma model (GLSM for short) is a 2d quantum field theory introduced by Witten twenty years ago.Since then,it has been investigated extensively in physics by Hori and others.Recently,an algebro-geometric theory (for both abelian and nonabelian GLSMs) was developed by the author and his collaborators so that he can start to rigorously compute its invariants and check against physical predications.The abelian GLSM was relatively better understood and is the focus of current mathematical investigation.In this article,the author would like to look over the horizon and consider the nonabelian GLSM.The nonabelian case possesses some new features unavailable to the abelian GLSM.To aid the future mathematical development,the author surveys some of the key problems inspired by physics in the nonabelian GLSM.

  19. Research Progress on Measurement Methods and Influence Factors of Thin-film Stress

    Directory of Open Access Journals (Sweden)

    MA Yibo

    2018-02-01

    Full Text Available With the size of thin-film electronic devices decreasing, the film stress became an important reason for the failure of thin film devices. Film stress not only affected the membrane structure, but also associated with film optics, electricity, mechanics and other properties, therefore film stress turned into one hot spot in the research field of thin-film materials. This paper reviewed the latest research progress of film stress, substrate curvature method, X-ray diffraction technique and Raman spectroscopy, several frequently used stress measuring techniques were compared and analyzed, and composition ratios of thin film, substrate types, magnetron sputtering process parameters (sputtering power, work pressure, substrate temperature and annealing etc. factors influencing thin film stress were summarized. It was found that substrate curvature method was suitable for measuring almost all kinds of thin film materials. X-ray diffraction and Raman spectroscopy were just fit for measuring materials with characteristic peaks. Nanoindentation method required extra stress-free samples as comparison experiments. During film fabrication and annealing process, film stress usually transited from compressive to tensile status, and several factors combined together could affect stress, so film stress could be reached the minimum value or even stress-free status through setting appropriate parameters. Finally, combined with film stress research status, accurate stress measurement methods for different materials as a thin-film stress research direction were introduced, and challenges in thin film detection range were pointed out.

  20. Stress and Single Professional Women: An Exploration of Causal Factors.

    Science.gov (United States)

    Fong, Margaret L.; Amatea, Ellen S.

    1992-01-01

    Explored stress, career satisfaction, career commitment, personal resources, and coping strategies for single, single-parent, married, and married-parent academic women (n=141). Results indicated single women had significantly higher levels of stress symptoms than married-parent women. Single women did not differ from multiple-role colleagues in…

  1. Women Superintendents Who Leave: Stress and Health Factors

    Science.gov (United States)

    Robinson, Kerry K.; Shakeshaft, Charol

    2015-01-01

    Previous research on stress in the workplace has demonstrated that it can have not only a current, but lasting effect on a worker's health. The superintendency is a stressful job due to all of the competing demands of running a school system, no matter the size. This exploratory study reexamined qualitative interview transcripts from Robinson's…

  2. Psychological stress as a risk factor for postoperative keloid recurrence.

    Science.gov (United States)

    Furtado, Fabianne; Hochman, Bernardo; Farber, Paulo Luiz; Muller, Marisa Campio; Hayashi, Lilian Fukusima; Ferreira, Lydia Masako

    2012-04-01

    To investigate psychological stress on the prognosis of the postoperative recurrence of keloids. Patients with keloids (n=25), candidates for surgical resection and postoperative radiotherapy, had their psychological stress evaluated on the day before the surgical procedure. The parameters evaluated were pain and itching (Visual Numerical Scale), quality of life (Questionnaire QualiFibro/Cirurgia Plástica-UNIFESP), perceived stress (Perceived Stress Scale), depression and anxiety (Hospital Depression and Anxiety Scale), salivary cortisol and minimum and maximum galvanic skin responses (GSR) at rest and under stress (i.e., while the questionnaires were being filled out). Patients were evaluated during the 3rd, 6th, 9th and 12th months of postoperative care. During each return visit, two experts classified the lesions as non-recurrent and recurrent. The recurrence group presented the greatest values in GSR during a stressful situation. The chance of recurrence increased by 34% at each increase of 1000 arbitrary units in maximum GSR during stress. Psychological stress influenced the recurrence of keloids. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. [Postpartum stress urinary incontinence and associated obstetric factors].

    Science.gov (United States)

    Wang, Xiao-rong; Shi, Jun-xia; Zhai, Gui-rong; Zhang, Wei-yuan

    2010-02-01

    To evaluate the effect of cesarean section (CS) and vaginal delivery (VD) on postpartum stress urinary incontinence (SUI) and pelvic floor muscles strength and to find out the correlated obstetric factors and prevention for postpartum SUI. Totally, 788 women, who visited the antenatal clinics, delivered and had the follow-up at 6-8 weeks after delivery in Beijing Obstetrics and Gynecology Hospital in the year of 2008, were enrolled in this study and were divided into 3 groups: CS group (n = 212); normal vaginal delivery (NVD) group (n = 534) and forceps delivery (FD) group (n = 42). Women in the NVD and FD group were merged into one VD group and then divided into SUI and non-SUI group. Information of delivery mode and the correlated obstetric factors were obtained through questionnaires and medical records. Femiscan pelvic floor muscle examine system was applied to measure the pelvic floor muscle strength to understand the relationship between postpartum SUI and pelvic floor muscle strength. (1) Incidence of SUI: the overall proportion of women who complained of urinary incontinence (UI) during pregnancy was 15.4% (121/788), and it was 15.9% (85/534), 11.9% (5/42) and 14.6% (31/212) in the NVD, FD and CS group, respectively (P > 0.05). The overall incidence of postpartum SUI was 17.1% (135/788), and it was 19.1% (102/534), 26.2% (11/42) and 10.4% (22/212) in the NVD, FD and CS group, respectively, with significant difference between the NVD and FD group, and between the CS and NVD group (all P factors of postpartum SUI: among the VD group, 113 women were in the postpartum SUI group and 463 in the non-SUI group. Univariate analysis and logistic multivariate analysis showed that delivery mode, neonatal birth weight and UI during pregnancy were risk factors of postpartum SUI. CS decreased and higher neonatal birth weight and UI during pregnancy increased the risk of postpartum SUI. In the VD group, neonatal birth weight, forceps delivery and UI during pregnancy

  4. FACTORS CAUSING OCCUPATIONAL STRESS AMONG SENIOR SECONDARY SCHOOL TEACHERS OF AMRITSAR DISTRICT

    Directory of Open Access Journals (Sweden)

    Mandeep Singh

    2009-12-01

    Full Text Available The study attempts to investigate the various factors causing occupational stress experienced by senior secondary school teachers. A sample of 100 teachers (50 science teachers and 50 physical education teachers was randomly selected. They were administered a comprehensive questionnaire which measures various factors of stress. Factor analyses were used to identify underlying factors causing stress. The analysis showed that non cooperation from the colleagues, hastiness to finish the work, unable to perform duty smoothly, unclear instructions and insufficient facilities, unclear expectations of higher authority and having more work load in less time were the significant factors causing occupational stress among the teachers. The monotonous nature of work, ignorance of higher authority and violation of administrative processes and policies were factors also contributing towards occupational stress among teachers

  5. Acidic pH shock induces the expressions of a wide range of stress-response genes

    Directory of Open Access Journals (Sweden)

    Hong Soon-Kwang

    2008-12-01

    Full Text Available Abstract Background Environmental signals usually enhance secondary metabolite production in Streptomycetes by initiating complex signal transduction system. It is known that different sigma factors respond to different types of stresses, respectively in Streptomyces strains, which have a number of unique signal transduction mechanisms depending on the types of environmental shock. In this study, we wanted to know how a pH shock would affect the expression of various sigma factors and shock-related proteins in S. coelicolor A3(2. Results According to the results of transcriptional and proteomic analyses, the major number of sigma factor genes were upregulated by an acidic pH shock. Well-studied sigma factor genes of sigH (heat shock, sigR (oxidative stress, sigB (osmotic shock, and hrdD that play a major role in the secondary metabolism, were all strongly upregulated by the pH shock. A number of heat shock proteins including the DnaK family and chaperones such as GroEL2 were also observed to be upregulated by the pH shock, while their repressor of hspR was strongly downregulated. Oxidative stress-related proteins such as thioredoxin, catalase, superoxide dismutase, peroxidase, and osmotic shock-related protein such as vesicle synthases were also upregulated in overall. Conclusion From these observations, an acidic pH shock was considered to be one of the strongest stresses to influence a wide range of sigma factors and shock-related proteins including general stress response proteins. The upregulation of the sigma factors and shock proteins already found to be related to actinorhodin biosynthesis was considered to have contributed to enhanced actinorhodin productivity by mediating the pH shock signal to regulators or biosynthesis genes for actinorhodin production.

  6. Regulation of hippocampal neurogenesis by systemic factors including stress, glucocorticoids, sleep, and inflammation

    NARCIS (Netherlands)

    Lucassen, P.J.; Oomen, C.; van Dam, A.-M.; Czéh, B.; Gage, F.H.; Kempermann, G.; Song, H.

    2008-01-01

    This review summarizes and discusses the regulation of adult neurogenesis and hippocampal cellular plasticity by systemic factors. We focus on the role of stress, glucocorticoids, and related factors such as sleep deprivation and inflammation.

  7. Effects of overload on the threshold stress intensity factor for SCC

    International Nuclear Information System (INIS)

    Takahashi, Koji; Ando, Kotoji; Miyazaki, Yuji; Hashikura, Yasuaki

    2009-01-01

    The effects of overload on the threshold stress intensity factor for stress corrosion crack (K ISCC ) of stainless steel were studied. Tensile overload was applied to a wedge opening loaded (WOL) specimen of SUS316. Then, SCC tests were carried out to determine the resultant K ISCC . As a result, the apparent value of K ISCC increases as increasing a stress intensity factor by tensile overload (K OV ). The effects of tensile overload on K ISCC and the threshold stress intensity factor range for fatigue (ΔK th ) were compared. It was found that the effects of tensile overload on K ISCC were larger than that on ΔK th . (author)

  8. Mother's postnatal stress: an investigation of links to various factors during pregnancy and post-partum.

    Science.gov (United States)

    Andersson, Ewa; Hildingsson, Ingegerd

    2016-12-01

    Higher levels of parental stress have long-term effects on children's health and could lead to dysfunction in the parent-child interaction. Different background factors can be predictors of high parental stress. The aim of this study was to examine parental stress among Swedish women and identify different factors linked to women's parental stress. About 702 women were recruited to a clinical study and followed up six months after birth. Data were collected by two questionnaires, and 279 women completed the Swedish Parental Stress Questionnaire (SPSQ). Less than very good mental health and depressive symptoms after birth were strongly associated with parental stress, and the strongest association was found between post-partum depressive symptoms and high levels of stress in the subscale Incompetence. Multiparity was associated with high stress in two subscales, and lower level of education was a protective factor for stress in nearly all subscales. Depressive symptoms and perceived poor mental health post-partum are the most important factors related to high parental stress. The results point to the importance of identifying and supporting mothers with depressive symptoms, since these women have both mental illness and increased stress. © 2015 Nordic College of Caring Science.

  9. Inhibition of Ribosome Recruitment Induces Stress Granule Formation Independently of Eukaryotic Initiation Factor 2α Phosphorylation

    OpenAIRE

    Mazroui, Rachid; Sukarieh, Rami; Bordeleau, Marie-Eve; Kaufman, Randal J.; Northcote, Peter; Tanaka, Junichi; Gallouzi, Imed; Pelletier, Jerry

    2006-01-01

    Cytoplasmic aggregates known as stress granules (SGs) arise as a consequence of cellular stress and contain stalled translation preinitiation complexes. These foci are thought to serve as sites of mRNA storage or triage during the cell stress response. SG formation has been shown to require induction of eukaryotic initiation factor (eIF)2α phosphorylation. Herein, we investigate the potential role of other initiation factors in this process and demonstrate that interfering with eIF4A activity...

  10. Life stress as potential risk factor for depression and burnout

    Directory of Open Access Journals (Sweden)

    T. Plieger

    2015-03-01

    Conclusion: By considering the influence of life stress it could be demonstrated that depression and burnout are not identical although they share substantial phenotypic variance (r = .46–.61. Most important, the trivariate associations are the same in a representative employee sample and in an inpatient clinical sample suggesting the same underlying mechanisms covering the whole range from normal behavior to psychopathology. However, only longitudinal data can show if burnout necessarily turns into depression with the consequence that the burnout – life stress association approaches the depression – life stress association over time.

  11. Factor Structure of the Acute Stress Disorder Scale in a Sample of Hurricane Katrina Evacuees

    Science.gov (United States)

    Edmondson, Donald; Mills, Mary Alice; Park, Crystal L.

    2010-01-01

    Acute stress disorder (ASD) is a poorly understood and controversial diagnosis (A. G. Harvey & R. A. Bryant, 2002). The present study used confirmatory factor analysis (CFA) to test the factor structure of the most widely used self-report measure of ASD, the Acute Stress Disorder Scale (R. A. Bryant, M. L. Moulds, & R. M. Guthrie, 2000),…

  12. Relationship between occupational stress and cardiovascular diseases risk factors in drivers.

    Science.gov (United States)

    Biglari, Hamed; Ebrahimi, Mohammad Hossein; Salehi, Maryam; Poursadeghiyan, Mohsen; Ahmadnezhad, Iman; Abbasi, Milad

    2016-11-18

    Of all work stressors, occupational stress is the leading cause of many disorders among workers. Drivers are classified as a high risk group for work related stress. This study set out to determine the relationship between risk factors of cardiovascular diseases and occupational stress among drivers. Two hundred and twenty two Ilam's intercity drivers were selected for the study. For measuring work stress, the Osipow work stress questionnaire was used. After a 10-h fasting period, systolic and diastolic blood pressure was recorded. Intravenous blood samples were taken to determine cholesterol, triglyceride and blood glucose levels. The independent samples t-test and Pearson's correlation test were used to assess the relationship between variables and occupational stress. Seventy-one percent of the intercity drivers suffered from average to acute stress, and 3.1% of them suffered from acute stress. There was no significant relationship between occupational stress and diastolic blood pressure (p = 0.254) among the drivers. Nevertheless, the Pearson's correlation test demonstrated a strong relationship between work stress and blood glucose (p stress were observed in the Ilam's intercity drivers. Occupational stress may have effect on blood glucose levels but the results did not suggest a considerable relationship between risk factors of cardiovascular diseases and occupational stress among intercity drivers. Int J Occup Med Environ Health 2016;29(6):895-901. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  13. Stress Sensors and Signal Transducers in Cyanobacteria

    Science.gov (United States)

    Los, Dmitry A.; Zorina, Anna; Sinetova, Maria; Kryazhov, Sergey; Mironov, Kirill; Zinchenko, Vladislav V.

    2010-01-01

    In living cells, the perception of environmental stress and the subsequent transduction of stress signals are primary events in the acclimation to changes in the environment. Some molecular sensors and transducers of environmental stress cannot be identified by traditional and conventional methods. Based on genomic information, a systematic approach has been applied to the solution of this problem in cyanobacteria, involving mutagenesis of potential sensors and signal transducers in combination with DNA microarray analyses for the genome-wide expression of genes. Forty-five genes for the histidine kinases (Hiks), 12 genes for serine-threonine protein kinases (Spks), 42 genes for response regulators (Rres), seven genes for RNA polymerase sigma factors, and nearly 70 genes for transcription factors have been successfully inactivated by targeted mutagenesis in the unicellular cyanobacterium Synechocystis sp. PCC 6803. Screening of mutant libraries by genome-wide DNA microarray analysis under various stress and non-stress conditions has allowed identification of proteins that perceive and transduce signals of environmental stress. Here we summarize recent progress in the identification of sensory and regulatory systems, including Hiks, Rres, Spks, sigma factors, transcription factors, and the role of genomic DNA supercoiling in the regulation of the responses of cyanobacterial cells to various types of stress. PMID:22294932

  14. Fibroblast growth factor 21 participates in adaptation to endoplasmic reticulum stress and attenuates obesity-induced hepatic metabolic stress.

    Science.gov (United States)

    Kim, Seong Hun; Kim, Kook Hwan; Kim, Hyoung-Kyu; Kim, Mi-Jeong; Back, Sung Hoon; Konishi, Morichika; Itoh, Nobuyuki; Lee, Myung-Shik

    2015-04-01

    Fibroblast growth factor 21 (FGF21) is an endocrine hormone that exhibits anti-diabetic and anti-obesity activity. FGF21 expression is increased in patients with and mouse models of obesity or nonalcoholic fatty liver disease (NAFLD). However, the functional role and molecular mechanism of FGF21 induction in obesity or NAFLD are not clear. As endoplasmic reticulum (ER) stress is triggered in obesity and NAFLD, we investigated whether ER stress affects FGF21 expression or whether FGF21 induction acts as a mechanism of the unfolded protein response (UPR) adaptation to ER stress induced by chemical stressors or obesity. Hepatocytes or mouse embryonic fibroblasts deficient in UPR signalling pathways and liver-specific eIF2α mutant mice were employed to investigate the in vitro and in vivo effects of ER stress on FGF21 expression, respectively. The in vivo importance of FGF21 induction by ER stress and obesity was determined using inducible Fgf21-transgenic mice and Fgf21-null mice with or without leptin deficiency. We found that ER stressors induced FGF21 expression, which was dependent on a PKR-like ER kinase-eukaryotic translation factor 2α-activating transcription factor 4 pathway both in vitro and in vivo. Fgf21-null mice exhibited increased expression of ER stress marker genes and augmented hepatic lipid accumulation after tunicamycin treatment. However, these changes were attenuated in inducible Fgf21-transgenic mice. We also observed that Fgf21-null mice with leptin deficiency displayed increased hepatic ER stress response and liver injury, accompanied by deteriorated metabolic variables. Our results suggest that FGF21 plays an important role in the adaptive response to ER stress- or obesity-induced hepatic metabolic stress.

  15. Interaction of sigma 70 with Escherichia coli RNA polymerase core enzyme studied by surface plasmon resonance.

    Science.gov (United States)

    Ferguson, A L; Hughes, A D; Tufail, U; Baumann, C G; Scott, D J; Hoggett, J G

    2000-09-22

    The interaction between the core form of bacterial RNA polymerases and sigma factors is essential for specific promoter recognition, and for coordinating the expression of different sets of genes in response to varying cellular needs. The interaction between Escherichia coli core RNA polymerase and sigma 70 has been investigated by surface plasmon resonance. The His-tagged form of sigma 70 factor was immobilised on a Ni2+-NTA chip for monitoring its interaction with core polymerase. The binding constant for the interaction was found to be 1.9x10(-7) M, and the dissociation rate constant for release of sigma from core, in the absence of DNA or transcription, was 4x10(-3) s(-1), corresponding to a half-life of about 200 s.

  16. Determinants of job stress in chemical process industry: A factor analysis approach.

    Science.gov (United States)

    Menon, Balagopal G; Praveensal, C J; Madhu, G

    2015-01-01

    Job stress is one of the active research domains in industrial safety research. The job stress can result in accidents and health related issues in workers in chemical process industries. Hence it is important to measure the level of job stress in workers so as to mitigate the same to avoid the worker's safety related problems in the industries. The objective of this study is to determine the job stress factors in the chemical process industry in Kerala state, India. This study also aims to propose a comprehensive model and an instrument framework for measuring job stress levels in the chemical process industries in Kerala, India. The data is collected through a questionnaire survey conducted in chemical process industries in Kerala. The collected data out of 1197 surveys is subjected to principal component and confirmatory factor analysis to develop the job stress factor structure. The factor analysis revealed 8 factors that influence the job stress in process industries. It is also found that the job stress in employees is most influenced by role ambiguity and the least by work environment. The study has developed an instrument framework towards measuring job stress utilizing exploratory factor analysis and structural equation modeling.

  17. Lean Six Sigma implementation and organizational culture.

    Science.gov (United States)

    Knapp, Susan

    2015-01-01

    The purpose of this paper is to examine the relationship between four organizational cultural types defined by the Competing Values Framework and three Lean Six Sigma implementation components - management involvement, use of Lean Six Sigma methods and Lean Six Sigma infrastructure. The study involved surveying 446 human resource and quality managers from 223 hospitals located in Maine, New Hampshire, Vermont, Massachusetts and Rhode Island using the Organizational Culture Assessment Instrument. Findings - In total, 104 completed responses were received and analyzed using multivariate analysis of variance. Follow-up analysis of variances showed management support was significant, F(3, 100)=4.89, p cultures having significant interactions with management support. The relationship between organizational culture and Lean Six Sigma in hospitals provides information on how specific cultural characteristics impact the Lean Six Sigma initiative key components. This information assists hospital staff who are considering implementing quality initiatives by providing an understanding of what cultural values correspond to effective Lean Six Sigma implementation. Managers understanding the quality initiative cultural underpinnings, are attentive to the culture-shared values and norm's influence can utilize strategies to better implement Lean Six Sigma.

  18. Chronic Stress and Neuropathology: Neurochemical, Molecular, and Genetic Factors

    National Research Council Canada - National Science Library

    Koob, George F; Zorrilla, Eric P

    2005-01-01

    ... to selective breeding in the rat. Genetic differences in stress responsiveness in replicate line 1 were associated with differences in anxiety-like behavior, body weight gain and voluntary intake of sweet solutions and ethanol...

  19. Confirmatory factor analysis of posttraumatic stress symptoms in sexually harassed women.

    Science.gov (United States)

    Palmieri, Patrick A; Fitzgerald, Louise F

    2005-12-01

    Posttraumatic stress disorder (PTSD) factor analytic research to date has not provided a clear consensus on the structure of posttraumatic stress symptoms. Seven hypothesized factor structures were evaluated using confirmatory factor analysis of the Posttraumatic Stress Disorder Checklist, a paper-and-pencil measure of posttraumatic stress symptom severity, in a sample of 1,218 women who experienced a broad range of workplace sexual harassment. The model specifying correlated re-experiencing, effortful avoidance, emotional numbing, and hyperarousal factors provided the best fit to the data. Virtually no support was obtained for the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV; American Psychiatric Association, 1994) three-factor model of re-experiencing, avoidance, and hyperarousal factors. Different patterns of correlations with external variables were found for the avoidance and emotional numbing factors, providing further validation of the supported model.

  20. A crack opening stress equation for fatigue crack growth

    Science.gov (United States)

    Newman, J. C., Jr.

    1984-01-01

    A general crack opening stress equation is presented which may be used to correlate crack growth rate data for various materials and thicknesses, under constant amplitude loading, once the proper constraint factor has been determined. The constraint factor, alpha, is a constraint on tensile yielding; the material yields when the stress is equal to the product of alpha and sigma. Delta-K (LEFM) is plotted against rate for 2024-T3 aluminum alloy specimens 2.3 mm thick at various stress ratios. Delta-K sub eff was plotted against rate for the same data with alpha = 1.8; the rates correlate well within a factor of two.

  1. Determinants of Perceived Stress in Individuals with Obesity: Exploring the Relationship of Potentially Obesity-Related Factors and Perceived Stress.

    Science.gov (United States)

    Junne, Florian; Ziser, Katrin; Giel, Katrin Elisabeth; Schag, Kathrin; Skoda, Eva; Mack, Isabelle; Niess, Andreas; Zipfel, Stephan; Teufel, Martin

    2017-01-01

    Associations of specific types of stress with increased food intake and subsequent weight gain have been demonstrated in animal models as well as in experimental and epidemiological studies on humans. This study explores the research question of to what extent potentially obesity-related factors determine perceived stress in individuals with obesity. N = 547 individuals with obesity participated in a cross-sectional study assessing perceived stress as the outcome variable and potential determinants of stress related to obesity. Based on the available evidence, a five factorial model of 'obesity-related obesogenic stressors' was hypothesized, including the dimensions, 'drive for thinness', 'impulse regulation', 'ineffectiveness', 'social insecurity', and 'body dissatisfaction'. The model was tested using multiple linear regression analyses. The five factorial model of 'potentially obesity-related stressors' resulted in a total variance explanation of adjusted R² = 0.616 for males and adjusted R² = 0.595 for females for perceived stress. The relative variance contribution of the five included factors differed substantially for the two sexes. The findings of this cross-sectional study support the hypothesized, potentially obesity-related factors: 'drive for thinness', 'impulse regulation', 'ineffectiveness', 'social insecurity', and 'body dissatisfaction' as relevant determinants of perceived stress in individuals with obesity. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

  2. Assessment of oxidative stress parameters of brain-derived neurotrophic factor heterozygous mice in acute stress model

    Directory of Open Access Journals (Sweden)

    Gulay Hacioglu

    2016-04-01

    Full Text Available Objective(s: Exposing to stress may be associated with increased production of reactive oxygen species (ROS. Therefore, high level of oxidative stress may eventually give rise to accumulation of oxidative damage and development of numerous neurodegenerative diseases. It has been presented that brain-derived neurotrophic factor (BDNF supports neurons against various neurodegenerative conditions. Lately, there has been growing evidence that changes in the cerebral neurotrophic support and especially in the BDNF expression and its engagement with ROS might be important in various disorders and neurodegenerative diseases. Hence, we aimed to investigate protective effects of BDNF against stress-induced oxidative damage. Materials and Methods: Five- to six-month-old male wild-type and BDNF knock-down mice were used in this study. Activities of catalase (CAT and superoxide dismutase (SOD enzymes, and the amount of malondialdehyde (MDA were assessed in the cerebral homogenates of studied groups in response to acute restraint stress. Results: Exposing to acute physiological stress led to significant elevation in the markers of oxidative stress in the cerebral cortexes of experimental groups. Conclusion: As BDNF-deficient mice were observed to be more susceptible to stress-induced oxidative damage, it can be suggested that there is a direct interplay between oxidative stress indicators and BDNF levels in the brain.

  3. Recent advances in utilizing transcription factors to improve plant abiotic stress tolerance by transgenic technology

    Directory of Open Access Journals (Sweden)

    Hongyan eWang

    2016-02-01

    Full Text Available Agricultural production and quality are adversely affected by various abiotic stresses worldwide and this will be exacerbated by the deterioration of global climate. To feed a growing world population, it is very urgent to breed stress-tolerant crops with higher yields and improved qualities against multiple environmental stresses. Since conventional breeding approaches had marginal success due to the complexity of stress tolerance traits, the transgenic approach is now being popularly used to breed stress-tolerant crops. So identifying and characterizing the the critical genes involved in plant stress responses is an essential prerequisite for engineering stress-tolerant crops. Far beyond the manipulation of single functional gene, engineering certain regulatory genes has emerged as an effective strategy now for controlling the expression of many stress-responsive genes. Transcription factors (TFs are good candidates for genetic engineering to breed stress-tolerant crop because of their role as master regulators of many stress-responsive genes. Many TFs belonging to families AP2/EREBP, MYB, WRKY, NAC, bZIP have been found to be involved in various abiotic stresses and some TF genes have also been engineered to improve stress tolerance in model and crop plants. In this review, we take five large families of TFs as examples and review the recent progress of TFs involved in plant abiotic stress responses and their potential utilization to improve multiple stress tolerance of crops in the field conditions.

  4. SIGMA WEB INTERFACE FOR REACTOR DATA APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Pritychenko,B.; Sonzogni, A.A.

    2010-05-09

    We present Sigma Web interface which provides user-friendly access for online analysis and plotting of the evaluated and experimental nuclear reaction data stored in the ENDF-6 and EXFOR formats. The interface includes advanced browsing and search capabilities, interactive plots of cross sections, angular distributions and spectra, nubars, comparisons between evaluated and experimental data, computations for cross section data sets, pre-calculated integral quantities, neutron cross section uncertainties plots and visualization of covariance matrices. Sigma is publicly available at the National Nuclear Data Center website at http://www.nndc.bnl.gov/sigma.

  5. Sigma Web Interface For Reactor Data Applications

    International Nuclear Information System (INIS)

    Pritychenko, B.; Sonzogni, A.A.

    2010-01-01

    We present Sigma Web interface which provides user-friendly access for online analysis and plotting of the evaluated and experimental nuclear reaction data stored in the ENDF-6 and EXFOR formats. The interface includes advanced browsing and search capabilities, interactive plots of cross sections, angular distributions and spectra, nubars, comparisons between evaluated and experimental data, computations for cross section data sets, pre-calculated integral quantities, neutron cross section uncertainties plots and visualization of covariance matrices. Sigma is publicly available at the National Nuclear Data Center website at http://www.nndc.bnl.gov/sigma.

  6. Plant Abiotic Stress Proteomics: The Major Factors Determining Alterations in Cellular Proteome

    Science.gov (United States)

    Kosová, Klára; Vítámvás, Pavel; Urban, Milan O.; Prášil, Ilja T.; Renaut, Jenny

    2018-01-01

    HIGHLIGHTS: Major environmental and genetic factors determining stress-related protein abundance are discussed.Major aspects of protein biological function including protein isoforms and PTMs, cellular localization and protein interactions are discussed.Functional diversity of protein isoforms and PTMs is discussed. Abiotic stresses reveal profound impacts on plant proteomes including alterations in protein relative abundance, cellular localization, post-transcriptional and post-translational modifications (PTMs), protein interactions with other protein partners, and, finally, protein biological functions. The main aim of the present review is to discuss the major factors determining stress-related protein accumulation and their final biological functions. A dynamics of stress response including stress acclimation to altered ambient conditions and recovery after the stress treatment is discussed. The results of proteomic studies aimed at a comparison of stress response in plant genotypes differing in stress adaptability reveal constitutively enhanced levels of several stress-related proteins (protective proteins, chaperones, ROS scavenging- and detoxification-related enzymes) in the tolerant genotypes with respect to the susceptible ones. Tolerant genotypes can efficiently adjust energy metabolism to enhanced needs during stress acclimation. Stress tolerance vs. stress susceptibility are relative terms which can reflect different stress-coping strategies depending on the given stress treatment. The role of differential protein isoforms and PTMs with respect to their biological functions in different physiological constraints (cellular compartments and interacting partners) is discussed. The importance of protein functional studies following high-throughput proteome analyses is presented in a broader context of plant biology. In summary, the manuscript tries to provide an overview of the major factors which have to be considered when interpreting data from proteomic

  7. Risk factors in pregnancy for post-traumatic stress and depression after childbirth.

    Science.gov (United States)

    Söderquist, J; Wijma, B; Thorbert, G; Wijma, K

    2009-04-01

    The objective of this study was to find risk factors in pregnancy for post-traumatic stress and depression 1 month after childbirth. Furthermore, the relation between post-traumatic stress and depression was explored. A prospective longitudinal study. Pregnant women in Linköping and Kalmar, Sweden. A total of 1224 women were assessed in pregnancy, week 12-20 and 32, as well as 1 month postpartum. Post-traumatic stress and depression after delivery were assessed 1 month postpartum. Potential risk factors were assessed in early and late pregnancy. Variables measured during pregnancy were trait anxiety, depression, fear of childbirth, childbirth-related traumatic stress, stress coping capacity, social support, parity, educational level, age, gestation week, parity, educational level, civil status, previous psychological/psychiatric counselling, and previous experience of any traumatic events. Delivery mode was assessed from the medical records. Prevalence of post-traumatic stress (criteria A, B, C, D, E, and F according to DSM-IV) and depression (Beck's depression inventory). One month postpartum, 12 (1.3%) women had post-traumatic stress (met symptom criteria B, C, and D for post-traumatic stress disorder according to Diagnostic and statistical manual of mental disorders, 4th edition [DSM-IV]). The most important risk factors in pregnancy were depression in early pregnancy (OR=16.3), severe fear of childbirth (OR=6.2), and 'pre'-traumatic stress (in view of the forthcoming delivery) in late pregnancy (OR=12.5). The prevalence of depression was 5.6%. Post-traumatic stress and depression were positively related 1 month postpartum and were predicted by mainly the same factors. Risk factors for post-traumatic stress and depression after childbirth can be assessed in early pregnancy. Post-traumatic stress and depression also seem to share the same underlying vulnerability factors.

  8. Brain-derived neurotropic factor polymorphisms, traumatic stress, mild traumatic brain injury, and combat exposure contribute to postdeployment traumatic stress.

    Science.gov (United States)

    Dretsch, Michael N; Williams, Kathy; Emmerich, Tanja; Crynen, Gogce; Ait-Ghezala, Ghania; Chaytow, Helena; Mathura, Venkat; Crawford, Fiona C; Iverson, Grant L

    2016-01-01

    In addition to experiencing traumatic events while deployed in a combat environment, there are other factors that contribute to the development of posttraumatic stress disorder (PTSD) in military service members. This study explored the contribution of genetics, childhood environment, prior trauma, psychological, cognitive, and deployment factors to the development of traumatic stress following deployment. Both pre- and postdeployment data on 231 of 458 soldiers were analyzed. Postdeployment assessments occurred within 30 days from returning stateside and included a battery of psychological health, medical history, and demographic questionnaires; neurocognitive tests; and blood serum for the D2 dopamine receptor (DRD2), apolipoprotein E (APOE), and brain-derived neurotropic factor (BDNF) genes. Soldiers who screened positive for traumatic stress at postdeployment had significantly higher scores in depression (d = 1.91), anxiety (d = 1.61), poor sleep quality (d = 0.92), postconcussion symptoms (d = 2.21), alcohol use (d = 0.63), traumatic life events (d = 0.42), and combat exposure (d = 0.91). BDNF Val66 Met genotype was significantly associated with risk for sustaining a mild traumatic brain injury (mTBI) and screening positive for traumatic stress. Predeployment traumatic stress, greater combat exposure and sustaining an mTBI while deployed, and the BDNF Met/Met genotype accounted for 22% of the variance of postdeployment PTSD scores (R (2)  = 0.22, P PTSD scores. These findings suggest predeployment traumatic stress, genetic, and environmental factors have unique contributions to the development of combat-related traumatic stress in military service members.

  9. Multiple NUCLEAR FACTOR Y transcription factors respond to abiotic stress in Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Li Xu

    Full Text Available Members of the plant NUCLEAR FACTOR Y (NF-Y family are composed of the NF-YA, NF-YB, and NF-YC subunits. In Brassica napus (canola, each of these subunits forms a multimember subfamily. Plant NF-Ys were reported to be involved in several abiotic stresses. In this study, we demonstrated that multiple members of thirty three BnNF-Ys responded rapidly to salinity, drought, or ABA treatments. Transcripts of five BnNF-YAs, seven BnNF-YBs, and two BnNF-YCs were up-regulated by salinity stress, whereas the expression of thirteen BnNF-YAs, ten BnNF-YBs, and four BnNF-YCs were induced by drought stress. Under NaCl treatments, the expression of one BnNF-YA10 and four NF-YBs (BnNF-YB3, BnNF-YB7, BnNF-YB10, and BnNF-YB14 were greatly increased. Under PEG treatments, the expression levels of four NF-YAs (BnNF-YA9, BnNF-YA10, BnNF-YA11, and BnNF-YA12 and five NF-YBs (BnNF-YB1, BnNF-YB8, BnNF-YB10, BnNF-YB13, and BnNF-YB14 were greatly induced. The expression profiles of 20 of the 27 salinity- or drought-induced BnNF-Ys were also affected by ABA treatment. The expression levels of six NF-YAs (BnNF-YA1, BnNF-YA7, BnNF-YA8, BnNF-YA9, BnNF-YA10, and BnNF-YA12 and seven BnNF-YB members (BnNF-YB2, BnNF-YB3, BnNF-YB7, BnNF-YB10, BnNF-YB11, BnNF-YB13, and BnNF-YB14 and two NF-YC members (BnNF-YC2 and BnNF-YC3 were greatly up-regulated by ABA treatments. Only a few BnNF-Ys were inhibited by the above three treatments. Several NF-Y subfamily members exhibited collinear expression patterns. The promoters of all stress-responsive BnNF-Ys harbored at least two types of stress-related cis-elements, such as ABRE, DRE, MYB, or MYC. The cis-element organization of BnNF-Ys was similar to that of Arabidopsis thaliana, and the promoter regions exhibited higher levels of nucleotide sequence identity with Brassica rapa than with Brassica oleracea. This work represents an entry point for investigating the roles of canola NF-Y proteins during abiotic stress responses and provides

  10. Multiple NUCLEAR FACTOR Y transcription factors respond to abiotic stress in Brassica napus L.

    Science.gov (United States)

    Xu, Li; Lin, Zhongyuan; Tao, Qing; Liang, Mingxiang; Zhao, Gengmao; Yin, Xiangzhen; Fu, Ruixin

    2014-01-01

    Members of the plant NUCLEAR FACTOR Y (NF-Y) family are composed of the NF-YA, NF-YB, and NF-YC subunits. In Brassica napus (canola), each of these subunits forms a multimember subfamily. Plant NF-Ys were reported to be involved in several abiotic stresses. In this study, we demonstrated that multiple members of thirty three BnNF-Ys responded rapidly to salinity, drought, or ABA treatments. Transcripts of five BnNF-YAs, seven BnNF-YBs, and two BnNF-YCs were up-regulated by salinity stress, whereas the expression of thirteen BnNF-YAs, ten BnNF-YBs, and four BnNF-YCs were induced by drought stress. Under NaCl treatments, the expression of one BnNF-YA10 and four NF-YBs (BnNF-YB3, BnNF-YB7, BnNF-YB10, and BnNF-YB14) were greatly increased. Under PEG treatments, the expression levels of four NF-YAs (BnNF-YA9, BnNF-YA10, BnNF-YA11, and BnNF-YA12) and five NF-YBs (BnNF-YB1, BnNF-YB8, BnNF-YB10, BnNF-YB13, and BnNF-YB14) were greatly induced. The expression profiles of 20 of the 27 salinity- or drought-induced BnNF-Ys were also affected by ABA treatment. The expression levels of six NF-YAs (BnNF-YA1, BnNF-YA7, BnNF-YA8, BnNF-YA9, BnNF-YA10, and BnNF-YA12) and seven BnNF-YB members (BnNF-YB2, BnNF-YB3, BnNF-YB7, BnNF-YB10, BnNF-YB11, BnNF-YB13, and BnNF-YB14) and two NF-YC members (BnNF-YC2 and BnNF-YC3) were greatly up-regulated by ABA treatments. Only a few BnNF-Ys were inhibited by the above three treatments. Several NF-Y subfamily members exhibited collinear expression patterns. The promoters of all stress-responsive BnNF-Ys harbored at least two types of stress-related cis-elements, such as ABRE, DRE, MYB, or MYC. The cis-element organization of BnNF-Ys was similar to that of Arabidopsis thaliana, and the promoter regions exhibited higher levels of nucleotide sequence identity with Brassica rapa than with Brassica oleracea. This work represents an entry point for investigating the roles of canola NF-Y proteins during abiotic stress responses and provides insight into

  11. Transient Stress Intensity Factors of Functionally Graded Hollow Cylinders with Internal Circumferential Cracks

    Directory of Open Access Journals (Sweden)

    Iman Eshraghi

    Full Text Available Abstract In this paper, transient thermomechanical stress intensity factors for functionally graded cylinders with complete internal circumferential cracks are obtained using the weight function method. The finite difference method is used to calculate the time dependent temperature distribution and thermal stresses along the cylinder thickness. Furthermore, finite element analysis is performed to determine the weight function coefficients and to investigate the accuracy of the predicted stress intensity factors from the weight functions. Variation of the stress intensity factors with time and effects of the material gradation on the results are investigated, as well. It is shown that the proposed technique can be used to accurately predict transient thermomechanical stress intensity factors for functionally graded cylinders with arbitrary material gradation.

  12. Multi-Agent Modeling in Managing Six Sigma Projects

    Directory of Open Access Journals (Sweden)

    K. Y. Chau

    2009-10-01

    Full Text Available In this paper, a multi-agent model is proposed for considering the human resources factor in decision making in relation to the six sigma project. The proposed multi-agent system is expected to increase the acccuracy of project prioritization and to stabilize the human resources service level. A simulation of the proposed multiagent model is conducted. The results show that a multi-agent model which takes into consideration human resources when making decisions about project selection and project team formation is important in enabling efficient and effective project management. The multi-agent modeling approach provides an alternative approach for improving communication and the autonomy of six sigma projects in business organizations.

  13. Ward Identity and Scattering Amplitudes for Nonlinear Sigma Models

    Science.gov (United States)

    Low, Ian; Yin, Zhewei

    2018-02-01

    We present a Ward identity for nonlinear sigma models using generalized nonlinear shift symmetries, without introducing current algebra or coset space. The Ward identity constrains correlation functions of the sigma model such that the Adler's zero is guaranteed for S -matrix elements, and gives rise to a subleading single soft theorem that is valid at the quantum level and to all orders in the Goldstone decay constant. For tree amplitudes, the Ward identity leads to a novel Berends-Giele recursion relation as well as an explicit form of the subleading single soft factor. Furthermore, interactions of the cubic biadjoint scalar theory associated with the single soft limit, which was previously discovered using the Cachazo-He-Yuan representation of tree amplitudes, can be seen to emerge from matrix elements of conserved currents corresponding to the generalized shift symmetry.

  14. DEPLOYMENT OF SIX SIGMA METHODOLOGY IN PHACOEMULSIFICATION CATARACT SURGERY

    Directory of Open Access Journals (Sweden)

    Ibrahim SAHBAZ

    2014-04-01

    Full Text Available The purpose of this study is to show how a public eye care center in Turkey initiated Six Sigma principles to reduce the number of complications encountered during and after phacoemulsification cataract surgeries. To analyze the 3-year data, main tools of Six Sigma’s Define-Measure-Analyze-Improve-Control (DMAIC improvement cycle such as SIPOC table, Fishbone Diagram and, Failure, Mode and Effect Analysis were implemented. Experience of the ophthalmic surgeon, patient’s anatomy, cooperation of patient during the surgery, sterilization and hygiene, attention of assistant surgeon, calibration of equipment and quality/chemical composition of intraocular material were identified to be Critical-to-Quality (CTQ factors for a successful phacoemulsification cataract surgery. The most frequently occurring complication was found to be iris atrophy. The process sigma level for the process was found to be 3.958.

  15. DEVELOPMENT OF SIX SIGMA INFRASTRUCTURE FOR STRABISMUS SURGERIES

    Directory of Open Access Journals (Sweden)

    Mehmet Tolga Taner

    2014-01-01

    Full Text Available The purpose of this study is to show how a private eye care center in Turkey developed a Six Sigma infrastructure to investigate the root causes of complications occuring during strabismus surgeries. To analyze the collected data, main tools of Six Sigma’s Define-Measure-Analyze-Improve-Control (DMAIC improvement cycle such as SIPOC table, Fishbone Diagram and, Failure, Mode and Effect Analysis were implemented. Patient’s eye anatomy, experience of the anesthesiologist, experience/attention of the strabismus surgeon was identified to be Critical-to-Quality (CTQ factors for a successful strabismus surgery. The most frequent complications of strabismus surgeries were found to be X, Y and Z. The process sigma level was found to be 3.2025.

  16. Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress.

    Science.gov (United States)

    Briones-Buixassa, Laia; Milà, Raimon; Mª Aragonès, Josep; Bufill, Enric; Olaya, Beatriz; Arrufat, Francesc Xavier

    2015-07-01

    Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science), Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms "stress*" AND "multiple sclerosis." Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9) were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14) were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

  17. Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress

    Directory of Open Access Journals (Sweden)

    Laia Briones-Buixassa

    2015-11-01

    Full Text Available Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science, Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms “stress*” AND “multiple sclerosis.” Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9 were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14 were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

  18. Evidence for the decay sigma+ --> pmu+ mu-.

    Science.gov (United States)

    Park, H K; Burnstein, R A; Chakravorty, A; Chen, Y C; Choong, W S; Clark, K; Dukes, E C; Durandet, C; Felix, J; Fu, Y; Gidal, G; Gustafson, H R; Holmstrom, T; Huang, M; James, C; Jenkins, C M; Jones, T; Kaplan, D M; Lederman, L M; Leros, N; Longo, M J; Lopez, F; Lu, L C; Luebke, W; Luk, K B; Nelson, K S; Perroud, J-P; Rajaram, D; Rubin, H A; Volk, J; White, C G; White, S L; Zyla, P

    2005-01-21

    We report the first evidence for the decay Sigma(+)-->pmu(+)mu(-) from data taken by the HyperCP (E871) experiment at Fermilab. Based on three observed events, the branching ratio is B(Sigma(+)-->pmu(+)mu(-))=[8.6(+6.6)(-5.4)(stat)+/-5.5(syst)]x10(-8). The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, Sigma(+)-->pP(0),P0-->mu(+)mu(-) with a P0 mass of 214.3+/-0.5 MeV/c(2) and branching ratio B(Sigma(+)-->pP(0),P0-->mu(+)mu(-))=[3.1(+2.4)(-1.9)(stat)+/-1.5(syst)]x10(-8).

  19. Lean six sigma application to transportation logistics

    Directory of Open Access Journals (Sweden)

    Simone Tavares Fernandes

    2012-06-01

    Full Text Available This work presents the application of Lean Six Sigma in a case study of a metallurgic industry. The Six Sigma and the Lean are two processes used by enterprises in Brazil and worldwide. Currently the integration of these processes is a challenge for these companies, which search a way more efficient to reduce their wastes and to adapt to the needs of their markets. The paper had as purpose to demonstrate the applicability of the Lean Six Sigma in a real logistical problem related to the transportation of goods among units of a metallurgic industry. The stages used for the solution of the problem follow the DMAIC cycle – Define, Measure, Analyze, Improve and Control. The paper presents in details the integrated approach of the improvement processes Lean and Six Sigma, their tools set, as well the excellent results obtained in the case study.

  20. Doubly graded sigma model with torsion

    International Nuclear Information System (INIS)

    Kowalski-Glikman, J.

    1986-08-01

    Using the Hull-Witten construction we show how to introduce torsion to the doubly graded sigma model. This construction enables us to find a link between this model and the ten-dimensional supergravity theory in superspace. (Auth.)

  1. Some examples of instantons in sigma models

    International Nuclear Information System (INIS)

    Kogan, Ya.; Markushevich, D.; Morozov, A.; Ol'shanetskya, M.; Perelomov, A.; Roslij, A.

    1988-01-01

    Instantons on some manifolds of type K3 are described. Zero modes in two-dimensional sigma models on such manifolds are counted. The necessary facts on K3 manifolds are exposed in monographs. Instanton configurations are described

  2. The GATA transcription factor egl-27 delays aging by promoting stress resistance in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Xiao Xu

    Full Text Available Stress is a fundamental aspect of aging, as accumulated damage from a lifetime of stress can limit lifespan and protective responses to stress can extend lifespan. In this study, we identify a conserved Caenorhabditis elegans GATA transcription factor, egl-27, that is involved in several stress responses and aging. We found that overexpression of egl-27 extends the lifespan of wild-type animals. Furthermore, egl-27 is required for the pro-longevity effects from impaired insulin/IGF-1 like signaling (IIS, as reduced egl-27 activity fully suppresses the longevity of worms that are mutant for the IIS receptor, daf-2. egl-27 expression is inhibited by daf-2 and activated by pro-longevity factors daf-16/FOXO and elt-3/GATA, suggesting that egl-27 acts at the intersection of IIS and GATA pathways to extend lifespan. Consistent with its role in IIS signaling, we found that egl-27 is involved in stress response pathways. egl-27 expression is induced in the presence of multiple stresses, its targets are significantly enriched for many types of stress genes, and altering levels of egl-27 itself affects survival to heat and oxidative stress. Finally, we found that egl-27 expression increases between young and old animals, suggesting that increased levels of egl-27 in aged animals may act to promote stress resistance. These results identify egl-27 as a novel factor that links stress and aging pathways.

  3. Effect of abiotic and biotic stress factors analysis using machine learning methods in zebrafish.

    Science.gov (United States)

    Gutha, Rajasekar; Yarrappagaari, Suresh; Thopireddy, Lavanya; Reddy, Kesireddy Sathyavelu; Saddala, Rajeswara Reddy

    2018-03-01

    In order to understand the mechanisms underlying stress responses, meta-analysis of transcriptome is made to identify differentially expressed genes (DEGs) and their biological, molecular and cellular mechanisms in response to stressors. The present study is aimed at identifying the effect of abiotic and biotic stress factors, and it is found that several stress responsive genes are common for both abiotic and biotic stress factors in zebrafish. The meta-analysis of micro-array studies revealed that almost 4.7% i.e., 108 common DEGs are differentially regulated between abiotic and biotic stresses. This shows that there is a global coordination and fine-tuning of gene regulation in response to these two types of challenges. We also performed dimension reduction methods, principal component analysis, and partial least squares discriminant analysis which are able to segregate abiotic and biotic stresses into separate entities. The supervised machine learning model, recursive-support vector machine, could classify abiotic and biotic stresses with 100% accuracy using a subset of DEGs. Beside these methods, the random forests decision tree model classified five out of 8 stress conditions with high accuracy. Finally, Functional enrichment analysis revealed the different gene ontology terms, transcription factors and miRNAs factors in the regulation of stress responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Dynamic stress intensity factors for a longitudinal semi-elliptical ...

    African Journals Online (AJOL)

    elliptical crack in a thick-walled cylinder subjected to transient dynamic stresses. First, the problem of dynamic elasticity in a thick-walled cylinder is solved analytically using the finite Hankel transform. Transient pressure is assumed to act on ...

  5. Prevalence and associated factors of stress, anxiety and depression ...

    African Journals Online (AJOL)

    Wafaa Yousif Abdel Wahed

    2016-02-20

    Feb 20, 2016 ... sion Depression, Anxiety and Stress Scale-21 (DASS-21), along with a pretested Sociodemographic questionnaire. .... sons.26 Most of them live in rural communities and work in ..... ing period.39 Results of other studies in North America also suggest that .... NIMH. National Institute of Mental Health; 2008.

  6. Pion--nucleon sigma-commutator

    International Nuclear Information System (INIS)

    Banerjee, M.K.; Cammarata, J.B.

    1977-07-01

    The reasons for the large discrepancies in the magnitude of the πN sigma-commutator, sigma(πN), obtained by several authors are discussed using dynamic theory of the πN scattering amplitude. With sigma(πN) approximately 25 MeV this theory reproduces reasonably well both the experimental S-wave phase shifts at low energies and the amplitudes C approximately/sup(+)/(ν=0,t less than or equal to 0) determined by Langbein. In the method of Cheng and Dashen the value of sigma(πN) is obtained from these amplitudes by extrapolation to t = 2m 2 /sub π/. A study of the experimental D-wave ''scattering lengths'' implies that the coefficient of the term quadratic in t in the Hoehler expansion of C approximately/sup(+)/(0,t) is negative. Adding such a term to the results of the S-wave theory will tend to improve the agreement for C approximately/sup (+)/(0,t less than or equal to 0). These results suggest that the large ''world value'' sigma(πN) = 65 +- 5 MeV obtained using the Cheng-Dashen method is a consequence of errors in the extrapolation of amplitudes to the unphysical point ν = 0, t = 2m 2 /sub π/. Only the smaller value sigma(πN) approximately 25 MeV appears to be consistent with the experimental data and theoretical constraints

  7. Stress-related factors in the emergence of transient global amnesia with hippocampal lesion

    Directory of Open Access Journals (Sweden)

    Juliane eDöhring

    2014-08-01

    Full Text Available The transient global amnesia (TGA is a rare amnesic syndrome that is characterized by an acute onset episode of an anterograde and retrograde amnesia. Its origin is still debated, but there is evidence for psychological factors involved in TGA. In neuroimaging, selective lesions in the CA1 fields of the hippocampus can be detected, a region that is particularly involved in the processing of memory, stress and emotion. The aim of this study was to assess the role of psychological stress in TGA by studying the prevalence of stress related precipitating events and individual stress-related personality profiles as well as coping strategies in patients. The hypothesis of a functional differentiation of the hippocampus in mnemonic and stress-related compartments was also evaluated. From all 113 patients, 18 % (n= 24 patients experienced emotional and psychological stress episodes directly before the TGA. In a cohort of 21 acute patients, TGA patients tend to cope with stress less efficiently and less constructively than controls. Patients who experienced a stress related precipitant event exhibited a higher level of anxiety in comparison to non-stress patients and controls. However, there was no difference between the general experience of stress and the number of stress inducing life events. The majority of patients (73% did show typical MRI lesions in the CA1 region of the hippocampal cornu ammonis. There was no clear association between stressful events, distribution of hippocampal CA1 lesions and behavioral patterns during the TGA. Disadvantageous coping strategies and an elevated anxiety level may increase the susceptibility to psychological stress which may facilitate the pathophysiological cascade in TGA. The findings suggest a role of emotional stress factors in the manifestation of TGA in a subgroup of patients. Stress may be one trigger involved in the emergence of transient lesions in the hippocampal CA1 region, which are thought to be the

  8. Factors related to teamwork performance and stress of operating room nurses.

    Science.gov (United States)

    Sonoda, Yukio; Onozuka, Daisuke; Hagihara, Akihito

    2018-01-01

    To evaluate operating room nurses' perception of teamwork performance and their level of mental stress and to identify related factors. Little is known about the factors affecting teamwork and the mental stress of surgical nurses, although the performance of the surgical team is essential for patient safety. The questionnaire survey for operation room nurses consisted of simple questions about teamwork performance and mental stress. Multivariate analyses were used to identify factors causing a sense of teamwork performance or mental stress. A large number of surgical nurses had a sense of teamwork performance, but 30-40% of operation room nurses were mentally stressed during surgery. Neither the patient nor the operation factors were related to the sense of teamwork performance in both types of nurses. Among scrub nurses, endoscopic and abdominal surgery, body mass index, blood loss and the American Society of Anesthesiologists physical status class were related to their mental stress. Conversely, circulating nurses were stressed about teamwork performance. The factors related to teamwork performance and mental stress during surgery differed between scrub and circulating nurses. Increased support for operation room nurses is necessary. The increased support leads to safer surgical procedures and better patient outcomes. © 2017 John Wiley & Sons Ltd.

  9. The effect of Residual Stress on the Stress Intensity Factor of Nuclear Material

    International Nuclear Information System (INIS)

    Song, Taek Ho

    2008-01-01

    As NPP (Nuclear Power Plant) gets aged, the importance of the pressure boundary integrity increases very much to those who are trying to operate their plant beyond its design life. Not long ago, Boric acid crystal was found at the RPV outlet nozzle of V.C. Summer plant during the visual examination in 2000. After this finding, non-destructive examination was taken to find out what's taken place. As a result of this examination, circumferential and axial cracks were found. With Metallurgical structure examination, it was shown that crack had been developed at the mid-point between Inco-alloy buttering and weld metal. It was turned out that high welding residual stress was the main cause of the cracking. Because of the through wall crack, nozzle and welding parts were replaced. Many other nuclear power plants experienced similar pressure boundary stress corrosion cracks (SCCs). KEPRI (Korea Electric Power Research Institute) has carried out research projects for managing and preventing these kinds of cracks in nuclear power plants (NPPs). The titles of these research projects are 'Development of Stress Corrosion Cracking Management Technology and Aging Monitor for NPP Main Components' and 'Development of Analysis Technology for Crack Management of Dissimilar Metal Weld'. Through these projects, residual stress measurement techniques have been exercised at various points in mock-up test specimens to simulate nuclear power plant dissimilar base metal and weldment residual stress. X-ray test and hole drilling method have been reviewed to measure residual stresses of the dissimilar metal welds. This paper shows some point of view in residual stress measurement. Fracture mechanics analysis has been performed to explain the importance of residual stress measurement in association with nuclear power plant safety

  10. Stress intensity factor analyses of surface cracks in three-dimensional structures

    International Nuclear Information System (INIS)

    Miyazaki, Noriyuki; Shibata, Katsuyuki; Watanabe, Takayuki; Tagata, Kazunori.

    1983-11-01

    The stress intensity factor analyses of surface cracks in various three-dimensional structures were performed using the finite element computer program EPAS-J1. The results obtained by EPAS-J1 were compared with other finite element solutions or results obtained by the simplified estimation methods. Among the simplified estimation methods, the equations proposed by Newman and Raju give the distributions of the stress intensity factor along a crack front, which were compared with the result obtained by EPAS-J1. It was confirmed by comparing the results that EPAS-J1 gives reasonable stress intensity factors of surface cracks in three-dimensional structures. (author)

  11. Stress-intensity factor equations for cracks in three-dimensional finite bodies

    Science.gov (United States)

    Newman, J. C., Jr.; Raju, I. S.

    1981-01-01

    Empirical stress intensity factor equations are presented for embedded elliptical cracks, semi-elliptical surface cracks, quarter-elliptical corner cracks, semi-elliptical surface cracks at a hole, and quarter-elliptical corner cracks at a hole in finite plates. The plates were subjected to remote tensile loading. Equations give stress intensity factors as a function of parametric angle, crack depth, crack length, plate thickness, and where applicable, hole radius. The stress intensity factors used to develop the equations were obtained from three dimensional finite element analyses of these crack configurations.

  12. Numerical evaluation of stress intensity factor for vessel and pipe subjected to thermal shock

    International Nuclear Information System (INIS)

    Kim, Y.W.; Lee, H.Y.; Yoo, B.

    1994-01-01

    The thermal weight function method and the finite element method were employed in the numerical computation of the stress intensity factor for a cracked vessel and the cracked pipe subjected to thermal shock. A wall subjected to thermal shock was analyzed, and it has been shown that the effect of thermal shock on the stress intensity factor is dominant for the crack with small crack length to thickness ratio. Convection at the crack face had an influence on the stress intensity factor in the early stage of thermal shock. (Author)

  13. Calculation of mixed mode stress intensity factors using an alternating method

    International Nuclear Information System (INIS)

    Sakai, Takayuki

    1999-01-01

    In this study, mixed mode stress intensity factors (K I and K II ) of a square plate with a notch were calculated using a finite element alternating method. The obtained results were compared with the ones by a finite element method, and it was shown that the finite element alternating method can accurately estimate mixed mode stress intensity factors. Then, using this finite element alternating method, mixed mode stress intensity factors were calculated as changing the size and position of the notch, and its simplified equations were proposed. (author)

  14. [Factors Associated with Stress Check Attendance: Possible Effect of Timing of Annual Health Examination].

    Science.gov (United States)

    Ishimaru, Tomohiro; Hattori, Michihiro; Nagata, Masako; Kuwahara, Keisuke; Watanabe, Seiji; Mori, Koji

    2018-01-01

    The stress check program has been part of annual employees' health screening since 2015. Employees are recommended, but not obliged, to undergo the stress check offered. This study was designed to examine the factors associated with stress check attendance. A total of 31,156 Japanese employees who underwent an annual health examination and a stress check service at an Occupational Health Service Center in 2016 participated in this study. Data from the annual health examination and stress check service included stress check attendance, date of attendance (if implemented), gender, age, workplace industry, number of employees at the workplace, and tobacco and alcohol consumption. Data were analyzed using multiple logistic regression. The mean rate of stress check attendance was 90.8%. A higher rate of stress check attendance was associated with a lower duration from the annual health examination, age ≥30 years, construction and transport industry, and 50-999 employees at the workplace. A lower rate of stress check attendance was associated with medical and welfare industry and ≥1,000 employees at the workplace. These findings provide insights into developing strategies for improving the rate of stress check attendance. In particular, stress check attendance may improve if the stress check service and annual health examination are conducted simultaneously.

  15. Revisiting the Role of Plant Transcription Factors in the Battle against Abiotic Stress.

    Science.gov (United States)

    Khan, Sardar-Ali; Li, Meng-Zhan; Wang, Suo-Min; Yin, Hong-Ju

    2018-05-31

    Owing to diverse abiotic stresses and global climate deterioration, the agricultural production worldwide is suffering serious losses. Breeding stress-resilient crops with higher quality and yield against multiple environmental stresses via application of transgenic technologies is currently the most promising approach. Deciphering molecular principles and mining stress-associate genes that govern plant responses against abiotic stresses is one of the prerequisites to develop stress-resistant crop varieties. As molecular switches in controlling stress-responsive genes expression, transcription factors (TFs) play crucial roles in regulating various abiotic stress responses. Hence, functional analysis of TFs and their interaction partners during abiotic stresses is crucial to perceive their role in diverse signaling cascades that many researchers have continued to undertake. Here, we review current developments in understanding TFs, with particular emphasis on their functions in orchestrating plant abiotic stress responses. Further, we discuss novel molecular mechanisms of their action under abiotic stress conditions. This will provide valuable information for understanding regulatory mechanisms to engineer stress-tolerant crops.

  16. The Influence of Cardiac Risk Factor Burden on Cardiac Stress Test Outcomes.

    Science.gov (United States)

    Schrock, Jon W; Li, Morgan; Orazulike, Chidubem; Emerman, Charles L

    2011-06-01

    Chest pain is the most common admission diagnosis for observation unit patients. These patients often undergo cardiac stress testing to further risk stratify for coronary artery disease (CAD). The decision of whom to stress is currently based on clinical judgment. We sought to determine the influence of cardiac risk factor burden on cardiac stress test outcome for patients tested from an observation unit, inpatient or outpatient setting. We performed a retrospective observational cohort study for all patients undergoing stress testing in our institution from June 2006 through July 2007. Cardiac risk factors were collected at the time of stress testing. Risk factors were evaluated in a summative fashion using multivariate regression adjusting for age and known coronary artery disease. The model was tested for goodness of fit and collinearity and the c statistic was calculated using the receiver operating curve. A total of 4026 subjects were included for analysis of which 22% had known CAD. The rates of positive outcome were 89 (12.0%), 95 (12.6%), and 343 (16.9%) for the OU, outpatients, and hospitalized patients respectively. While the odds of a positive test outcome increased for additional cardiac risk factors, ROC curve analysis indicates that simply adding the number of risk factors does not add significant diagnostic value. Hospitalized patients were more likely to have a positive stress test, OR 1.41 (1.10 - 1.81). Our study does not support basing the decision to perform a stress test on the number of cardiac risk factors.

  17. Influence of stress factors and socio-demographic characteristics on the sleep quality of nursing students

    OpenAIRE

    Benavente, Sonia Betzabeth Ticona; Silva, Rodrigo Marques da; Higashi, Aline Baraldi; Guido, Laura de Azevedo; Costa, Ana Lucia Siqueira

    2014-01-01

    Objective:To analyze the influence of stress factors and socio-demographic characteristics on the sleep quality of nursing students. Method: An analytical cross-sectional and quantitative study, conducted with 151 nursing students in São Paulo between March and April of 2012. A form for socio-demographic characteristics, the Instrument to Evaluate Stress in Nursing Students and the Pittsburgh Sleep Index were applied. Results: High levels of stress was predominant for Time Management (27.8%) ...

  18. The Role of Trauma-Specific Irrational Beliefs and Sociodemographic Risk Factors in Posttraumatic Stress Responses

    OpenAIRE

    Hyland, Philip; Shevlin, Mark; Adamson, Gary; Boduszek, Daniel

    2013-01-01

    Posttraumatic stress responses have been linked to a range of social-cognitive and sociodemographic factors. Rational Emotive Behaviour Therapy suggests that responding to a traumatic life event with a set of irrational beliefs should play a crucial role in predicting the development of posttraumatic stress disorder (PTSD: Ellis, 2001). The current study assessed the role of trauma-specific irrational beliefs in the prediction of clinically relevant posttraumatic stress responses, while contr...

  19. Personal Risk and Resilience Factors in the Context of Daily Stress

    Science.gov (United States)

    Diehl, Manfred; Hay, Elizabeth L.; Chui, Helena

    2012-01-01

    This chapter focuses on the role that personal risk and resilience factors play as adults of all ages cope with the stressors encountered in everyday life. Theorists have suggested that researchers should focus on the effects of daily stress and coping rather than focusing exclusively on major life events and chronic stress and have proposed that understanding how adults cope with daily stress is a key aspect of understanding long-term well-being and adaptation in adulthood. After presenting a conceptual model outlining the major components of the daily stress process, the chapter reviews the existing empirical literature on personal risk and resilience factors in the context of daily stress. This research clearly suggests that there is no universal generalization that can be made regarding whether chronological age, in and of itself, confers greater vulnerability or resilience onto adults. Instead, we argue that researchers should ask when and under what conditions is age associated with greater vulnerability to daily stress and when and under what conditions is age associated with greater resilience to daily stress. Age differences in reactivity to daily stress are clearly embedded within a complex system of factors—structural, individual, and situational—that influence stress reactivity and stress recovery in several ways. This complexity should not be taken to mean that stress reactivity and recovery cannot be charted or understood. Researchers, however, will need to approach this complexity with a great deal of theoretical, methodological, and statistical rigor to move our understanding of the importance of age in shaping risk and resilience to daily stress forward. The final section of the chapter outlines several directions for future research in the area of aging and resilience. In particular, we argue that a focus on personal risk and resilience factors in the context of daily stress, in combination with the application of sophisticated statistical

  20. PWSCC Growth Assessment Model Considering Stress Triaxiality Factor for Primary Alloy 600 Components

    Directory of Open Access Journals (Sweden)

    Jong-Sung Kim

    2016-08-01

    Full Text Available We propose a primary water stress corrosion cracking (PWSCC initiation model of Alloy 600 that considers the stress triaxiality factor to apply to finite element analysis. We investigated the correlation between stress triaxiality effects and PWSCC growth behavior in cold-worked Alloy 600 stream generator tubes, and identified an additional stress triaxiality factor that can be added to Garud's PWSCC initiation model. By applying the proposed PWSCC initiation model considering the stress triaxiality factor, PWSCC growth simulations based on the macroscopic phenomenological damage mechanics approach were carried out on the PWSCC growth tests of various cold-worked Alloy 600 steam generator tubes and compact tension specimens. As a result, PWSCC growth behavior results from the finite element prediction are in good agreement with the experimental results.

  1. An empirical investigation on factors influencing on work stress: Evidence from banking industry

    Directory of Open Access Journals (Sweden)

    Alireza Davoudzadeh Moghaddam

    2015-08-01

    Full Text Available An individual with a career faced with various career challenges may experience work-related stress. Work related stress is a factor that threatens employees’ health. The most common negative consequences of stress are particularly the deterioration of performance and efficiency, decrease in productivity and quality of customer’s services, which results in health problems. Work-related stress is a global issue, and banks are no exception. This paper presents a survey to investigate the influencing factors on work stress in banking industry. The study designs a questionnaire and distributes it among 200 randomly selected bank department managers in city of Tehran, Iran. Using principle component analysis, the study has detected five factors including organizational characteristics, external environment, work content, personal characteristics and top management.

  2. Functional role of CCCTC binding factor (CTCF) in stress-induced apoptosis

    International Nuclear Information System (INIS)

    Li Tie; Lu Luo

    2007-01-01

    CTCF, a nuclear transcriptional factor, is a multifunctional protein and involves regulation of growth factor- and cytokine-induced cell proliferation/differentiation. In the present study, we investigated the role of CTCF in protecting stress-induced apoptosis in various human cell types. We found that UV irradiation and hyper-osmotic stress induced human corneal epithelial (HCE) and hematopoietic myeloid cell apoptosis detected by significantly increased caspase 3 activity and decreased cell viability. The stress-induced apoptotic response in these cells requires down-regulation of CTCF at both mRNA and protein levels, suggesting that CTCF may play an important role in downstream events of stress-induced signaling pathways. Inhibition of NFκB activity prevented stress-induced down-regulation of CTCF and increased cell viability against stress-induced apoptosis. The anti-apoptotic effect of CTCF was further studied by manipulating CTCF activities in HCE and hematopoietic cells. Transient transfection of cDNAs encoding full-length human CTCF markedly suppressed stress-induced apoptosis in these cells. In contrast, knocking down of CTCF mRNA using siRNA specific to CTCF significantly promoted stress-induced apoptosis. Thus, our results reveal that CTCF is a down stream target of stress-induced signaling cascades and it plays a significant anti-apoptotic role in regulation of stress-induced cellular responses in HCE and hematopoietic myeloid cells

  3. Prevalence of and Factors Associated with Work Stress in Academia in Tanzania

    Science.gov (United States)

    Mkumbo, Kitila

    2014-01-01

    Work stress has been identified as a common phenomenon in the teaching profession. However, little research has been done to examine the prevalence of and factors associated with work stress among employees in university context in Tanzania and sub-Saharan African countries in general. Using survey design within the quantitative approach, this…

  4. Smaller hippocampal volume as a vulnerability factor for the persistence of post-traumatic stress disorder

    NARCIS (Netherlands)

    van Rooij, S J H; Kennis, M; Sjouwerman, R; van den Heuvel, M P; Kahn, R S; Geuze, E

    2015-01-01

    BACKGROUND: Smaller hippocampal volume has often been observed in patients with post-traumatic stress disorder (PTSD). However, there is no consensus whether this is a result of stress/trauma exposure, or constitutes a vulnerability factor for the development of PTSD. Second, it is unclear whether

  5. Towards Resolving the Crab Sigma-Problem: A Linear Accelerator?

    Science.gov (United States)

    Contopoulos, Ioannis; Kazanas, Demosthenes; White, Nicholas E. (Technical Monitor)

    2002-01-01

    Using the exact solution of the axisymmetric pulsar magnetosphere derived in a previous publication and the conservation laws of the associated MHD flow, we show that the Lorentz factor of the outflowing plasma increases linearly with distance from the light cylinder. Therefore, the ratio of the Poynting to particle energy flux, generically referred to as sigma, decreases inversely proportional to distance, from a large value (typically approx. greater than 10(exp 4)) near the light cylinder to sigma approx. = 1 at a transition distance R(sub trans). Beyond this distance the inertial effects of the outflowing plasma become important and the magnetic field geometry must deviate from the almost monopolar form it attains between R(sub lc), and R(sub trans). We anticipate that this is achieved by collimation of the poloidal field lines toward the rotation axis, ensuring that the magnetic field pressure in the equatorial region will fall-off faster than 1/R(sup 2) (R being the cylindrical radius). This leads both to a value sigma = a(sub s) much less than 1 at the nebular reverse shock at distance R(sub s) (R(sub s) much greater than R(sub trans)) and to a component of the flow perpendicular to the equatorial component, as required by observation. The presence of the strong shock at R = R(sub s) allows for the efficient conversion of kinetic energy into radiation. We speculate that the Crab pulsar is unique in requiring sigma(sub s) approx. = 3 x 10(exp -3) because of its small translational velocity, which allowed for the shock distance R(sub s) to grow to values much greater than R(sub trans).

  6. Six sigma quality for fuel manufacturing

    International Nuclear Information System (INIS)

    Gabbani, M.D.; Onderwater, T.

    1997-01-01

    It is widely recognized that operational performance in product manufacturing is largely determined by understanding and maintaining process capability. By definition, Six Sigma is a statistical unit of measure reflecting process capability that yields less' than 6.8 defects per million product produced. Statistically, this translates into obtaining a long term manufacturing process capability of ± 4.5 standard deviations about the mean within specification limits. The heart of the Six Sigma program developed by the Six Sigma Academy is what we refer to as the Breakthrough Strategy. This rigorous analytical methodology is the driving force in obtaining world class performance of Six Sigma. The methodology applies statistical and practical tools in resolving a problem or improving a product or process. The application of Six Sigma focuses on attacking process input variables (independent) rather than the output variables. Focusing on these independent variables (temperature, power, force, etc.) and the variation in the end product they create, enables us to get to the root of the problem rather than react to the symptoms of the problem. In this manner we prevent defects from occurring rather than inspecting and monitoring the product. Why the need for such an ambitious program? It is estimated that the cost of failure (rework, scrap, warranties, etc.) can be as high as 15% of sales for companies typically operating at 3-4 sigma. In achieving Six Sigma, costs of failure are typically less than 5%. The thought of reducing business costs while achieving the recognition of being our customer's premier choice provides enormous incentive to reach such status. (author)

  7. Correlation holography: imaging of atoms when sigma/sub inelastic//sup >>sigma/elastic

    International Nuclear Information System (INIS)

    Csonka, P.L.

    1979-01-01

    Atomic-scale resolution of details is possible with this method, even if protons interact with the atoms overwhelmingly inelastically, i.e. when sigma/sub inelastic/ >>sigma/sub elastic/. Observation of small objects is compatible with quantum mechanics even if the disturbance of the object caused by the observation process is arbitrarily small

  8. Personality factors and posttraumatic stress: associations in civilians one year after air attacks.

    Science.gov (United States)

    Lecic-Tosevski, Dusica; Gavrilovic, Jelena; Knezevic, Goran; Priebe, Stefan

    2003-12-01

    There is an ongoing debate on which risk factors for developing posttraumatic stress symptoms are more important--personality traits reflecting vulnerability, previous stressful experiences or characteristics of the traumatic event. In this study, posttraumatic stress symptoms and their relationship with personality traits, previous stressful experiences and exposure to stressful events during air attacks in Yugoslavia were investigated. The Millon Clinical Multiaxial Inventory (MCMI; Millon, 1983), Impact of Events Scale (IES; Horowitz, Wilner, & Alvarez, 1979), Life Stressor Checklist Revised (LSCL-R; Wolfe & Kimerling, 1997), and List of Stressors were administered to a homogeneous group of medical students 1 year after the attacks. In multiple regression analyses, compulsive and passive-aggressive personality traits and a higher level of exposure to stressors during air attacks independently predicted the degree of intrusion symptoms. Avoidance symptoms were predicted by avoidant personality traits and a higher exposure to stressors both previously in life and during the attacks. In the next step, we tested in analyses of variance whether personality traits, previous stressful experiences, and stressful events during attacks as independent variables interact in predicting intrusion and avoidance symptoms. For this, students were clustered into three groups depending on their predominant personality traits. In addition to direct predictive effects, there were significant interaction effects in predicting both intrusion and avoidance. The findings suggest that each of the tested factors, i.e., personality traits, previous stressful experiences, and exposure to traumatic events may have an independent and direct influence on developing posttraumatic stress. However, the effect of these factors cannot just be added up. Rather, the factors interact in their impact on posttraumatic stress symptoms. Bigger samples and longitudinal designs will be required to

  9. Occupational stress and cardiovascular risk factors in high-ranking government officials and office workers.

    Science.gov (United States)

    Mirmohammadi, Seyyed Jalil; Taheri, Mahmoud; Mehrparvar, Amir Houshang; Heydari, Mohammad; Saadati Kanafi, Ali; Mostaghaci, Mehrdad

    2014-08-01

    Cardiovascular diseases are among the most important sources of mortality and morbidity, and have a high disease burden. There are some major well-known risk factors, which contribute to the development of these diseases. Occupational stress is caused due to imbalance between job demands and individual's ability, and it has been implicated as an etiology for cardiovascular diseases. This study was conducted to evaluate the cardiovascular risk factors and different dimensions of occupational stress in high-ranking government officials, comparing an age and sex-matched group of office workers with them. We invited 90 high-ranking officials who managed the main governmental offices in a city, and 90 age and sex-matched office workers. The subjects were required to fill the occupational role questionnaire (Osipow) which evaluated their personal and medical history as well as occupational stress. Then, we performed physical examination and laboratory tests to check for cardiovascular risk factors. Finally, the frequency of cardiovascular risk factors and occupational stress of two groups were compared. High-ranking officials in our study had less work experience in their current jobs and smoked fewer pack-years of cigarette, but they had higher waist and hip circumference, higher triglyceride level, more stress from role overload and responsibility, and higher total stress score. Our group of office workers had more occupational stress because of role ambiguity and insufficiency, but their overall job stress was less than officials. The officials have higher scores in some dimensions of occupational stress and higher overall stress score. Some cardiovascular risk factors were also more frequent in managers.

  10. FACTORS THAT AFFECT SOCIAL WORKERS’ JOB SATISFACTION, STRESS AND BURNOUT

    Directory of Open Access Journals (Sweden)

    Calitz, Taetske

    2014-11-01

    Full Text Available Social work was classified as a scare skill and the retention of social workers is an important aspect that needs urgent attention. The research goal of this study was to determine what degree of work engagement and job satisfaction South African social workers experience in their current positions and how this influences job turnover, burnout and the intention to leave the profession. The purpose was to determine the needs social workers experience that will affect turnover in the profession. The needs/problems social workers experienced were stress, burnout, lower job satisfaction and work engagement.

  11. Does Psychosocial Work Environment Factors Predict Stress and Mean Arterial Pressure in the Malaysian Industry Workers?

    OpenAIRE

    Javaid, Muhammad Umair; Isha, Ahmad Shahrul Nizam; Sabir, Asrar Ahmed; Ghazali, Zulkipli; Nübling, Matthias

    2018-01-01

    Psychosocial risks are considered as a burning issue in the Asia-Pacific region. The aim of this study was to investigate the impact of psychosocial work environment factors on health of petrochemical industry workers of Malaysia. In lieu to job demands-resources theory, significant positive associations were found between quantitative demands, work-family conflict, and job insecurity with stress, while a significant negative association of role clarity as a resource factor with stress was de...

  12. [The Effect of Social-Psychological Factors on the Development of Occupational Stress].

    Science.gov (United States)

    Kalinina, S A; Yushkova, O I

    2015-01-01

    The article presents data on social-psychological factors which cause the occupational stress. The results showed that there is a link between the level of work motivation and the physiological cost of work. We observed a number of peculiarities of occupational stress development caused by psychoemotional tension depending on the class of intensity of intellectual labor; we also studied biological age of the subjects. The speed of ageing of the employees who work under conditions of emotional stress (direct or indirect responsibility for the safety of other people) was found to increase. The study suggested promising directions of occupational stress prevention.

  13. Stress Causing Factors Among Teachers in Elementary Schools and Their Relationship with Demographic and Job Characteristics.

    Science.gov (United States)

    Agai-Demjaha, Teuta; Minov, Jordan; Stoleski, Sasho; Zafirova, Beti

    2015-09-15

    Once high levels of work-related stress among teachers were confirmed many studies concentrated on identifying and investigating key stress factors among school teachers. Unfortunately there are very few researches made on stress causing factors among teachers in Republic of Macedonia. To determine the most frequent stress causing factors among teachers in elementary schools and to investigate their relationship with demographic and job characteristics. We performed a descriptive-analytical model of a cross-sectional study which involved 300 teachers employed in nine elementary schools. Evaluation of examined subjects included completion of a specially designed questionnaire. Among six categories of factors that generate work related stress (job demands, control, relationships, role, changes and support) control and support had the highest mean scores. Within the control category the highest levels of perceived teacher's work-related stress were caused by the following factors - changes in terms and conditions without consultation and given responsibility without the authority to take decisions. 141 out of the interviewed teachers (47%) have mentioned changes in terms and conditions without consultation as very stressful, while another 50 (16.67%) have reported it as stressful. 123 out of interviewed teachers (41%) have stated given responsibility without the authority to take decisions as very stressful, with another 105 (35%) have reported it as stressful. In the category support the highest levels of perceived teacher's work-related stress were caused by stress factors - lack of funds/resources to do the job and limited or no access to training. Out of 300 interviewed teachers, 179 (59.67%) have reported lack of funds/resources to do the job as very stressful, while another 50 (16.67%) as stressful. There is no significant relationship between the stress factor limited or no access to training and demographic and job characteristics. Our findings confirm that

  14. THE DYNAMIC INTERCONNECTION BETWEEN MAN AND ENVIRONMENT, A FACTOR OF STRESS AND ECO STRESS

    Directory of Open Access Journals (Sweden)

    SIMIONESCU (BARBU IRINA

    2014-05-01

    Full Text Available The reason for writing this paper is the omnipresence but also the impact of stress in our times. In order to explain why stress has gained an important place in modern history, we need to understand the evolution of medical science and technology, which over the last decades, have taken important steps towards establishing the biological links between stress and human behaviour but also the political and cultural contexts that have endowed with meaning and authority the scientific knowledge. In the same time, we must concentrate on the interaction between the individual and his social and physical environment from a holistic perspective, surpassing the interdisciplinary limits. The term ‘stress’ is used as a metaphor for disasters at a macroeconomic level, when national economies are destabilized and recently it has been associated with the idea of environmental damage. All natural disasters are environmental events, and their impact on human beings (from a psychological, physical, economic and social point of view can be seen as a major eco-stress. It’s essential to understand man`s influence on the environment in order to review the attitude of communities that, under the pretext of modernity, continue to exert destructive actions

  15. Study on applicability of stress intensity factor solutions for flaw evaluation

    International Nuclear Information System (INIS)

    Miura, Naoki; Nagai, Masaki; Takahashi, Yukio

    2014-01-01

    Stress intensity factor is the quantity which characterizes the singularity of the stress field near a crack tip in the scheme of the linear elastic fracture mechanics, and is used for fatigue and/or SCC crack propagation evaluation. Stress intensity factor depends on the shape and the size of cracked structures, and is frequently prepared as the tabulated correction factors which are the functions of crack depth ratio, aspect ratio, etc. Some stress intensity factor solutions have been included in the JSME rules on fitness-for-service for nuclear power plants. Many of them have been significantly revised on the latest (2012) version of the rules, however, the validation of the revised solutions was not adequate so far. In this study, the implication of the revision was investigated together with its technical basis. A comprehensive comparison was made between available solutions including the 2008 and 2012 version of the rules. It was ascertained that the solutions in the 2012 version provided stress intensity factors consistent with the previous version and the referential stress intensity factors. (author)

  16. Interest and limits of the six sigma methodology in medical laboratory.

    Science.gov (United States)

    Scherrer, Florian; Bouilloux, Jean-Pierre; Calendini, Ors'Anton; Chamard, Didier; Cornu, François

    2017-02-01

    The mandatory accreditation of clinical laboratories in France provides an incentive to develop real tools to measure performance management methods and to optimize the management of internal quality controls. Six sigma methodology is an approach commonly applied to software quality management and discussed in numerous publications. This paper discusses the primary factors that influence the sigma index (the choice of the total allowable error, the approach used to address bias) and compares the performance of different analyzers on the basis of the sigma index. Six sigma strategy can be applied to the policy management of internal quality control in a laboratory and demonstrates through a comparison of four analyzers that there is no single superior analyzer in clinical chemistry. Similar sigma results are obtained using approaches toward bias based on the EQAS or the IQC. The main difficulty in using the six sigma methodology lies in the absence of official guidelines for the definition of the total error acceptable. Despite this drawback, our comparison study suggests that difficulties with defined analytes do not vary with the analyzer used.

  17. Integration of six sigma with lean production: an analysis through multiple cases

    Directory of Open Access Journals (Sweden)

    Thiago Henrique Pinheiro

    2013-08-01

    Full Text Available The intense competition between markets has taken companies, regardless of their size, to implement one or more quality improvement programs. One of the main purposes of these programs is the enhancement of company effectiveness and efficiency. There is today a growing interested in a proposal named Lean Six Sigma. Their objective is to apply six sigma concepts integrated with Lean Production. A model named Lean Six Sigma has raised interest, once its objective is to apply the concepts of the Six Sigma program integrating them with the principles of Lean Production. Six Sigma contributes with methods for problem identification, measurement and analysis, and the Lean Production offers techniques and procedures applied to reduce waste in the production. In this context, this paper aims at demonstrating the results of a field research, from which purpose was to identify relevant factors for Six Sigma implementation combined with Lean Production. To meet these objectives, three organizations from different industrial sectors were investigated. It was verified that in two of those companies, the programs were successfully implemented. Based on data analysis, it is possible to identify that one of the major difficulties encountered by the program leaders is related to the company’s human resources infra-structure. It is necessary to take into account that the conclusions are limited to a small sample of three units of analysis. However, this work offers the possibility of an analytical generalization.

  18. Identification of Risk Factors for Chronic Posttraumatic Stress Disorder (PTSD)

    National Research Council Canada - National Science Library

    Shea, M. T; Hebert, Norman J

    2007-01-01

    The primary research aims are to examine the early longitudinal course of PTSD symptoms and test hypotheses regarding risk factors for chronic PTSD in military personnel returning from Iraq or Afghanistan...

  19. The impact of environmental factors on nursing stress, job satisfaction, and turnover intention.

    Science.gov (United States)

    Applebaum, Diane; Fowler, Susan; Fiedler, Nancy; Osinubi, Omowunmi; Robson, Mark

    2010-01-01

    The purpose of this study was to investigate relationships between environmental factors of odor, noise, light, and color and perceived stress, job satisfaction, and turnover intention. The physical work environment may positively or negatively influence nurses' stress, and stress may negatively impact their job satisfaction and intention to change jobs. The research questions were answered using a descriptive, correlational design. The sample (n = 116) consisted of medical-surgical nurses working in acute-care settings. A 36-item questionnaire addressed odor, noise, light, color, perceived stress, job satisfaction, and turnover intention. Significant relationships were found between noise and perceived stress, perceived stress and job satisfaction, job satisfaction and turnover intention, and perceived stress and turnover intention. Nurses tend to overlook their physical environment and "do their job." Common environmental stressors in the work environment can be stressful to staff and influence job satisfaction and, ultimately, intention to change jobs. Mitigating or eliminating these environmental factors has the potential to improve staff satisfaction and retention. Stress influences nursing job satisfaction and, ultimately, intention to change jobs.

  20. Six Lessons We Learned Applying Six Sigma

    Science.gov (United States)

    Carroll, Napoleon; Casleton, Christa H.

    2005-01-01

    As Chief Financial Officer of Kennedy Space Center (KSC), I'm not only responsible for financial planning and accounting but also for building strong partnerships with the CFO customers, who include Space Shuttle and International Space Station operations as well all who manage the KSC Spaceport. My never ending goal is to design, manage and continuously improve our core business processes so that they deliver world class products and services to the CFO's customers. I became interested in Six Sigma as Christa Casleton (KSC's first Six Sigma Black belt) applied Six Sigma tools and methods to our Plan and Account for Travel Costs Process. Her analysis was fresh, innovative and thorough but, even more impressive, was her approach to ensure ongoing, continuous process improvement. Encouraged by the results, I launched two more process improvement initiatives aimed at applying Six Sigma principles to CFO processes that not only touch most of my employees but also have direct customer impact. As many of you know, Six Sigma is a measurement scale that compares the output of a process with customer requirements. That's straight forward, but demands that you not only understand your processes but also know your products and the critical customer requirements. The objective is to isolate and eliminate the causes of process variation so that the customer sees consistently high quality.

  1. An epidemiologic study of occupational stress factors in Mumbai police personnel.

    Science.gov (United States)

    Almale, Balaji D; Vankudre, Ashok J; Bansode-Gokhe, Seema S; Pawar, Vrushali K

    2014-01-01

    Occupational stress is common to each and every organization at various levels of hierarchy. The police organization is no exception to this. Rather policing is widely recognized as more stressful than any other occupation, nature of work, irregular duty hours, and many more factors, which can trigger stress. The present study was done to highlight some of these stressful factors in Mumbai police. Simple as well as systematic random sampling technique was adopted to get equal representation from each zone as well as region from Mumbai police. Occupational stress index (OSI) questionnaire was prepared, pilot tested, and validated for screening stress. We screened 276 policemen for occupational stress. Seventy-three percent of them were in the 30-50 years age group, and most of them (49%) studied up to H.S.C. Ninety-one percent were married and 56% had reported duty hours 12-16 h/day. Seventy-one percent were addicted to any of the substance. After screening we found 73% moderately stressed, whereas 18% highly stressed policemen. Sociodemographic factors which were age group (50-58 years), duration of service in years (>25 years), duration of duty hours (>16 h/day), addiction habits, and number of monthly holidays (no holiday). We found role ambiguity, under participation, role overload, strenuous working condition, and unprofitability as predominant scales in OSI. So prevention as well as management of stress in policemen is the necessity of the current situation. This stress can be managed at organizational level by adopting right techniques, whereas at individual level by habituating right behavior and attitude.

  2. Job stress and its related factors in accountant employees of Qazvin University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    S. Khoeniha

    2011-07-01

    Full Text Available Background and aims Job stress is defined as the harmful physical and emotional responses that occur when job requirements do not match the capabilities¸ resources ¸and needs. This factor can negatively influence worker’s mental and physical health and also decrease organizations productivity and success. Thus the aim of present study was to investigate the job stress and its related factors in accountant employees of Qazvin University of Medical Sciences in 1388.   Methods This study was a descriptive (cross-sectional research in which the sampling population included 80 accountant employees that were selected with census. The severity of job stress and its related factors were determined using a researcher-made questionnaire consisting of 36 items that validated by content validity. The reliability was also measured by test-retest (d=0/90 methods. Data was analyzed by descriptive analysis.     ResultsThe severity of job stress in most of accountant employees (%46/25 was in high level .There was a Significant relationship between severity of job stress and employees sex ¸ age and work record (p<0.001 . The higher job stress was experienced by women and employees with thelower age work record . Among different occupational stress variables, the most important factor that caused job stress was workload of the role (M=70/22. Conclusion With regard to the severity of job stress in accountant employees, it is necessary for organizational managers and policy makers to implement a protective strategy for prevention or alleviate longitudinal negative consequences of job stress in employees.

  3. In vitro activation of sigma-aminolevulinate dehydratase from far-red irradiated radish (Raphanus sativus L. ) seedlings by thioredoxin f

    Energy Technology Data Exchange (ETDEWEB)

    Balange, A.P. (Centre National de la Recherche Scientifique, Mont Saint Aignan (France). Laboratoire de Photobiologie); Lambert, C. (UER Scientifique de Luminy, Department de Biologie Moleculaire et Cellulaire, Marseille, France)

    1983-10-01

    sigma-Aminolevulinate dehydratase has been found to be activated in vitro by dithiotreitol and factors isolated from radish cotyledons grown under continuous far-red light. Cross experiments, between fructose 1-6 bisphosphatase system, and sigma-aminolevulinate dehydratase, show that these factors are functionally identical to thioredoxin f.

  4. Genetically engineered Rice with transcription factor DREB genes for abiotic stress tolerance(abstract)

    International Nuclear Information System (INIS)

    Datta, S.K.; Datta, K.

    2005-01-01

    Water stress (drought and Salinity) is the most severe limitation to rice productivity. Several breeding approaches (MAS, QTL) applied to suitable genotypes are in place at IRRI and elsewhere. Phenotyping of water stress tolerance is in progress with potential predictability. Dr. Shinozaki's group has cloned a number of transcription factor genes, which have been shown to work in Arabidopsis to achieve drought, cold, and salinity tolerant plants. None of these genes have as yet displayed their potential functioning in rice. Genetic engineering aims at cross talk between different stress signaling pathways leading to stress tolerance. Osmotic Adjustment (OA) is an effective component of abiotic stress (drought and salinity) tolerance in many plants including rice. When plant experiences water stress, OA contributes to turgor maintenance of both shoots and roots. Conventional breeding could not achieve the OA in rice excepting a few rice cultivars, which are partially adapted to water-stress conditions. Several stress-related genes have now been cloned and transferred in to enhance the osmolytes and some transgenic lines showed increased tolerance to osmotic stress. A few strategies could be effectively deployed for a better understanding of water-stress tolerance in rice and to develop transgenic rice, which can survive for a critical period of water-stress conditions: 1) Switching on of transcription factor regulating the expression of several genes related to abiotic stress, 2) Use of a suitable stress inducible promoter driving the target gene for an efficient and directed expression in plants, 3) Understanding of phenotyping and GxE in a given environment, 4) Selection of a few adaptive rice cultivars suitable in drought/salinity prone areas, 5) Microarray, proteomics, QTL and MAS may expedite the cloning and characterizing the stress induced genes, and 6) Finally, the efficient transformation system for generating a large number of transgenic rice of different

  5. Stress

    Science.gov (United States)

    ... can be life-saving. But chronic stress can cause both physical and mental harm. There are at least three different types of stress: Routine stress related to the pressures of work, family, and other daily responsibilities Stress brought about ...

  6. Factors related to stress and coping among Chinese nurses in Hong Kong.

    Science.gov (United States)

    Callaghan, P; Tak-Ying, S A; Wyatt, P A

    2000-06-01

    Few empirical studies have investigated the issues linked to Hong Kong nurses work-related health. The present study investigated factors related to stress and coping among Chinese nurses in Hong Kong. The researchers employed a cross-sectional survey and made within-group comparisons of nurses' stress and coping. Using stratified random sampling the researchers selected nurses from the mailing list of a local professional organization. One hundred and sixty-eight (33.6%) nurses responded. Nurses reported lower stress levels than other workers assessed with the same measure. Paediatric nurses reported the highest stress levels. Nurses at the lower grades reported higher stress levels than nurses at the higher grades. Single nurses had marginally higher stress scores than married nurses and females had slightly higher stress scores than males. However, none of these results were statistically significant. The respondents' major sources of stress were related to nursing issues like too much work, interpersonal relationships, and dealing with hospital administration. The respondents coped with their stresses by seeking support from friends and colleagues, using different cognitive strategies and through leisure activities. There was a statistically significant link between the respondents' stress and sickness levels. The results raise issues about the nature of nurses' working experiences.

  7. Serotonin regulates brain-derived neurotrophic factor expression in select brain regions during acute psychological stress

    Institute of Scientific and Technical Information of China (English)

    De-guo Jiang; Shi-li Jin; Gong-ying Li; Qing-qing Li; Zhi-ruo Li; Hong-xia Ma; Chuan-jun Zhuo; Rong-huan Jiang; Min-jie Ye

    2016-01-01

    Previous studies suggest that serotonin (5-HT) might interact with brain-derived neurotrophic factor (BDNF) during the stress response. However, the relationship between 5-HT and BDNF expression under purely psychological stress is unclear. In this study, one hour before psychological stress exposure, the 5-HT1A receptor agonist 8-OH-DPAT or antagonist MDL73005, or the 5-HT2A receptor agonist DOI or antagonist ketanserin were administered to rats exposed to psychological stress. Immunohistochemistry andin situ hybridization revealed that after psychological stress, with the exception of the ventral tegmental area, BDNF protein and mRNA expression levels were higher in the 5-HT1A and the 5-HT2A receptor agonist groups compared with the solvent control no-stress or psychological stress group in the CA1 and CA3 of the hippocampus, prefrontal cortex, central amygdaloid nucleus, dorsomedial hypothalamic nucleus, dentate gyrus, shell of the nucleus accumbens and the midbrain periaqueductal gray. There was no signiifcant difference between the two agonist groups. In contrast, after stress exposure, BDNF protein and mRNA expression levels were lower in the 5-HT1A and 5-HT2A receptor antagonist groups than in the solvent control non-stress group, with the exception of the ventral tegmental area. Our ifndings suggest that 5-HT regulates BDNF expression in a rat model of acute psychological stress.

  8. Experimental and numerical determination of critical stress intensity factor of aluminum curved thin sheets under tensile stress

    Energy Technology Data Exchange (ETDEWEB)

    Heidarvand, Majid; Soltani, Naser; Hajializadeh, Farshid [University of Tehran, Tehran (Iran, Islamic Republic of)

    2017-05-15

    We determined the fracture toughness of aluminum curved thin sheets using tensile stress tests and finite element method. We applied Linear elastic fracture mechanics (LEFM) and Feddersen procedure to evaluate stress intensity factor of the samples with central wire-cut cracks and fatigue cracks with different lengths to investigate the notch radius effect. Special fixture design was utilized to establish uniform stress distribution at the crack zone. Less than 9 % difference was found between the wire-cut and the fatigue cracked samples. Since generating central fatigue crack with different lengths required so much effort, wire-cut cracked samples were used to determine critical stress intensity factor. Finite element analysis was also performed on one-quarter of the specimen using both the singular Borsum elements and the regular isoparametric elements to further investigate fracture toughness of the samples. It was observed that the singular elements presented better results than the isoparametric ones. A slight difference was also found between the results obtained from finite element method using singular elements and the experimental results.

  9. Improved Formula for the Stress Intensity Factor of Semi-Elliptical Surface Cracks in Welded Joints under Bending Stress

    Science.gov (United States)

    Peng, Yang; Wu, Chao; Zheng, Yifu; Dong, Jun

    2017-01-01

    Welded joints are prone to fatigue cracking with the existence of welding defects and bending stress. Fracture mechanics is a useful approach in which the fatigue life of the welded joint can be predicted. The key challenge of such predictions using fracture mechanics is how to accurately calculate the stress intensity factor (SIF). An empirical formula for calculating the SIF of welded joints under bending stress was developed by Baik, Yamada and Ishikawa based on the hybrid method. However, when calculating the SIF of a semi-elliptical crack, this study found that the accuracy of the Baik-Yamada formula was poor when comparing the benchmark results, experimental data and numerical results. The reasons for the reduced accuracy of the Baik-Yamada formula were identified and discussed in this paper. Furthermore, a new correction factor was developed and added to the Baik-Yamada formula by using theoretical analysis and numerical regression. Finally, the predictions using the modified Baik-Yamada formula were compared with the benchmark results, experimental data and numerical results. It was found that the accuracy of the modified Baik-Yamada formula was greatly improved. Therefore, it is proposed that this modified formula is used to conveniently and accurately calculate the SIF of semi-elliptical cracks in welded joints under bending stress. PMID:28772527

  10. Determination of Stress Intensity Factor K1 from Two Fringe Orders by Fringe Multiplication and Sharpening

    International Nuclear Information System (INIS)

    Chen, Lei; Baek, Tae Hyun

    2007-01-01

    Stress intensity factor is one of the most important parameters in fracture mechanics. Both the stress field distribution and the crack propagation are closely related to these parameters. Due to the complexity of actual engineering problems, it is difficult to calculate the stress intensity factor by theoretical formulation, so photoelasticity method is a good choice. In this paper, modified two parameter method is employed to calculate stress intensity factor for opening mode by using data from more than one photoelastic fringe loop. For getting accurate experiment results, the initial fringes are doubled and sharpened by digital image programs from the fringe patterns obtained by a CCD camera. Photoelastic results are compared with those obtained by the use of empirical equation and FEM. Good agreement shows that the methods utilized in experiments are considerably reliable. The photoelastic experiment can be used for bench mark in theoretical study and other experiments

  11. Fluoro-Phenyl-Styrene-Sulfonamide, a Novel Inhibitor of σB Activity, Prevents the Activation of σB by Environmental and Energy Stresses in Bacillus subtilis

    Science.gov (United States)

    Ringus, Daina L.; Gaballa, Ahmed; Helmann, John D.; Wiedmann, Martin

    2013-01-01

    Sigma B (σB) is an alternative sigma factor that regulates the general stress response in Bacillus subtilis and in many other Gram-positive organisms. σB activity in B. subtilis is tightly regulated via at least three distinct pathways within a complex signal transduction cascade in response to a variety of stresses, including environmental stress, energy stress, and growth at high or low temperatures. We probed the ability of fluoro-phenyl-styrene-sulfonamide (FPSS), a small-molecule inhibitor of σB activity in Listeria monocytogenes, to inhibit σB activity in B. subtilis through perturbation of signal transduction cascades under various stress conditions. FPSS inhibited the activation of σB in response to multiple categories of stress known to induce σB activity in B. subtilis. Specifically, FPSS prevented the induction of σB activity in response to energy stress, including entry into stationary phase, phosphate limitation, and azide stress. FPSS also inhibited chill induction of σB activity in a ΔrsbV strain, suggesting that FPSS does not exclusively target the RsbU and RsbP phosphatases or the anti–anti-sigma factor RsbV, all of which contribute to posttranslational regulation of σB activity. Genetic and biochemical experiments, including artificial induction of σB, analysis of the phosphorylation state of the anti–anti-sigma factor RsbV, and in vitro transcription assays, indicate that while FPSS does not bind directly to σB to inhibit activity, it appears to prevent the release of B. subtilis σB from its anti-sigma factor RsbW. PMID:23524614

  12. Stress, coping and burnout among Intensive Care Unit nursing staff: associated factors.

    Science.gov (United States)

    Andolhe, Rafaela; Barbosa, Ricardo Luis; Oliveira, Elaine Machado de; Costa, Ana Lúcia Siqueira; Padilha, Katia Grillo

    2015-02-01

    Objective To investigate emotional stress, coping and burnout among nursing staff and their association with biosocial factors and characteristics of work in Intensive Care Units (ICU). Method This was a cross-sectional study, conducted in eight ICUs at a teaching hospital in the city of São Paulo, Brazil, in October 2012. Biosocial data and information about the professionals' work was gathered, and they were given the Scale of Occupational Stress, Scale of Occupational Coping, List of Signs and Symptoms of Stress and the Maslach Burnout Inventory. Results The study sample consisted of 287 subjects, predominately women, with partners and children. Most professionals presented moderate stress levels and control as a coping strategy (74.47% and 79.93%, respectively), and burnout was present among 12.54%. Factors associated with stress were related to working conditions. The most prevalent protective factors were having a partner, working in the clinical ICU and liking work, while adequate amount of sleep was a protective factor for burnout. Conclusion Control of the working environment and adequate sleep are decisive and protective factors in dealing with situations of occupational stress.

  13. Expression of Endoplasmic Reticulum Stress-Related Factors in the Retinas of Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Shu Yan

    2012-01-01

    Full Text Available Recent reports show that ER stress plays an important role in diabetic retinopathy (DR, but ER stress is a complicated process involving a network of signaling pathways and hundreds of factors, What factors involved in DR are not yet understood. We selected 89 ER stress factors from more than 200, A rat diabetes model was established by intraperitoneal injection of streptozotocin (STZ. The expression of 89 ER stress-related factors was found in the retinas of diabetic rats, at both 1- and 3-months after development of diabetes, by quantitative real-time polymerase chain reaction arrays. There were significant changes in expression levels of 13 and 12 ER stress-related factors in the diabetic rat retinas in the first and third month after the development of diabetes, Based on the array results, homocysteine- inducible, endoplasmic reticulum stress-inducible, ubiquitin-like domain member 1(HERP, and synoviolin(HRD1 were studied further by immunofluorescence and Western blot. Immunofluorescence and Western blot analyses showed that the expression of HERP was reduced in the retinas of diabetic rats in first and third month. The expression of Hrd1 did not change significantly in the retinas of diabetic rats in the first month but was reduced in the third month.

  14. Sigma-2 receptor ligands QSAR model dataset

    Directory of Open Access Journals (Sweden)

    Antonio Rescifina

    2017-08-01

    Full Text Available The data have been obtained from the Sigma-2 Receptor Selective Ligands Database (S2RSLDB and refined according to the QSAR requirements. These data provide information about a set of 548 Sigma-2 (σ2 receptor ligands selective over Sigma-1 (σ1 receptor. The development of the QSAR model has been undertaken with the use of CORAL software using SMILES, molecular graphs and hybrid descriptors (SMILES and graph together. Data here reported include the regression for σ2 receptor pKi QSAR models. The QSAR model was also employed to predict the σ2 receptor pKi values of the FDA approved drugs that are herewith included.

  15. LEAN SIX SIGMA – MULTIPLE CASE STUDY

    Directory of Open Access Journals (Sweden)

    Delvio Venanzi

    2017-12-01

    Full Text Available Lean Six Sigma é uma gestão focada na qualidade e desempenho produtivo em sistemas operacionais. Este artigo discute os fundamentos desta metodologia através de duas diferentes concepções de gestão, Lean Manufacturing e Six Sigma. Primeiro, o artigo explica o DMAIC (definir, medir, analisar, melhorar e controlar e suas respectivas fases, após a filosofia Lean com o sipoc e técnicas de mapeamento de fluxo de valor. O artigo pretende mostrar a integração destes dois conceitos e seus resultados. A metodologia consistiu em uma teoria baseada em uma pesquisa bibliográfica de pesquisa exploratória que consistiu de três estudos de caso em empresas de diferenças localizadas em Sorocaba, São Paulo. Neste artigo estuda a aplicação de Lean Seis Sigma e seus resultados.

  16. Lattice sigma models with exact supersymmetry

    International Nuclear Information System (INIS)

    Simon Catterall; Sofiane Ghadab

    2004-01-01

    We show how to construct lattice sigma models in one, two and four dimensions which exhibit an exact fermionic symmetry. These models are discretized and twisted versions of conventional supersymmetric sigma models with N=2 supersymmetry. The fermionic symmetry corresponds to a scalar BRST charge built from the original supercharges. The lattice theories possess local actions and exhibit no fermion doubling. In the two and four dimensional theories we show that these lattice theories are invariant under additional discrete symmetries. We argue that the presence of these exact symmetries ensures that no fine tuning is required to achieve N=2 supersymmetry in the continuum limit. As a concrete example we show preliminary numerical results from a simulation of the O(3) supersymmetric sigma model in two dimensions. (author)

  17. Six Sigma Driven Enterprise Model Transformation

    Directory of Open Access Journals (Sweden)

    Raymond Vella

    2009-10-01

    Full Text Available Enterprise architecture methods provide a structured system to understand enterprise activities. However, existing enterprise modelling methodologies take static views of the enterprise and do not naturally lead to a path of improvement during enterprise model transformation. This paper discusses the need for a methodology to facilitate changes for improvement in an enterprise. The six sigma methodology is proposed as the tool to facilitate progressive and continual Enterprise Model Transformation to allow businesses to adapt to meet increased customer expectation and global competition. An alignment of six sigma with phases of GERAM life cycle is described with inclusion of Critical-To-Satisfaction (CTS requirements. The synergies of combining the two methodologies are presented in an effort to provide a more culturally embedded framework for Enterprise Model Transformation that builds on the success of six sigma.

  18. Prevalence and associated factors of stress, anxiety and depression ...

    African Journals Online (AJOL)

    Background: Mental health issues are increasing in severity and number on college campuses. Improving adolescent mental well-being remains a challenge for most societies. Objectives: The objectives of this study was to study the prevalence of psychological mood disorders and its association with some factors.

  19. Brain-derived neurotrophic factor and early-life stress

    Indian Academy of Sciences (India)

    2016-10-24

    Oct 24, 2016 ... The brain-derived neurotrophic factor (BDNF) is a key regulator of neural development and ... forms are produced by splicing individual non-coding ..... VII and. IX m. RNA. ↑. mBDNF. ↓. (MS). 5. BDNF expression was unch;.

  20. Factors associated with recurrent fifth metatarsal stress fracture.

    Science.gov (United States)

    Lee, Kyung-tai; Park, Young-uk; Jegal, Hyuk; Kim, Ki-chun; Young, Ki-won; Kim, Jin-su

    2013-12-01

    Many surgeons agree that fifth metatarsal stress fractures have a tendency toward delayed union, nonunion, and possibly refracture. Difficulty healing seems to be correlated with fracture classification. However, refracture sometimes occurs after low-grade fracture, even long after apparent resolution. The records of 168 consecutive cases of fifth metatarsal stress fracture (163 patients) treated by modified tension band wiring from March 2002 to June 2011 were evaluated retrospectively. Mean length of follow-up was 23.6 months (range, 10-112 months). Forty-nine cases classified as Torg III were bone grafted initially also. All enrolled patients were elite athletes. Eleven patients experienced nonunion and 18 refracture. The 11 nonunion cases were bone grafted. The 157 patients (excluding nonunion cases) were allocated to either a refracture group or a union group. Clinical features, such as age, weight, fracture classification, time to union, and reinjury history, were compared. Radiological parameters representing cavus deformity and fifth metatarsal head protrusion were compared to evaluate the influence of structural abnormalities. Mean group weights were significantly different (P = .041), but mean ages (P = .879), fracture grades (P = .216, P = .962), and time from surgery to rehabilitation (P = .539) were similar. No significant intergroup differences were found for talocalcaneal (TC) angle (P = .470), calcaneal pitch (CP) angle (P = .847), or talo-first metatarsal (T-MT1) angle (P = .407) on lateral radiographs; for fifth metatarsal lateral deviation (MT5-LD) angle (P = .623) on anteroposterior (AP) radiographs; or for MT5-LD angle (P = .065) on the 30-degree medial oblique radiographs. However, the mean fourth-fifth intermetatarsal (IMA4-5) angle on AP radiographs was significantly greater in the refracture group, and for Torg II cases, mean weight (P = .042), IMA4-5 angle on AP radiographs (P = .014), and MT5-LD angle (P = .043) on 30-degree medial

  1. The Impact of Lean Six Sigma on the Overall Results of Companies

    Directory of Open Access Journals (Sweden)

    Corina DUMITRESCU

    2011-12-01

    Full Text Available Lean Six Sigma represents a management approach for driving innovating processes inside a company in order to achieve superior results. It involves a practical analysis based on facts, aiming the innovation and growth, not only the efficiency of processes. It is a long term process of gradual and continuous improvement. The application of Lean Six Sigma in companies led to attaining superior financial performance by addressing new needs, by differentiating the products and services or by adjusting the business lines to new processes. Quality is more than making things without errors. It is about making a product or service meet the individual perception of a customer about the quality or value. Therefore, in what regards Lean Six Sigma, the concern is not only to "do the things right" but also to "do the right things right". We focus on the impact of implementing the Lean Six Sigma approach on companies, seeking for what changes and benefits it brings. The key elements it aims at are achieving the best quality, the lowest cost, getting the shortest lead-time, stressing on waste elimination. The requirements of a company for its implementation and the strategy to obtain the maximum practical outcome are investigated. Furthermore, we conduct a comparison analysis with the other methods of the total quality management and see why Lean Six Sigma is a more desirable approach.

  2. Stress-driven grain growth

    CSIR Research Space (South Africa)

    Nabarro, FRN

    1998-11-13

    Full Text Available of length b (1+ epsilon) is parallel to sigma, embedded in a grain in which the lattice vector b (1+ epsilon) is transverse to sigma. If the embedded grain grows at the expense of its matrix, the source of the stress will do work, and therefore the presence...

  3. Problem-solving skills and hardiness as protective factors against stress in Iranian nurses.

    Science.gov (United States)

    Abdollahi, Abbas; Talib, Mansor Abu; Yaacob, Siti Nor; Ismail, Zanariah

    2014-02-01

    Nursing is a stressful occupation, even when compared with other health professions; therefore, it is necessary to advance our knowledge about the protective factors that can help reduce stress among nurses. The present study sought to investigate the associations among problem-solving skills and hardiness with perceived stress in nurses. The participants, 252 nurses from six private hospitals in Tehran, completed the Personal Views Survey, the Perceived Stress Scale, and the Problem-Solving Inventory. Structural Equation Modeling (SEM) was used to analyse the data and answer the research hypotheses. As expected, greater hardiness was associated with low levels of perceived stress, and nurses low in perceived stress were more likely to be considered approachable, have a style that relied on their own sense of internal personal control, and demonstrate effective problem-solving confidence. These findings reinforce the importance of hardiness and problem-solving skills as protective factors against perceived stress among nurses, and could be important in training future nurses so that hardiness ability and problem-solving skills can be imparted, allowing nurses to have more ability to control their perceived stress.

  4. A Lean Six Sigma journey in radiology.

    Science.gov (United States)

    Bucci, Ronald V; Musitano, Anne

    2011-01-01

    The department of radiology at Akron Children's Hospital embarked on a Lean Six Sigma mission as part of a hospital wide initiative to show increased customer satisfaction, reduce employee dissatisfaction and frustration, and decrease costs. Three processes that were addressed were reducing the MRI scheduling back-log, reconciling discrepancies in billing radiology procedures, and implementing a daily management system. Keys to success is that managers provide opportunities to openly communicate between department sections to break down barriers. Executive leaders must be engaged in Lean Six Sigma for the company to be successful.

  5. Supersymmetric sigma models and the heterotic string

    International Nuclear Information System (INIS)

    Hull, C.M.; Witten, E.

    1989-01-01

    The authors define the (1 + 1)-dimensional supersymmetry algebra of type (p, q) to be that generated by p right-handed Majorana-Weyl supercharges and q left-handed ones. They construct the non-linear sigma models with supersymmetry of type (1, 0) and (2, 0) and discuss their geometry and their relevance to compactifications of the heterotic superstring. The sigma-model anomalies can be canceled by a mechanism closely related to that used by Green and Schwarz to cancel gravitational and Yang-Mills anomalies for the superstring

  6. 6 Sigma DFSS technique with easy practice

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-12-15

    This book describes 6 Sigma DFSS technique which is easy to use. These are the titles of the contents : new demand, the reason that DFSS needs, when is DFSS used?, DMAIC and DMADV and the bastion for achievement of 6 sigma, new trouble, chief, Chang's new store, plan on kalguksu development propel, customers are holding the key, CTQ refinement, process capability evaluation, setting goal, finding of conception of optimum design, finding of design element, the last gateway, and it's time for a DFSS!.

  7. Stressful situations and factors in students of nursing in clinical practice

    Directory of Open Access Journals (Sweden)

    Eliana Ofélia Llapa Rodrigues

    Full Text Available Objective.To assess the risk factors for stress in undergraduate students of nursing in clinical practice in a public university in the Northeast region of Brazil. Methods. Cross-sectional descriptive study with 116 students from the fifth to the ninth period. The bilingual KEZKAK questionnaire, validated for Portuguese, was used. Stress was considered to be present when the score was equal or superior to 2. Results. The students with stress in clinical practice were 18 to 22 years old (2.82 ± 0.98, women (2.81 ± 0.96, married (2.80 ± 0.97, and who were permanent contracted employees (2.74 ± 0.94. The factors which were most associated with stress were: Lack of competence (2.99 ± 0.88; Impotence and uncertainty (2.98 ± 0.85; and Patients seeking a closer relationship (2.93 ± 1.01. The students of the sixth period were the most vulnerable to stress (2.85±0.96. Conclusion. The studies showed the main risk factors for stress among students of nursing in their clinical practice. These results could be used in the development of strategies seeking to reduce stress in this context as well as to contribute to promoting mental health.

  8. Stress Factors Associated With Burnout Among Attending Physicians: A Cross-Sectional Study.

    Science.gov (United States)

    Kawamura, Yurika; Takayashiki, Ayumi; Ito, Makoto; Maeno, Takami; Seo, Emiko; Maeno, Tetsuhiro

    2018-03-01

    Burnout in attending physicians is a crucial issue that may negatively impact patient outcomes, as well as affect the quality of training provided to residents. To investigate the association between burnout and stress-coping ability, we conducted a cross-sectional study of attending physicians. From April 2013 to March 2014, we distributed an anonymous, self-administered questionnaire to 1,897 attending physicians who attended teaching-related training sessions and workshops. The questionnaire included the Maslach Burnout Inventory General Survey (MBI-GS, Japanese version) to evaluate burnout; the sense of coherence scale (SOC, Japanese version) to measure stress-coping ability, with higher scores indicating higher stress-coping ability; the Brief Scales for Job Stress (BSJS) to assess stress and buffering factors; demographic factors; mean weekly working hours; and factors related to instructing residents. The MBI-GS was used to determine the presence of physician burnout. Subjects were divided into tertiles based on SOC scores. We conducted logistic regression analysis of burnout using the following independent variables: physician experience, sex, mean weekly working hours, SOC group, mental workload, and reward from work. Of the 1,543 (81.3%) attending physicians who responded, 376 did not meet the inclusion criteria and 106 had missing data, thus 1,061 (55.9%) were analyzed. The prevalence of burnout was 17.2%. Physicians with burnout had significantly fewer years of experience as a doctor (P burnout. On the BSJS, the mean score of all stress factors was higher and that of buffering factors was lower in physicians with burnout (P burnout were 35.7%, 12.8%, and 3.2% in the low, middle, and high SOC groups, respectively (P burnout in the low SOC group was 4.7 (95% confidence interval: 2.31 - 9.63) (P burnout among attending physicians was significantly associated with SOC scores after adjustment for stress factors and buffering factors.

  9. Job stress and its related factors in Tehran firefighters in year 2000

    Directory of Open Access Journals (Sweden)

    Yazdi SM

    2001-11-01

    Full Text Available Job stress results from a mismatch between job requirements and capabilities, resources, or needs of the worker. Physiological, psychological and behavioral outcomes caused by job stress not only hurt the person but also impose expensive costs on organizations. Firefighting is a job that exposes workers to job stress. The purpose of this study is to determine the level of job stress and some related factors in firefighters of Tehran safety services and firefighters organization. This cross sectional study includes 155 male firefighters whom had selected randomly. In this research we used Leiden University Questionnaire. Also Karasek Questionnaire is used for classification of workers according to karasek’s model. Collected data were analyzed by spss9 software. The final grade of firefighter’s job stress shows a significant positive relationship with second job and a significant negative relationship with age. The level of job satisfaction have a significant negative relationship with job insecurity and lack of meaningfulness, and a significant positive relationship with skill discretion, social support supervisor and social support co-workers. According to karasek classification this job is grouped in active not in high strain grup. The highest level of job stress was seen in physical exertion and hazardous exposure factors. Also in work and time pressure factor, job stress level is high. But job stress is in a moderate or low level in other factors. The level of job stress in younger firefighters and in individuals with a second job indicate a significant increase. However, in western country’s studies, this job is classified as high-strain but in this research it is classified as active group.

  10. Obesity-induced endoplasmic reticulum stress suppresses nuclear factor-Y expression.

    Science.gov (United States)

    Liu, Yulan; Zhang, Yuwei; Zhang, Yanjie; Zhang, Jinlong; Liu, Yin; Feng, Peiqun; Su, Zhiguang

    2017-02-01

    Nuclear transcription factor Y (NF-Y) is an evolutionarily conserved transcription factor composed of three subunits, NF-YA, NF-YB, and NF-YC. NF-Y plays crucial roles in pre-adipocyte maintenance and/or commitment to adipogenesis. NF-YA dysfunction in adipocyte resulted in an age-dependent progressive loss of adipose tissue associated with metabolic complications. Endoplasmic reticulum (ER) stress has emerged as an important mediator in the pathogenesis of obesity. However, it is not known if NF-YA is involved in the ER stress-mediated pathogenesis of obesity. We first examined the effects of ER stress on the NF-YA expression in cultured 3T3-L1 adipocytes; then in ob/ob genetic obesity mice, we tested the effect of chemical chaperones alleviating ER stress on the expression levels of NF-YA. Subsequently, we inhibited the new mRNA synthesis using actinomycin D in 3T3-L1 cells to explore the mechanism modulating NF-YA expression. Finally, we evaluated the involvement of PPARg in the regulation of NF-YA expression by ER stress. We demonstrated that both obesity- and chemical chaperone -induced ER stress suppressed NF-YA expression and alleviation of ER stress by chemical chaperone could recover NF-YA expression in ob/ob mice. Moreover, we showed that ER stress suppressed NF-YA mRNA transcription through the involvement of peroxisome proliferator-activated receptor gamma (PPARg). Activation of PPARg ameliorates the ER stress-induced NF-YA suppression. Our findings may point to a possible role of NF-YA in stress conditions that occur in chronic obesity, ER stress might be involved in the pathogenesis of obesity through NF-YA depletion.

  11. Risk Factors for Preschool Depression: The Mediating Role of Early Stressful Life Events

    Science.gov (United States)

    Luby, Joan L.; Belden, Andy C.; Spitznagel, Edward

    2006-01-01

    Background: Family history of mood disorders and stressful life events are both established risk factors for childhood depression. However, the role of mediators in risk trajectories, which are potential targets for intervention, remains understudied. To date, there have been no investigations of mediating relationships between risk factors and…

  12. Determining Factors for Stress Perception Assessed with the Perceived Stress Scale (PSS-4) in Spanish and Other European Samples.

    Science.gov (United States)

    Vallejo, Miguel A; Vallejo-Slocker, Laura; Fernández-Abascal, Enrique G; Mañanes, Guillermo

    2018-01-01

    Objective: Stress perception depends on cultural and social aspects that vary from one country to another. One of the most widely disseminated methods of assessing psychological stress is the Perceived Stress Scale (PSS-4). Therefore, in order to identify these factors and their impact on mental health, the present study compares the PSS-4 results among three European countries (Great Britain, France and Spain). This study focuses on PSS-4 results within a Spanish sample to determine: (1) normative data, reliability and validity of PSS-4 in a Spanish sample and (2) how stress perception changes depending on cultural and social factors. Methods: The data were obtained from a website representing a service of a smoking cessation program, the study represented a service that was open to all individuals. The number of participants were 37,451. They reported their age, gender, nationality, marital status, education and employment status, and completed two psychological questionnaires (PPS-4 and the anxiety and depression scales of the Symptom Checklist-90-Revised, SCL 90-R). Results: The PSS-4 scores could differentiate between relevant sociodemographic variables (such as sex, age, nationality, marital status, education, parental status, employment status, and income class). The PSS-4 scores showed a positive correlation with the SCL 90-R anxiety and depression scales. The normed values for interpreting the PSS-4 scores are presented. The PSS-4 showed adequate internal consistency and reliability. Conclusions: The PSS-4 is a useful instrument for assessing stress perception levels in the general population in different countries. Its internal consistency is sufficient for a 4-item scale.

  13. Determining Factors for Stress Perception Assessed with the Perceived Stress Scale (PSS-4 in Spanish and Other European Samples

    Directory of Open Access Journals (Sweden)

    Miguel A. Vallejo

    2018-01-01

    Full Text Available Objective: Stress perception depends on cultural and social aspects that vary from one country to another. One of the most widely disseminated methods of assessing psychological stress is the Perceived Stress Scale (PSS-4. Therefore, in order to identify these factors and their impact on mental health, the present study compares the PSS-4 results among three European countries (Great Britain, France and Spain. This study focuses on PSS-4 results within a Spanish sample to determine: (1 normative data, reliability and validity of PSS-4 in a Spanish sample and (2 how stress perception changes depending on cultural and social factors.Methods: The data were obtained from a website representing a service of a smoking cessation program, the study represented a service that was open to all individuals. The number of participants were 37,451. They reported their age, gender, nationality, marital status, education and employment status, and completed two psychological questionnaires (PPS-4 and the anxiety and depression scales of the Symptom Checklist-90-Revised, SCL 90-R.Results: The PSS-4 scores could differentiate between relevant sociodemographic variables (such as sex, age, nationality, marital status, education, parental status, employment status, and income class. The PSS-4 scores showed a positive correlation with the SCL 90-R anxiety and depression scales. The normed values for interpreting the PSS-4 scores are presented. The PSS-4 showed adequate internal consistency and reliability.Conclusions: The PSS-4 is a useful instrument for assessing stress perception levels in the general population in different countries. Its internal consistency is sufficient for a 4-item scale.

  14. Evaluation of Stress-Inducing Factors of Educational Environment in Hamadan Dentistry School’s Students

    Directory of Open Access Journals (Sweden)

    M. Dalband

    2007-01-01

    Full Text Available ntroduction & Objective: The aim of this study was to evaluate stressor factors of educational environment in Hamadan dental school’s students in year 2002.Materials & Methods: The study design was descriptive, cross-sectional and it was accomplished using a questionnaire which was taken from DES (dental environment stress questionnaire. According to restricted number of statistical population all members of population (154 students were evaluated as samples and this study was a survey one. Results: The results of this study indicated that most stressfull factors in dental students has been related to class work with mean score 3.18±0.83 and faculty-student relationship with mean score 3.05±0.83. Female students showed more total stress than male students (2.73 vs. 2.44. The fourth-year students had the most stress rate in all students of different years (3.05 and preclinical and clinical factors were the most stress-inducing factors of these students (3.63.Conclusion: It is concluded that the environment of Hamadan dental school and the process of education in the field of dentistry is potentially stressful. Also there is a reverse relationship between level of stress in students and their academic efficiencies.

  15. Resilience to chronic stress is mediated by hippocampal brain-derived neurotrophic factor.

    Science.gov (United States)

    Taliaz, Dekel; Loya, Assaf; Gersner, Roman; Haramati, Sharon; Chen, Alon; Zangen, Abraham

    2011-03-23

    Chronic stress is a trigger for several psychiatric disorders, including depression; however, critical individual differences in resilience to both the behavioral and the neurochemical effects of stress have been reported. A prominent mechanism by which the brain reacts to acute and chronic stress is activation of the hypothalamic-pituitary-adrenal (HPA) axis, which is inhibited by the hippocampus via a polysynaptic circuit. Alterations in secretion of stress hormones and levels of brain-derived neurotrophic factor (BDNF) in the hippocampus were implicated in depression and the effects of antidepressant medications. However, the potential role of hippocampal BDNF in behavioral resilience to chronic stress and in the regulation of the HPA axis has not been evaluated. In the present study, Sprague Dawley rats were subjected to 4 weeks of chronic mild stress (CMS) to induce depressive-like behaviors after lentiviral vectors were used to induce localized BDNF overexpression or knockdown in the hippocampus. The behavioral outcome was measured during 3 weeks after the CMS procedure, then plasma samples were taken for measurements of corticosterone levels, and finally hippocampal tissue was taken for BDNF measurements. We found that hippocampal BDNF expression plays a critical role in resilience to chronic stress and that reduction of hippocampal BDNF expression in young, but not adult, rats induces prolonged elevations in corticosterone secretion. The present study describes a mechanism for individual differences in responses to chronic stress and implicates hippocampal BDNF in the development of neural circuits that control adequate stress adaptations.

  16. Stress-related factors in cannabis use and misuse: implications for prevention and treatment.

    Science.gov (United States)

    Hyman, Scott M; Sinha, Rajita

    2009-06-01

    We examined the role of stress as a risk factor and motivation for cannabis use/misuse. A systematic review of studies gathered from PsychINFO and MEDLINE databases was conducted. Findings suggest that cannabis is commonly used as a stress-coping strategy. Negative life events, trauma, and maladaptive coping were all related to consumption. Cannabis use for stress-coping purposes was most evident when examining chronic as compared with experimental use. Although many individuals may be able to use cannabis without consequences, there appears to be a subset of individuals who experience greater life stress and who may be more likely to use for stress-coping purposes. These individuals may be at greatest risk for addiction. Chronic use may potentiate stress-related motivation to use/abuse cannabis and is associated with decision-making deficits and alterations in brain-stress pathways that may exacerbate compulsive drug seeking and sensitize individuals to stress-related drug use. Overall, stress-coping interventions and harm reduction focused on reducing the amount ingested may facilitate prevention and recovery efforts.

  17. Modelo de referência para estruturar o Seis Sigma nas organizações Reference model to structure the Six Sigma in organizations

    Directory of Open Access Journals (Sweden)

    Adriana Barbosa Santos

    2008-04-01

    Full Text Available Este artigo apresenta o modelo de referência para estruturar o Seis Sigma, o qual é resultante da incorporação de teorias que contribuem para aumentar o potencial estratégico do Seis Sigma no sentido de incrementar o desempenho organizacional. Em sua proposta, o modelo de referência engloba um direcionamento sobre certos requisitos primordiais para o sucesso do programa Seis Sigma. A base teórica de sustentação do modelo de referência foi construída a partir de estudos sobre a influência dos seguintes fatores: orientação estratégica e alinhamento estratégico; medição e gerenciamento do desempenho organizacional; uso de estatística (pensamento estatístico; capacitação/especialização de pessoas; implementação e gerenciamento de projetos; e uso de tecnologia de informação. Complementando a proposição do modelo, o artigo traz evidências empíricas acerca da contribuição dos fatores identificados na formulação do modelo de referência, expondo resultados decorrentes de estudos de caso realizados em quatro subsidiárias brasileiras de multinacionais de grande porte. A análise dos dados forneceu evidências positivas de que os fatores mencionados influenciam de forma efetiva o sucesso e a consolidação do Seis Sigma nas empresas estudadas.This paper introduces the reference model to structure Six Sigma. This model is a result of theory incorporation that contributes to increase the strategic power of Six Sigma for improving businesses performance. Reference model proposal points out certain primordial requirements for de Six Sigma program success. The theoretical basis to sustain the reference model was supported in studies about the influence of critical factors such as: strategic orientation and strategic alignment; business performance measurement; statistical approach (statistical thinking; people training; project implementation; and information technology use. Complementing the model proposition, this paper

  18. Chronic mild stress influences nerve growth factor through a matrix metalloproteinase-dependent mechanism.

    Science.gov (United States)

    Kucharczyk, Mateusz; Kurek, Anna; Detka, Jan; Slusarczyk, Joanna; Papp, Mariusz; Tota, Katarzyna; Basta-Kaim, Agnieszka; Kubera, Marta; Lason, Wladyslaw; Budziszewska, Bogusława

    2016-04-01

    Stress is generally a beneficial experience that motivates an organism to action to overcome the stressful challenge. In particular situations, when stress becomes chronic might be harmful and devastating. The hypothalamus is a critical coordinator of stress and the metabolic response; therefore, disruptions in this structure may be a significant cause of the hormonal and metabolic disturbances observed in depression. Chronic stress induces adverse changes in the morphology of neural cells that are often associated with a deficiency of neurotrophic factors (NTFs); additionally, many studies indicate that insufficient NTF synthesis may participate in the pathogenesis of depression. The aim of the present study was to determine the expression of the nerve growth factor (NGF) in the hypothalamus of male rats subjected to chronic mild stress (CMS) or to prenatal stress (PS) and to PS in combination with an acute stress event (AS). It has been found that chronic mild stress, but not prenatal stress, acute stress or a combination of PS with AS, decreased the concentration of the mature form of NGF (m-NGF) in the rat hypothalamus. A discrepancy between an increase in the Ngf mRNA and a decrease in the m-NGF levels suggested that chronic mild stress inhibited NGF maturation or enhanced the degradation of this factor. We have shown that NGF degradation in the hypothalamus of rats subjected to chronic mild stress is matrix metalloproteinase-dependent and related to an increase in the active forms of some metalloproteinases (MMP), including MMP2, MMP3, MMP9 and MMP13, while the NGF maturation process does not seem to be changed. We suggested that activated MMP2 and MMP9 potently cleave the mature but not the pro- form of NGF into biologically inactive products, which is the reason for m-NGF decomposition. In turn, the enhanced expression of Ngf in the hypothalamus of these rats is an attempt to overcome the reduced levels of m-NGF. Additionally, the decreased level of m

  19. Implementation of Lean Six Sigma in small- and medium-sized manufacturing enterprises in the Netherlands

    NARCIS (Netherlands)

    Timans, W.; Antony, J.; Ahaus, K.; van Solingen, R.

    In this paper we provide an exploration and analysis of Lean Six Sigma (LSS) implementation in Dutch manufacturing/engineering small- and medium-sized enterprises (SMEs). Critical success factors (CSFs) and impeding factors are identified and analysed. Exploratory empirical evidence about LSS

  20. Role of Stress Factors on the Adhesion of Interfaces in R2R Fabricated Organic Photovoltaics

    DEFF Research Database (Denmark)

    Corazza, Michael; Rolston, Nicholas; Dauskardt, Reinhold H.

    2016-01-01

    adhesion properties. Depth profiling analysis on the fractured samples reveals interdiffusion of layers in the structure, which results in the increase of adhesion and change of the debond path. It is shown that through diffusion and intermixing of internal interfaces coupled stresses can increase......The role of the common stress factors such as high temperature, humidity,and UV irradiation on interface adhesion of roll-to-roll fabricated organic photovoltaic (OPV) devices is investigated. The samples range from bare front electrodes to complete devices. It is shown that applying single stress...... or combinations of stresses onto the samples variably affect the adhesion properties of the different interfaces in the OPV device. It is revealed that while the exposure of the complete devices to the stresses results in the loss of photovoltaic performance, some interfaces in the devices present improved...

  1. Structure, function and networks of transcription factors involved in abiotic stress responses

    DEFF Research Database (Denmark)

    Lindemose, Søren; O'Shea, Charlotte; Jensen, Michael Krogh

    2013-01-01

    Transcription factors (TFs) are master regulators of abiotic stress responses in plants. This review focuses on TFs from seven major TF families, known to play functional roles in response to abiotic stresses, including drought, high salinity, high osmolarity, temperature extremes...... and the phytohormone ABA. Although ectopic expression of several TFs has improved abiotic stress tolerance in plants, fine-tuning of TF expression and protein levels remains a challenge to avoid crop yield loss. To further our understanding of TFs in abiotic stress responses, emerging gene regulatory networks based...... on TFs and their direct targets genes are presented. These revealed components shared between ABA-dependent and independent signaling as well as abiotic and biotic stress signaling. Protein structure analysis suggested that TFs hubs of large interactomes have extended regions with protein intrinsic...

  2. [Labour factors associated with post-traumatic stress in uniformed workers in Medellín].

    Science.gov (United States)

    González-Penagos, Catalina; Moreno-Bedoya, Juan P; Berbesi-Fernández, Dedsy Y; Segura-Cardona, Angela M

    2013-01-01

    Determining the labor factors associated with post-traumatic stress in uniformed workers in Medellin. A cross-sectional study was made of 124 uniformed workers aged 20 to 48 years-old. A survey was made using an adults' post-traumatic stress instrument which had been validated in Medellin. Statistical analysis was carried out. Post-traumatic stress disorder risk prevalence was 52.2 %. Multivariate analysis showed that the highest risk situations were those related to previous mental health diagnosis (PR=7.67), working schedule (4.24), violent episodes (PR=3.59) and community relationships (PR=2.73). A person's current labor situation seemed to be a risk factor for developing post-traumatic stress in the target population.

  3. Associations of oxidative stress status parameters with traditional cardiovascular disease risk factors in patients with schizophrenia.

    Science.gov (United States)

    Vidović, Bojana; Stefanović, Aleksandra; Milovanović, Srđan; Ðorđević, Brižita; Kotur-Stevuljević, Jelena; Ivanišević, Jasmina; Miljković, Milica; Spasić, Slavica

    2014-04-01

    The purpose of this study was to assess oxidative stress status parameters and their possible associations with traditional cardiovascular risk factors in patients with schizophrenia, as well as their potential for patient-control discrimination. Fasting glucose, lipid profile and oxidative stress status parameters were assessed in 30 schizophrenic patients with atypical antipsychotic therapy and 60 control subjects. Malondialdehyde (MDA), pro-oxidant/antioxidant balance (PAB) and total anti-oxidant status (TAS) were significantly higher whereas total sulfhydryl (SH) groups were significantly lower in schizophrenic patients vs. control group. Higher serum PAB values showed an independent association with schizophrenia. The addition of PAB to conventional risk factors improved discrimination between healthy control subjects and patients. Increased oxidative stress and changed lipid profile parameters are associated in schizophrenic patients and may indicate risk for atherosclerosis. The serum PAB level may reflect the levels of oxidative stress in schizophrenia and improve discrimination of patients from controls.

  4. Urban social stress – Risk factor for mental disorders. The case of schizophrenia

    International Nuclear Information System (INIS)

    Lederbogen, Florian; Haddad, Leila; Meyer-Lindenberg, Andreas

    2013-01-01

    Living in an urban environment is associated with an increased prevalence of specific mental health disorders, particularly schizophrenia. While many factors have been discussed as possible mediators of this association, most researchers favour the hypothesis that urban living stands as a proxy for an increased exposure to social stress. This factor has been recognized as one of the most powerful causes for the development of mental disorders, and appears to correlate with the markedly increased incidence of schizophrenia in urban minority groups. However, the hypothesis that the general urban population is exposed to increased levels of social stress has to be validated. Pursuing the goal of understanding how social stress acts as a risk factor for mental disorder in urban populations must include factors like social conditions, environmental pollutants, infrastructure and economic issues. -- Highlights: • City living is associated with an increased prevalence of mental health disorders, particularly schizophrenia. • Possible mediators of this association include exposure to social stress. • This mechanism seems plausible in urban minority groups. • However, it is unclear whether social stress exposure is increased in the general urban population. -- New data support the hypothesis that increased exposure to social stressors is a key factor mediating the increased prevalence of specific mental disorders in urban populations

  5. Dominant Repression by Arabidopsis Transcription Factor MYB44 Causes Oxidative Damage and Hypersensitivity to Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Helene Persak

    2014-02-01

    Full Text Available In any living species, stress adaptation is closely linked with major changes of the gene expression profile. As a substrate protein of the rapidly stress-induced mitogen-activated protein kinase MPK3, Arabidopsis transcription factor MYB44 likely acts at the front line of stress-induced re-programming. We recently characterized MYB44 as phosphorylation-dependent positive regulator of salt stress signaling. Molecular events downstream of MYB44 are largely unknown. Although MYB44 binds to the MBSII element in vitro, it has no discernible effect on MBSII-driven reporter gene expression in plant co-transfection assays. This may suggest limited abundance of a synergistic co-regulator. MYB44 carries a putative transcriptional repression (Ethylene responsive element binding factor-associated Amphiphilic Repression, EAR motif. We employed a dominant repressor strategy to gain insights into MYB44-conferred stress resistance. Overexpression of a MYB44-REP fusion markedly compromised salt and drought stress tolerance—the opposite was seen in MYB44 overexpression lines. MYB44-mediated resistance likely results from induction of tolerance-enhancing, rather than from repression of tolerance-diminishing factors. Salt stress-induced accumulation of destructive reactive oxygen species is efficiently prevented in transgenic MYB44, but accelerated in MYB44-REP lines. Furthermore, heterologous overexpression of MYB44-REP caused tissue collapse in Nicotiana. A mechanistic model of MAPK-MYB-mediated enhancement in the antioxidative capacity and stress tolerance is proposed. Genetic engineering of MYB44 variants with higher trans-activating capacity may be a means to further raise stress resistance in crops.

  6. A study of job stress and burnout and related factors in the hospital personnel of Iran

    Science.gov (United States)

    Abarghouei, Mohammad Reza; Sorbi, Mohammad Hossein; Abarghouei, Mehdi; Bidaki, Reza; Yazdanpoor, Shirin

    2016-01-01

    Introduction Job stress has become one of the main factors in reducing efficiency and the loss of human resources that may cause physical and psychological adverse effects in employees. Hospital personnel are facing different stressful events, such as birth, pain and death, in a single day. Hence, identifying the job stress rates and related factors may be effective in offering proper strategies. Therefore, the present research was done to study the rate of job stress and burnout in hospital personnel and compare some of the related factors in hospitals personnel of Yazd, Iran. Methods This cross-sectional study was conducted on 306 hospital personnel (Male: 114, Female: 192) in Yazd in 2015–16. The data were collected using a demographic questionnaire, Maslach Burnout Inventory (MBI), and Hospital Stress (HSS-35). SPSS-16 software and Pearson-product moment correlation and independent-samples t-test were used for data analysis. Results The mean job stress score was above average. The mean burnout dimensions that were above average included emotional exhaustion (21.7 ± 7.27), depersonalization (9.61 ± 3.74) and personal accomplishment (26.80 ± 6.17). While Pearson correlation revealed a significant positive relationship between job stress, emotional exhaustion, and depersonalization, there was a negative relationship between job stress and personal accomplishment (p hospital personnel is worrying and it has adverse effects on personnel health, effective strategies on physical and mental health, such as employment support and stress management training, seem crucial to enhance physical and psychological health of hospital personnel. PMID:27648189

  7. Maass waveforms arising from sigma and related indefinite theta functions

    OpenAIRE

    Zwegers, Sander

    2010-01-01

    In this paper we consider an example of a Maass waveform which was constructed by Cohen from a function $\\sigma$, studied by Andrews, Dyson and Hickerson, and it's companion $\\sigma^*$. We put this example in a more general framework.

  8. Study of the variations in apoptotic factors in hippocampus of male rats with posttraumatic stress disorder

    Directory of Open Access Journals (Sweden)

    Behrang Alani

    2013-01-01

    Full Text Available Background: Post-traumatic stress disorder (PTSD is a stress-related psychosomatic disorder caused by occurrence of a traumatic event and the hippocampus volume of the patients with Post-traumatic stress disorder decreased. However, the mechanisms that cause such damage are not well-understood. The aim of this study is to detect the expression of apoptosis-related Bax, Bcl-2, Caspase-3 and Insulin-like growth Factor-I proteins in the hippocampus region in the Predatory stress rats. Materials and Methods: A total of 70 male wistar rats were divided into Predatory stress groups of 1d, 2d, 3d, 7d, 14d, 30d and a normal control group (N = 10. Rats were subjected to 5 min of predatory stress and then exposed to the elevated plus-maze (EPM. Serum corticosterone and Insulin-like growth factor-1 level of Hippocampus were measured by ELISA technique. The expression of Bax, Bcl-2, and Caspase-3 were detected by western blotting. Results: Rats spent significantly more time in closed arms of the elevated plus maze (EPM than control group after exposure to stress. Serum levels of corticosterone significantly increased at 2d-3d. The expression of hippocampal IGF-1 was significantly up-regulated at 1d-2d after stress. Both Bax and the ratio of Bax/Bcl-2 significantly peaked at Predatory stress 2d-14d. Caspase3 was significantly active among 2d-30 compared to the normal control. Conclusion: The activation of caspase-3 in the stress groups indicates that apoptosis may be one of the reasons inducing hippocampus atrophy and play roles in the pathogenesis of PTSD. Increase in hippocampus levels of IGF-1 during early PTSD might be involved in the early molecular inhibitory mechanism of apoptosis in PTSD.

  9. Relationship between stress factor and periodontal disease in a rural area population in Japan

    OpenAIRE

    Akhter, Rahena; Hannan, MA; Okhubo, R; Morita, M

    2005-01-01

    Objectives: Several studies conducted in Western countries have shown significant associations between stress factors and periodontal disease. However, there have been only a few studies conducted in Asian countries. The present study was designed to identify possible relationship between stress and periodontal disease in residents of a rural area in Japan. Material and Methods: Data were collected from 1,089 adults with at least six natural teeth in a typical farming district of Japan. S...

  10. Predicting the change of child’s behavior problems: sociodemographic and maternal parenting stress factors

    OpenAIRE

    Viduolienė, Evelina

    2013-01-01

    Purpose: evaluate 1) whether child’s externalizing problems increase or decrease within 12 months period; 2) the change of externalizing problems with respect to child gender and age, and 3) which maternal parenting stress factors and family sociodemographic characteristics can predict the increase and decrease of child’s externalizing problems. Design/methodology/approach: participants were evaluated 2 times (with the interval of 12 months) with the Parenting Stress Index (Abidin, 1990) and ...

  11. Some examples of instantons in sigma models

    International Nuclear Information System (INIS)

    Kogan, Ya.; Markushevich, D.; Morozov, A.; Ol'shanetskij, M.; Perelomov, A.; Roslyj, A.

    1988-01-01

    Holomorphic instantons of arbitrary generation in manifolds and their boson and fermion zero modes are determined within the scope of the sigma model. General formulae for their quantitative evaluation are presented. Zero modes of spherical and toroidal instantons are discussed in detail

  12. Lean Six Sigma: Stap voor stap

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Koning, H.; de Mast, J.

    2008-01-01

    Lean Six Sigma is de culminatie van ontwikkelingen in kwaliteitsverbetering in de 20ste eeuw. Het combineert belangrijke principes en technieken in een goed gestructureerde en geïntegreerde benadering. Het belichaamt wetenschappelijke inzichten over onderzoeksmethodologie, management en economie. In

  13. Need of Six Sigma in Education

    Science.gov (United States)

    Mehrotra, Dheeraj

    2007-01-01

    The marching trend of the new economic order has generated a new capsule of SIX SIGMA as a unified approach to process excellence. The tests reveal that it has transformed some of the most successful companies in the world like Motorola, GE etc. It is activated as an approach to aiming at the target by changing the culture of a company, involving…

  14. Six Sigma and Introductory Statistics Education

    Science.gov (United States)

    Maleyeff, John; Kaminsky, Frank C.

    2002-01-01

    A conflict exists between the way statistics is practiced in contemporary business environments and the way statistics is taught in schools of management. While businesses are embracing programs, such as six sigma and TQM, that bring statistical methods to the forefront of management decision making, students do not graduate with the skills to…

  15. How Six Sigma Methodology Improved Doctors' Performance

    Science.gov (United States)

    Zafiropoulos, George

    2015-01-01

    Six Sigma methodology was used in a District General Hospital to assess the effect of the introduction of an educational programme to limit unnecessary admissions. The performance of the doctors involved in the programme was assessed. Ishikawa Fishbone and 5 S's were initially used and Pareto analysis of their findings was performed. The results…

  16. Implementing Lean Six Sigma in organizations

    NARCIS (Netherlands)

    Lameijer, B.A.

    2017-01-01

    This thesis focuses on operational excellence following the Lean Six Sigma (LSS) method. As the popularity of implementing LSS grows, questions about implementing LSS in organizations arise, and this is where we aim to contribute. We study key questions about implementing LSS in organizations at two

  17. Harmonicity in supermanifolds and sigma models

    International Nuclear Information System (INIS)

    Munoz-Masque, Jaime; Vallejo, Jose A.

    2009-01-01

    We show that given an odd metric G on a supermanifold (M, A) and its associated Laplacian Δ, it is possible to interpret harmonic superfunctions (i.e., those f is an element of A such that Δf = 0) as solutions to a variational problem describing a supersymmetric sigma model.

  18. Improving Learning Outcome Using Six Sigma Methodology

    Science.gov (United States)

    Tetteh, Godson A.

    2015-01-01

    Purpose: The purpose of this research paper is to apply the Six Sigma methodology to identify the attributes of a lecturer that will help improve a student's prior knowledge of a discipline from an initial "x" per cent knowledge to a higher "y" per cent of knowledge. Design/methodology/approach: The data collection method…

  19. Remarks on non compact sigma models

    International Nuclear Information System (INIS)

    Brunini, S.A.; Gomes, M.; Silva, A.J. da.

    1988-01-01

    O(N,1) noncompact sigma models quantized in an indefinite metric space. In two dimensions, by a direct computation the existence of a positive metric subspace where the S matrix is unitary. Is proved the properties of the model as function of the temperature are investigated in various space time dimensions. (author) [pt

  20. The Scientific Underpinning of Lean Six Sigma

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Mast, J.; de Koning, H.; Bisgaard, S.

    2007-01-01

    The twentieth century saw an incredible development of professional organizations. The impact of technological advances is obvious, but besides these, innovations in management structures and methods have resulted in the highly productive organizations of today. Lean Six Sigma is not revolutionary.

  1. Lean Six Sigma for Service and Healthcare

    NARCIS (Netherlands)

    de Mast, J.; Does, R.J.M.M.; de Koning, H.

    2006-01-01

    Lean Six Sigma is built on principles and methods that have proven themselves over the twentieth century. It has incorporated the most effective approaches and integrated them into a full programme. It offers a management structure for organizing continuous improvement of routine tasks, such as

  2. The brain-derived neurotrophic factor pathway, life stress, and chronic multi-site musculoskeletal pain.

    Science.gov (United States)

    Generaal, Ellen; Milaneschi, Yuri; Jansen, Rick; Elzinga, Bernet M; Dekker, Joost; Penninx, Brenda W J H

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) disturbances and life stress, both independently and in interaction, have been hypothesized to induce chronic pain. We examined whether (a) the BDNF pathway (val(66)met genotype, gene expression, and serum levels), (b) early and recent life stress, and (c) their interaction are associated with the presence and severity of chronic multi-site musculoskeletal pain. Cross-sectional data are from 1646 subjects of the Netherlands Study of Depression and Anxiety. The presence and severity of chronic multi-site musculoskeletal pain were determined using the Chronic Pain Grade (CPG) questionnaire. The BDNF val(66)met polymorphism, BDNF gene expression, and BDNF serum levels were measured. Early life stress before the age of 16 was assessed by calculating a childhood trauma index using the Childhood Trauma Interview. Recent life stress was assessed as the number of recent adverse life events using the List of Threatening Events Questionnaire. Compared to val(66)val, BDNF met carriers more often had chronic pain, whereas no differences were found for BDNF gene expression and serum levels. Higher levels of early and recent stress were both associated with the presence and severity of chronic pain (p stress in the associations with chronic pain presence and severity. This study suggests that the BDNF gene marks vulnerability for chronic pain. Although life stress did not alter the impact of BDNF on chronic pain, it seems an independent factor in the onset and persistence of chronic pain. © The Author(s) 2016.

  3. A classification of psychological factors leading to violent behavior in posttraumatic stress disorder.

    Science.gov (United States)

    Silva, J A; Derecho, D V; Leong, G B; Weinstock, R; Ferrari, M M

    2001-03-01

    Posttraumatic stress disorder has long been linked to violent behavior. However, the exact nature of that association remains poorly characterized due to the limitations of knowledge in the area of phenomenology, contextual factors, the biology, and the nature of the aggression involved in the disorder. A clear understanding of the genesis of violence in posttraumatic stress disorder can be helpful to those involved in assessing psychiatric-legal issues relevant to the disorder and in its therapeutic management. In this article, we review the potential psychological links between posttraumatic stress disorder secondary to combat exposure and violent behavior and suggest a tentative classification of the main psychological causes of violence in that syndrome.

  4. Stressful situations and factors in students of nursing in clinical practice

    OpenAIRE

    Llapa Rodrigues, Eliana Ofélia; Almeida Marques, Daniel; Lopes Neto, David; López Montesinos, María José; Amado de Oliveira, Adriana Sousa

    2016-01-01

    Objective.To assess the risk factors for stress in undergraduate students of nursing in clinical practice in a public university in the Northeast region of Brazil. Methods. Cross-sectional descriptive study with 116 students from the fifth to the ninth period. The bilingual KEZKAK questionnaire, validated for Portuguese, was used. Stress was considered to be present when the score was equal or superior to 2. Results. The students with stress in clinical practice were 18 to 22 years old (2.82 ...

  5. A prototypical Sigma-1 receptor antagonist protects against brain ischemia

    OpenAIRE

    Schetz, John A.; Perez, Evelyn; Liu, Ran; Chen, Shiuhwei; Lee, Ivan; Simpkins, James W.

    2007-01-01

    Previous studies indicate that the Sigma-1 ligand 4-phenyl-1-(4-phenylbutyl) piperidine (PPBP) protects the brain from ischemia. Less clear is whether protection is mediated by agonism or antagonism of the Sigma-1 receptor, and whether drugs already in use for other indications and that interact with the Sigma-1 receptor might also prevent oxidative damage due to conditions such as cerebral ischemic stroke. The antipsychotic drug haloperidol is an antagonist of Sigma-1 receptors and in this s...

  6. Genome wide analysis of stress responsive WRKY transcription factors in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Shaiq Sultan

    2016-04-01

    Full Text Available WRKY transcription factors are a class of DNA-binding proteins that bind with a specific sequence C/TTGACT/C known as W-Box found in promoters of genes which are regulated by these WRKYs. From previous studies, 43 different stress responsive WRKY transcription factors in Arabidopsis thaliana, identified and then categorized in three groups viz., abiotic, biotic and both of these stresses. A comprehensive genome wide analysis including chromosomal localization, gene structure analysis, multiple sequence alignment, phylogenetic analysis and promoter analysis of these WRKY genes was carried out in this study to determine the functional homology in Arabidopsis. This analysis led to the classification of these WRKY family members into 3 major groups and subgroups and showed evolutionary relationship among these groups on the base of their functional WRKY domain, chromosomal localization and intron/exon structure. The proposed groups of these stress responsive WRKY genes and annotation based on their position on chromosomes can also be explored to determine their functional homology in other plant species in relation to different stresses. The result of the present study provides indispensable genomic information for the stress responsive WRKY transcription factors in Arabidopsis and will pave the way to explain the precise role of various AtWRKYs in plant growth and development under stressed conditions.

  7. Stress, sex, and addiction: potential roles of corticotropin-releasing factor, oxytocin, and arginine-vasopressin.

    Science.gov (United States)

    Bisagno, Verónica; Cadet, Jean Lud

    2014-09-01

    Stress sensitivity and sex are predictive factors for the development of neuropsychiatric disorders. Life stresses are not only risk factors for the development of addiction but also are triggers for relapse to drug use. Therefore, it is imperative to elucidate the molecular mechanisms underlying the interactions between stress and drug abuse, as an understanding of this may help in the development of novel and more effective therapeutic approaches to block the clinical manifestations of drug addiction. The development and clinical course of addiction-related disorders do appear to involve neuroadaptations within neurocircuitries that modulate stress responses and are influenced by several neuropeptides. These include corticotropin-releasing factor, the prototypic member of this class, as well as oxytocin and arginine-vasopressin that play important roles in affiliative behaviors. Interestingly, these peptides function to balance emotional behavior, with sexual dimorphism in the oxytocin/arginine-vasopressin systems, a fact that might play an important role in the differential responses of women and men to stressful stimuli and the specific sex-based prevalence of certain addictive disorders. Thus, this review aims to summarize (i) the contribution of sex differences to the function of dopamine systems, and (ii) the behavioral, neurochemical, and anatomical changes in brain stress systems.

  8. Prenatal Stress as a Risk-and an Opportunity-Factor.

    Science.gov (United States)

    Hartman, Sarah; Freeman, Sara M; Bales, Karen L; Belsky, Jay

    2018-04-01

    Two separate lines of research indicate (a) that prenatal stress is associated with heightened behavioral and physiological reactivity and (b) that these postnatal phenotypes are associated with increased susceptibility to both positive and negative developmental experiences. Therefore, prenatal stress may increase sensitivity to the rearing environment. We tested this hypothesis by manipulating prenatal stress and rearing-environment quality, using a cross-fostering paradigm, in prairie voles. Results showed that prenatally stressed voles, as adults, displayed the highest behavioral and physiological reactivity when cross-fostered to low-contact (i.e., low-quality) rearing but the lowest behavioral and physiological reactivity when cross-fostered to high-contact (i.e., high-quality) rearing; non-prenatally stressed voles showed no effect of rearing condition. Additionally, while neither prenatal stress nor rearing condition affected oxytocin receptor binding, prenatally stressed voles cross-fostered to high-contact rearing showed the highest vasopressin-1a receptor binding in the amygdala. Results indicate that prenatal stress induces greater environmental sensitivity, making it both a risk and an opportunity factor.

  9. Childhood Cancer in Context: Sociodemographic Factors, Stress, and Psychological Distress Among Mothers and Children.

    Science.gov (United States)

    Bemis, Heather; Yarboi, Janet; Gerhardt, Cynthia A; Vannatta, Kathryn; Desjardins, Leandra; Murphy, Lexa K; Rodriguez, Erin M; Compas, Bruce E

    2015-09-01

    To examine associations between sociodemographic factors (single parenthood, family income, education level, race), stress, and psychological distress among pediatric cancer patients and their mothers. Participants completed measures assessing sociodemographic variables, depressive symptoms, posttraumatic stress symptoms, general stress, and cancer-related stress within the first year of the child's (ages 5-17 years) cancer diagnosis or relapse. Mothers (N = 318) provided self-reports and parent report of their children; children aged 10-17 years (N = 151) completed self-reports. Each sociodemographic variable demonstrated unique associations with mothers' and children's stress and distress in bivariate analyses. A cumulative sociodemographic risk measure was positively correlated with all stress and distress variables. In regression analyses predicting mothers' and children's distress, independent and cumulative sociodemographic measures were no longer significant when accounting for levels of stress. Findings highlight the need to consider the ecological context of pediatric cancer, particularly the impact of sociodemographic disadvantage on stress and distress in this population. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. The structure of the .sigma.-ideal of .sigma.-porous sets

    Czech Academy of Sciences Publication Activity Database

    Zelený, M.; Pelant, Jan

    2004-01-01

    Roč. 45, č. 1 (2004), s. 37-72 ISSN 0010-2628 R&D Projects: GA ČR GA201/97/1161; GA ČR GA201/97/0216; GA ČR GA201/00/1466; GA AV ČR KSK1019101 Institutional research plan: CEZ:AV0Z1019905 Keywords : .sigma. proposity * descriptive set theory * .sigma.-ideal Subject RIV: BA - General Mathematics

  11. Factor structure and validity of the Depression, Anxiety and Stress Scale-21 in Swedish translation.

    Science.gov (United States)

    Alfonsson, S; Wallin, E; Maathz, P

    2017-03-01

    WHAT IS KNOWN ON THE SUBJECT?: The Depression, Anxiety and Stress Scale-21 (DASS-21) is a widely used measurement for psychological symptoms and distress. Some previous studies have shown that the DASS-21 can accurately measure symptoms of anxiety, depression and stress, while other studies have indicated that the DASS-21 mainly measures overall distress. The factor structure of the DASS-21 is important and debated since if affects interpretations of findings. WHAT DOES THIS PAPER ADD TO EXISTING KNOWLEDGE?: In this study, the DASS-21 was translated into Swedish and evaluated in three diverse samples. The DASS-21 subscales of Depression and Anxiety correlated significantly with corresponding criteria instruments. The DASS-21 Stress subscale showed more diverse associations with psychological distress. The analyses supported a bifactor model of the DASS-21 with three specific factors of depression, anxiety and stress as well as a general distress factor. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: The results show that the DASS-21 may be used to measure unique symptoms of depression, anxiety and, with some caveat, stress as well as overall psychological distress. This study confirms that the DASS-21 is theoretically sound instrument that is feasible for both research and clinical practice. The DASS-21 can be an accessible tool for screening and evaluation in first-line mental health services. Introduction There is a constant need for theoretically sound and valid self-report instruments for measuring psychological distress. Previous studies have shown that the Depression, Anxiety and Stress Scale-21 (DASS-21) is theoretically sound, but there have been some inconsistent results regarding its factor structure. Aims The aim of the present study was to investigate and elucidate the factor structure and convergent validity of the DASS-21. Methods A total of 624 participants recruited from student, primary care and psychotherapy populations. The factor structure of the DASS

  12. Analysis of stress intensity factors for a new mechanical corrosion specimen

    International Nuclear Information System (INIS)

    Rassineux, B.; Crouzet, D.; Le Hong, S.

    1996-03-01

    Electricite de France is conducting a research program to determine corrosion cracking rates in the steam generators Alloy 600 tubes of the primary system. The objective is to correlate the cracking rates with the specimen stress intensity factor K I . One of the samples selected for the purpose of this study is the longitudinal notched specimen TEL (TEL: ''Tubulaire a Entailles Longitudinales''). This paper presents the analysis of the stress intensity factor and its experimental validation. The stress intensity factor has been evaluated for different loads using 3D finite element calculations with the Hellen-Parks and G(θ) methods. Both crack initiation and propagation are considered. As an assessment of the method, the numerical simulations are in good agreement with the fatigue crack growth rates measured experimentally for TEL and compact tension (CT) specimens. (authors). 8 refs., 6 figs., 2 tabs

  13. Mid-thickness studies of the stress intensity factor in the bulk of bainitic steel

    Directory of Open Access Journals (Sweden)

    P. Lopez-Crespo

    2017-07-01

    Full Text Available The current work aims at estimating the stress intensity factor deep inside the bulk from elastic strain data measured by synchrotron X-ray diffraction. Key features affecting the evaluation of the stress intensity factor are the number of terms in the analytical model describing the crack tip field, the extension and position of the area of interest of the experimental data, the effect of the experimental data collected within the plastic zone and the number of elastic strain data points used. Here a parametric study of these features is presented in terms of their influence for the stress intensity factor determination. It was found that 3 or 4 terms in Williams’ expansion is often sufficient; the data should be collected from across the full range of angles around the crack tip; and the number of points/number of terms should be greater than 40.

  14. Incorporating Six Sigma Methodology Training into Chemical Engineering Education

    Science.gov (United States)

    Dai, Lenore L.

    2007-01-01

    Six Sigma is a buzz term in today's technology and business world and there has been increasing interest to initiate Six Sigma training in college education. We have successfully incorporated Six Sigma methodology training into a traditional chemical engineering course, Engineering Experimentation, at Texas Tech University. The students have…

  15. Operational excellence (six sigma) philosophy: Application to software quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, M.

    1997-11-01

    This report contains viewgraphs on operational excellence philosophy of six sigma applied to software quality assurance. This report outlines the following: goal of six sigma; six sigma tools; manufacturing vs administrative processes; Software quality assurance document inspections; map software quality assurance requirements document; failure mode effects analysis for requirements document; measuring the right response variables; and questions.

  16. Commutative $C^*$-algebras and $\\sigma$-normal morphisms

    OpenAIRE

    de Jeu, Marcel

    2003-01-01

    We prove in an elementary fashion that the image of a commutative monotone $\\sigma$-complete $C^*$-algebra under a $\\sigma$-normal morphism is again monotone $\\sigma$-complete and give an application of this result in spectral theory.

  17. Occupational stress and its related factors among university teachers in China.

    Science.gov (United States)

    Sun, Wei; Wu, Hui; Wang, Lie

    2011-01-01

    University teachers in China are expected to suffer serious occupational stress due to the expanding enrollment in universities without a proportional increase in teacher resources and the fact that all promotions for university teachers are determined based on not only teaching but also the outcome of scientific research. This study was designed to assess the occupational stress among university teachers in China and clarify its risk factors. A cross-sectional study was performed in Liaoning Province, the centralized area of higher education in Northeast China. Eight universities (2 multidiscipline and 6 specialized) and 10% of academic staff each were randomly sampled. Questionnaires pertaining to occupational stress indicated by the Chinese Version Personal Strain Questionnaire (PSQ) and demographic characteristics, health status, work situations, and personal and social resources were distributed in October 2008. A total of 827 effective respondents (response rate 76.4%) became our participants. The average raw score of PSQ was 91.0 among the university teachers. General linear model analysis showed that the factors significantly associated with the PSQ score were, in standardized estimate (β) sequence, mental health, role overload, role insufficiency, social support, monthly income, role limitations due to physical problems, research finance and self-rated disease with adjustment for age and sex. We concluded that, in comparison to work-related factors and social support, mental health is a prominent risk factor for occupational stress in university teachers in China. Improvement of mental health and organizational climate should be considered to lessen the occupational stress of university teachers.

  18. Empirical research on the influencing factors of the occupational stress for construction workers

    Science.gov (United States)

    LV, Xing; WU, Xiang; CI, Huipeng; LIU, Qing; YAO, Yongzheng

    2017-04-01

    Employee’s occupational stress and safety performance are highly related, which has been generally recognized by the researchers. We did this research to understand the status of the stress for construction workers, and explore the influence factors of pressure source with characteristics of construction industry. Based on the results of previous studies, we designed questionnaire to collect the influence factors on occupational stressors. The study selected workers from certain construction units at the grass-roots level as sample source. According to the results of the questionnaire, we redesigned the interview outline, and did the semi-structured interviews on workers randomly selected. Finally, we developed a scale which combined the characteristics of construction projects in China. Using SPSS software for factor analysis, reliability analysis, and descriptive statistical analysis, the results show that there are six factors affecting the workers’ occupational stress, including The Work Itself, Family-Work, Career Development, Organization Style, Interpersonal Relationship and Role Management Style. The work itself is the main sources of occupational stress. The results can be used by the construction company to provide guidance for workers to control and manage occupational stress.

  19. Stress intensity factors for complete internal and external cracks in spherical shells

    International Nuclear Information System (INIS)

    Chao, Y.J.; Chen, H.

    1989-01-01

    Cracks or flows found in the nuclear structure must be fully evaluated to assure the safety of the plant. The weight function method has been widely used in the determination of stress intensity factors for cracks under stress gradient e.g. for thermal shock loading. The unique features of the weight function method is that once the weight function for a particular cracked geometry is determined the stress intensity factors at the crack tip for any loading applied to the flawed structure can be calculated by a simple integration. In this paper the stress intensity factors of the complete, part-through internal and external cracks in a spherical shell are determined. The finite element method was used to develop the weight functions for the flawed geometry. The approximate crack surface profile was used to derive the weight functions. The stress intensity factors associated with the cracks in spherical shells under internal pressure are determined by both the weight functions and the direct finite element method

  20. Further studies on stress intensity factors of semi-elliptical cracks in pressurized cylinders

    International Nuclear Information System (INIS)

    Kobayashi, A.S.; Emery, A.F.; Love, W.J.; Jain, A.

    1979-01-01

    The authors have used, in the past, the three-dimensional stress intensity magnification factor, Msub(KS), for a semi-elliptical surface crack in a flat plate with a curvature correction factor, Msub(C), to estimate the stress intensity magnification factor, Msub(K) = Msub(C) x Msub(KS), for unpressurized and pressurized inner semi-elliptical cracks and unpressurized outer semi-elliptical cracks in pressurized and thermally shocked cylinders. Recent papers by Atluri/Kathiresan, Welliot/Labbens/Pellissier-Tanon and McGowan/Raymund, however, showed that while this plate analogy with curvature correction provided reasonable estimates of the stress intensity factors at the deepest crack penetration, it underestimated the stress intensity factors at the cylindrical surface. The source of this discrepancy was traced to the curvature correction factor Msub(C), which was re-evaluated for various crack configurations and cylindrical geometries studied. Using the updated Msub(C) together with the previously derived Msub(KS), stress intensity factor magnification factor, Msub(K), was rederived for: (1) Pressurized and unpressurized inner semi-elliptical cracks of two crack aspects ratios of b/a = 0.2 and 0.98 at crack depth of b/(Rsub(o)-Rsub(i)) = 0.4, 0.6, and 0.8 in pressurized cylinders with outside-to-inside radius ratios of Rsub(o)/Rsub(i) = 3/2, 5/4, 7/6, and 10/9. (2) Unpressurized outer semi-elliptical cracks of two crack aspect ratios of b/a = 0.2 and 0.98 at crack depths of b/(Rsub(o)-Rsub(i)) = 0.4, 0.6, and 0.8 in pressurized cylinders with outside-to-inside radius ratio of Rsub(o)/Rsub(i) = 3/2, 5/4, 7/6, and 10/9. (orig.)

  1. Adaptation of children to the new environment as a stress factor in the work of teachers in nursery school

    OpenAIRE

    Vondrová, Terezie

    2018-01-01

    The topic of the bachelor thesis is children's adaptation to the nursery school education as a stress factor for the teachers. The thesis examines five areas which may cause stress to the teachers working with newly come children during the adaptation period and describes strategies teachers employ in order to cope with the stress. The expected stress factors are: children's problematic behavior, school management, colleague and parental pressure exacting fast and smooth adaptation process an...

  2. Ground Motion Uncertainty and Variability (single-station sigma): Insights from Euroseistest, Greece

    Science.gov (United States)

    Ktenidou, O. J.; Roumelioti, Z.; Abrahamson, N. A.; Cotton, F.; Pitilakis, K.

    2014-12-01

    Despite recent improvements in networks and data, the global aleatory uncertainty (sigma) in GMPEs is still large. One reason is the ergodic approach, where we combine data in space to make up for lack of data in time. By estimating the systematic site response, we can make site-specific GMPEs and use a lower, site-specific uncertainty: single-station sigma. In this study we use the EUROSEISTEST database (http://euroseisdb.civil.auth.gr), which has two distinct advantages: good existing knowledge of site conditions at all stations, and careful relocation of the recorded events. Constraining the site and source parameters as best we can, we minimise the within- and between-events components of the global, ergodic sigma. Following that, knowledge of the site response from empirical and theoretical approaches permits us to move on to single-station sigma. The variability per site is not clearly correlated to the site class. We show that in some cases knowledge of Vs30 is not sufficient, and that site-specific data are needed to capture the response, possibly due to 2D/3D effects from complex geometry. Our values of single-station sigma are low compared to the literature. This may be due to the good ray coverage we have in all directions for small, nearby records. Indeed, our single-station sigma values are similar to published single-path values, which means that they may correspond to a fully -rather than partially- non-ergodic approach. We find larger ground motion variability for short distances and small magnitudes. This may be related to the uncertainty in the depth affecting nearby records more, or to stress drop and causing trade-offs between the source and site terms for small magnitudes.

  3. Six Sigma methods applied to cryogenic coolers assembly line

    Science.gov (United States)

    Ventre, Jean-Marc; Germain-Lacour, Michel; Martin, Jean-Yves; Cauquil, Jean-Marc; Benschop, Tonny; Griot, René

    2009-05-01

    Six Sigma method have been applied to manufacturing process of a rotary Stirling cooler: RM2. Name of the project is NoVa as main goal of the Six Sigma approach is to reduce variability (No Variability). Project has been based on the DMAIC guideline following five stages: Define, Measure, Analyse, Improve, Control. Objective has been set on the rate of coolers succeeding performance at first attempt with a goal value of 95%. A team has been gathered involving people and skills acting on the RM2 manufacturing line. Measurement System Analysis (MSA) has been applied to test bench and results after R&R gage show that measurement is one of the root cause for variability in RM2 process. Two more root causes have been identified by the team after process mapping analysis: regenerator filling factor and cleaning procedure. Causes for measurement variability have been identified and eradicated as shown by new results from R&R gage. Experimental results show that regenerator filling factor impacts process variability and affects yield. Improved process haven been set after new calibration process for test bench, new filling procedure for regenerator and an additional cleaning stage have been implemented. The objective for 95% coolers succeeding performance test at first attempt has been reached and kept for a significant period. RM2 manufacturing process is now managed according to Statistical Process Control based on control charts. Improvement in process capability have enabled introduction of sample testing procedure before delivery.

  4. Fibroblast growth factor 21 and its novel association with oxidative stress

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Gómez-Sámano

    2017-04-01

    Full Text Available Fibroblast growth factor 21 (FGF21 is an endocrine-member of the FGF family. It is synthesized mainly in the liver, but it is also expressed in adipose tissue, skeletal muscle, and many other organs. It has a key role in glucose and lipid metabolism, as well as in energy balance. FGF21 concentration in plasma is increased in patients with obesity, insulin resistance, and metabolic syndrome. Recent findings suggest that such increment protects tissue from an increased oxidative stress environment. Different types of physical stress, such as strenuous exercising, lactation, diabetic nephropathy, cardiovascular disease, and critical illnesses, also increase FGF21 circulating concentration. FGF21 is now considered a stress-responsive hormone in humans. The discovery of an essential response element in the FGF21 gene, for the activating transcription factor 4 (ATF4, involved in the regulation of oxidative stress, and its relation with genes such as NRF2, TBP-2, UCP3, SOD2, ERK, and p38, places FGF21 as a key regulator of the oxidative stress cell response. Its role in chronic diseases and its involvement in the treatment and follow-up of these diseases has been recently the target of new studies. The diminished oxidative stress through FGF21 pathways observed with anti-diabetic therapy is another clue of the new insights of this hormone.

  5. Role stress in nurses: review of related factors and strategies for moving forward.

    Science.gov (United States)

    Chang, Esther M; Hancock, Karen M; Johnson, Amanda; Daly, John; Jackson, Debra

    2005-03-01

    The aim of this paper was to review the literature on factors related to role stress in nurses, and present strategies for addressing this issue based on the findings of this review while considering potential areas for development and research. Computerized databases were searched as well as hand searching of articles in order to conduct this review. This review identified multiple factors related to the experience of role stress in nurses. Role stress, in particular, work overload, has been reported as one of the main reasons for nurses leaving the workforce. This paper concludes that it is a priority to find new and innovative ways of supporting nurses in their experience of role stress. Some examples discussed in this article include use of stress education and management strategies; team-building strategies; balancing priorities; enhancing social and peer support; flexibility in work hours; protocols to deal with violence; and retention and attraction of nursing staff strategies. These strategies need to be empirically evaluated for their efficacy in reducing role stress.

  6. Psychological Stress Delays Periodontitis Healing in Rats: The Involvement of Basic Fibroblast Growth Factor

    Directory of Open Access Journals (Sweden)

    Ya-Juan Zhao

    2012-01-01

    Full Text Available Objective. To evaluate the effects of psychological stress on periodontitis healing in rats and the contribution of basic fibroblast growth factor (bFGF expression to the healing process. Methods. Ninety-six rats were randomly distributed into control group, periodontitis group, and periodontitis plus stress group. Then, the rats were sacrificed at baseline and week(s 1, 2, and 4. The periodontitis healing condition was assessed, and the expression of interleukin-1β (IL-1β, tumor necrosis factor-α (TNF-α, and bFGF were tested by immunohistochemistry. Results. The stressed rats showed reduced body weight gain, behavioral changes, and increased serum corticosterone and ACTH levels (. The surface of inflammatory infiltrate, alveolar bone loss, attachment loss, and expression of IL-1β and TNF-α in the stress group were higher than those in the periodontitis group at weeks 2 and 4 (. Rats with experimental periodontitis showed decreased bFGF expression (, and the recovery of bFGF expression in the stress group was slower than that in the periodontitis group (. Negative correlations between inflammatory cytokines and bFGF were detected. Conclusion. Psychological stress could delay periodontitis healing in rats, which may be partly mediated by downregulation of the expression of bFGF in the periodontal ligament.

  7. Stress concentration factors for an internally pressurized circular vessel containing a radial U-notch

    International Nuclear Information System (INIS)

    Carvalho, E.A. de

    2005-01-01

    This paper evaluates the stress concentration factors for an internally pressurized cylinder containing a radial U-notch along its length. This work studies the cases where the external to internal radius ratio (Ψ) is equal to 1.26, 1.52, 2.00, and 3.00 and the notch radius to internal radius ratio (Φ) is fixed and equal to 0.026. The U-notch depth varies from 0.1 to 0.6 of the wall thickness. Results are also presented for a fixed size semi-circular notch. Hoop stresses at the external wall are presented, showing regions where the stress matches the nominal one and the favourable places to install strain sensors. The finite element method is used to determine the stress concentration factors (K t ) for the above described situations and for a special case where a varying semi-circular notch is present with Ψ=3.00. This notch depth varies from 0.013 to 0.3 of the wall thickness. It is pointed out that even relatively small notches introduce large stress concentrations and disrupt the hoop stress distribution all over the cross section. Results are also compared to an example found in the literature for semi-circular notches and K t curves for both cases present the same shape

  8. Round Robin Analyses on Stress Intensity Factors of Inner Surface Cracks in Welded Stainless Steel Pipes

    Directory of Open Access Journals (Sweden)

    Chang-Gi Han

    2016-12-01

    Full Text Available Austenitic stainless steels (ASSs are widely used for nuclear pipes as they exhibit a good combination of mechanical properties and corrosion resistance. However, high tensile residual stresses may occur in ASS welds because postweld heat treatment is not generally conducted in order to avoid sensitization, which causes a stress corrosion crack. In this study, round robin analyses on stress intensity factors (SIFs were carried out to examine the appropriateness of structural integrity assessment methods for ASS pipe welds with two types of circumferential cracks. Typical stress profiles were generated from finite element analyses by considering residual stresses and normal operating conditions. Then, SIFs of cracked ASS pipes were determined by analytical equations represented in fitness-for-service assessment codes as well as reference finite element analyses. The discrepancies of estimated SIFs among round robin participants were confirmed due to different assessment procedures and relevant considerations, as well as the mistakes of participants. The effects of uncertainty factors on SIFs were deducted from sensitivity analyses and, based on the similarity and conservatism compared with detailed finite element analysis results, the R6 code, taking into account the applied internal pressure and combination of stress components, was recommended as the optimum procedure for SIF estimation.

  9. Community violence exposure and severe posttraumatic stress in suburban American youth: risk and protective factors.

    Science.gov (United States)

    Löfving-Gupta, Sandra; Lindblad, Frank; Stickley, Andrew; Schwab-Stone, Mary; Ruchkin, Vladislav

    2015-04-01

    The psychological effects of community violence exposure among inner-city youth are severe, yet little is known about its prevalence and moderators among suburban middle-class youth. This study aimed to assess the prevalence of community violence exposure among suburban American youth, to examine associated posttraumatic stress and to evaluate factors related to severe vs. less severe posttraumatic stress, such as co-existing internalizing and externalizing problems, as well as the effects of teacher support, parental warmth and support, perceived neighborhood safety and conventional involvement in this context. Data were collected from 780 suburban, predominantly Caucasian middle-class high-school adolescents in the Northeastern US during the Social and Health Assessment (SAHA) study. A substantial number of suburban youth were exposed to community violence and 24% of those victimized by community violence developed severe posttraumatic stress. Depressive symptoms were strongly associated with higher levels and perceived teacher support with lower levels of posttraumatic stress. Similar to urban youth, youth living in suburban areas in North American settings may be affected by community violence. A substantial proportion of these youth reports severe posttraumatic stress and high levels of comorbid depressive symptoms. Teacher support may have a protective effect against severe posttraumatic stress and thus needs to be further assessed as a potential factor that can be used to mitigate the detrimental effects of violence exposure.

  10. Round robin analysis on stress intensity factor of inner surface cracks in welded stainless steel pipes

    Energy Technology Data Exchange (ETDEWEB)

    Han, Chang Gi; Chang, Yoon Suk [Dept. of Nuclear Engineering, College of Engineering, Kyung Hee University, Yongin (Korea, Republic of); Kim, Jong Sung [Dept. of Mechanical Engineering, Sunchon National University, Sunchon (Korea, Republic of); Kim, Maan Won [Central Research Institute, Korea Hydro and Nuclear Power Company, Daejeon (Korea, Republic of)

    2016-12-15

    Austenitic stainless steels (ASSs) are widely used for nuclear pipes as they exhibit a good combination of mechanical properties and corrosion resistance. However, high tensile residual stresses may occur in ASS welds because postweld heat treatment is not generally conducted in order to avoid sensitization, which causes a stress corrosion crack. In this study, round robin analyses on stress intensity factors (SIFs) were carried out to examine the appropriateness of structural integrity assessment methods for ASS pipe welds with two types of circumferential cracks. Typical stress profiles were generated from finite element analyses by considering residual stresses and normal operating conditions. Then, SIFs of cracked ASS pipes were determined by analytical equations represented in fitness-for-service assessment codes as well as reference finite element analyses. The discrepancies of estimated SIFs among round robin participants were confirmed due to different assessment procedures and relevant considerations, as well as the mistakes of participants. The effects of uncertainty factors on SIFs were deducted from sensitivity analyses and, based on the similarity and conservatism compared with detailed finite element analysis results, the R6 code, taking into account the applied internal pressure and combination of stress components, was recommended as the optimum procedure for SIF estimation.

  11. The stress and stress intensity factors computation by BEM and FEM combination for nozzle junction under pressure and thermal loads

    International Nuclear Information System (INIS)

    Du, Q.; Cen, Z.; Zhu, H.

    1989-01-01

    This paper reports linear elastic fracture analysis based upon the stress intensity factor evaluation successfully applied to safety assessments of cracked structures. The nozzle junction are usually subjected to high pressure and thermal loads simultaneously. In validity of linear elastic fracture analysis, K can be decomposed into K P (caused by mechanic loads) and K τ (caused by thermal loads). Under thermal transient loading, explicit analysis (say by the FEM or BEM) of K tracing an entire history respectively for a range of crack depth may be much more time consuming. The techniques of weight function provide efficient means for transforming the problem into the stress computation of the uncracked structure and generation of influence function (for the given structure and size of crack). In this paper, a combination of BE-FEM has been used for the analysis of the cracked nozzle structure by techniques of weight function. The influence functions are obtained by coupled BE-FEM and the uncracked structure stress are computed by finite element methods

  12. Perceived stress among male medical students in Egypt and Saudi Arabia : Effect of sociodemographic factors

    International Nuclear Information System (INIS)

    Abdel-Hady El-Gilany; Mostafa Amr; Sabry Hammad

    2010-01-01

    In Arab countries, epidemiological data about psychological morbidity among medical undergraduate students are scarce. This study sought to determine whether there was a difference in perceived stress levels of male medical students at Mansoura University, Egypt, compared with male medical students at King Faisal University, Saudi Arabia.The sample consisted of 304 male medical students in Egypt and and 284 male medical students in Saudi Arabia. The self-reported questionnaire covered four categories, including 15 items, on sources of stress (stressors). The perceived stress scale and hospital anxiety and depression scale were used to measure stress, anxiety and depression.There was no significant difference between the two groups in number of stressors. However, Egyptian students were more likely to cite relationship, academic and environmental problems than Saudis. The prevalence of high stress was nearly equal in both groups. However, anxiety and depression were significantly higher among Egyptian than Saudi students. A logistic regression analysis of independent predictors of severe stress among both groups combined revealed that a satisfactory family income and university-graduated father were independent protective factors. The independent risk predictors were anxiety and number of stressors.Stress, anxiety and depression are frequent among medical students. Counseling and preventive mental health services should be an integral part of the routine clinical facilities caring for medical students (Author).

  13. Perceived stress among male medical students in Egypt and Saudi Arabia:effects of sociodemographic factors

    International Nuclear Information System (INIS)

    El-Ghilany, A.; Amr, M.; Hammad, S.

    2008-01-01

    In Arab countries, epidemiological data about psychological morbidityamong medical undergraduate students are scarce. This study sought todetermine whether there was a difference in perceived stress levels of malemedical students at Mansoura University, Egypt, compared with male medicalstudents at King Faisal University, Saudi Arabia. The sample consisted of 304male medical students in Egypt and 284 male medical students in Saudi Arabia.The self-reported questionnaire covered four categories, including 15 items,on sources of stress (stressors). The perceived stress scale and hospitalanxiety and depression scale were used to measure stress, anxiety anddepression. There was no significant difference between two groups in numberof stressors. However, Egyptian students were more likely to citerelationship, academic and environmental problems than Saudis. The prevalenceof high stress was nearly equal in both groups. However, anxiety anddepression were significantly higher among Egyptian than Saudi students. Alogistic regression analysis of independent predictors of severe stress amongboth groups combined revealed that a satisfactory family income anduniversity-graduated father were independent protective factors. Theindependent risk predictors were anxiety and number stressors. Stress,anxiety and depression are frequent among medical students. Counseling andpreventive metal heath services should be an integral part of the routinefacilities caring for medical students. (author)

  14. Acute stress in residents during emergency care: a study of personal and situational factors.

    Science.gov (United States)

    Dias, Roger Daglius; Scalabrini Neto, Augusto

    2017-05-01

    Providing care for simulated emergency patients may induce considerable acute stress in physicians. However, the acute stress provoked in a real-life emergency room (ER) is not well known. Our aim was to assess acute stress responses in residents during real emergency care and investigate the related personal and situational factors. A cross-sectional observational study was carried out at an emergency department of a tertiary teaching hospital. All second-year internal medicine residents were invited to voluntarily participate in this study. Acute stress markers were assessed at baseline (T1), before residents started their ER shift, and immediately after an emergency situation (T2), using heart rate, systolic, and diastolic blood pressure, salivary α-amylase activity, salivary interleukin-1 β, and the State-Trait Anxiety Inventory (STAI-s and STAI-t). Twenty-four residents were assessed during 40 emergency situations. All stress markers presented a statistically significant increase between T1 and T2. IL-1 β presented the highest percent increase (141.0%, p stress in residents. Resident experience, trait anxiety, and number of emergency procedures were independently associated with acute stress response.

  15. Analisis Pengendalian Kualitas Super Absorbent Polymer Dengan Menggunakan Metode Six Sigma

    Directory of Open Access Journals (Sweden)

    Rosihin Rosihin

    2017-07-01

    Full Text Available Quality control is an effort to increase customer satisfaction and minimize damage. Super Absorbent Polymer which is a product as a raw material for making baby diapers / elderly and sanitary napkins. In Super Absorbent Polymer, defects usually found in the colour contamination that there is a dark colour on the product, print labels mistakes and packaging defects. This study aims to determine the value of DPMO and sigma level, identify the efforts which is taken to reduce disability, identify the types of disability, and find the main factors causing disability. Six Sigma method is used to analyze data with define, measure, analyze, improve and control. The quantitative data obtained by direct observation of quality problems. By using the method of six sigma can be seen that the quality of the resulting product is quite good that is 3.07 sigma with a damage rate of 58,624 for a million production (DPMO. The three highest defect product causes are color contamination of 93.34%, misprint of 3.55%, and packaging damage as much as 3.11%. The main factor causing defects is the engine factor for the type of colour contamination defect,. The type of improper defects in the packaging labels and main factor for the packaging defects is the human factor.kecacatan rusaknya kemasan faktor utama ialah faktor manusia.

  16. Validating the Farsi version of the Pregnancy Worries and Stress Questionnaire (PWSQ): An exploratory factor analysis.

    Science.gov (United States)

    Navidpour, Fariba; Dolatian, Mahrokh; Shishehgar, Sara; Yaghmaei, Farideh; Majd, Hamid Alavi; Hashemi, Seyed Saeed

    2016-10-01

    Biological, environmental, inter- and intrapersonal changes during the antenatal period can result in anxiety and stress in pregnant women. It is pivotal to identify potential stressors and prevent their foetal and maternal consequences. The present study was conducted to validate and examine the factor structure of the Farsi version of the Pregnancy Worries and Stress Questionnaire (PWSQ). In 2015, 502 Iranian healthy pregnant women, referred to selected hospitals in Tehran for prenatal care at 8-39 weeks of pregnancy, were recruited through a randomized cluster sampling. The PWSQ was translated into Farsi, and its validity and reliability were examined using exploratory factor analysis by SPSS version 21. The content validity of items on the PWSQ was between 0.63-1. The content validity index for relevance, clarity and simplicity were 0.92, 0.98, and 0.98, respectively, with a mean of 0.94. The Kaiser-Meyer-Olkin measure of sampling adequacy was 0.863. Test-retest reliability showed high internal consistency (α=0.89; p<0.0001). The psychometric evaluation and exploratory factor analysis showed that the translated questionnaire is a valid and reliable tool to identify stress in Iranian pregnant women. Application of the questionnaire can facilitate the diagnosis of stress in pregnant women and assist health care providers in providing timely support and minimizing negative outcomes of stress and anxiety in pregnant women and their infants.

  17. Stress, anxiety, depression, and epilepsy: investigating the relationship between psychological factors and seizures.

    Science.gov (United States)

    Thapar, Ajay; Kerr, Michael; Harold, Gordon

    2009-01-01

    The goal of the study described here was to examine the interrelationship between psychological factors (anxiety, stress, and depression) and seizures. In this longitudinal cohort study, data on anxiety, depression, perceived stress, and seizure recency (time since last seizure) and frequency were collected at two time points using standard validated questionnaire measures. Empirically based models with psychological factors explaining change in (1) seizure recency and (2) seizure frequency scores across time were specified. We then tested how these psychological factors acted together in predicting seizure recency and frequency. Our data were used to test whether these models were valid for the study population. Latent variable structural equation modeling was used for the analysis. Four hundred thirty-three of the 558 individuals who initially consented to participate provided two waves of data for this analysis. Stress (beta=0.25, Panxiety (beta=0.30, Pdepression (beta=0.30, Pdepression that mediated the relationship of both anxiety and stress with modeled change in seizure recency (beta=0.19, PDepression mediates the relationship between stress and anxiety and change in seizure recency and seizure frequency. These findings highlight the importance of depression management in addition to seizure management in the assessment and treatment of epilepsy in an adult population.

  18. Perceived heart risk factors can predict experienced psychological stress in outpatient cardiac rehabilitation

    Directory of Open Access Journals (Sweden)

    Mozhgan Saeidi

    2018-01-01

    Full Text Available Background: The study was done to investigate the role of perceived heart risk factors (PHRFs in the prediction of psychological symptoms of cardiac rehabilitation (CR patients. Methods: In this cross-sectional study, 124 CR patients referred to Kermanshah Hospital of Imam Ali were assessed during April–July 2015. PHRFs scale and Depression, Anxiety, and Stress scale-21 used for data collection. The data were analyzed using linear multiple regression analysis. Results: The mean age of samples (69.4% male was 58.9 ± 9.7 years. The results of regression analysis evidenced that there is no significant relationship between any of the PHRFs with depression and anxiety (P > 0.05; however, biological (P = 0.018 and psychological (P = 0.019 risk factors significantly can predict stress. The model generally can explain 6.4% of the stress variance. Conclusion: PHRFs are included some significant predictors for experienced stress among the CR patients. Given that the biological and psychological risk factors are more effective in experienced stress by the patients, it is recommended that specialists pay more attention to the potential psychological outcomes of this group of patients.

  19. Ribosomal elongation factor 4 promotes cell death associated with lethal stress.

    Science.gov (United States)

    Li, Liping; Hong, Yuzhi; Luan, Gan; Mosel, Michael; Malik, Muhammad; Drlica, Karl; Zhao, Xilin

    2014-12-09

    Ribosomal elongation factor 4 (EF4) is highly conserved among bacteria, mitochondria, and chloroplasts. However, the EF4-encoding gene, lepA, is nonessential and its deficiency shows no growth or fitness defect. In purified systems, EF4 back-translocates stalled, posttranslational ribosomes for efficient protein synthesis; consequently, EF4 has a protective role during moderate stress. We were surprised to find that EF4 also has a detrimental role during severe stress: deletion of lepA increased Escherichia coli survival following treatment with several antimicrobials. EF4 contributed to stress-mediated lethality through reactive oxygen species (ROS) because (i) the protective effect of a ΔlepA mutation against lethal antimicrobials was eliminated by anaerobic growth or by agents that block hydroxyl radical accumulation and (ii) the ΔlepA mutation decreased ROS levels stimulated by antimicrobial stress. Epistasis experiments showed that EF4 functions in the same genetic pathway as the MazF toxin, a stress response factor implicated in ROS-mediated cell death. The detrimental action of EF4 required transfer-messenger RNA (tmRNA, which tags truncated proteins for degradation and is known to be inhibited by EF4) and the ClpP protease. Inhibition of a protective, tmRNA/ClpP-mediated degradative activity would allow truncated proteins to indirectly perturb the respiratory chain and thereby provide a potential link between EF4 and ROS. The connection among EF4, MazF, tmRNA, and ROS expands a pathway leading from harsh stress to bacterial self-destruction. The destructive aspect of EF4 plus the protective properties described previously make EF4 a bifunctional factor in a stress response that promotes survival or death, depending on the severity of stress. Translation elongation factor 4 (EF4) is one of the most conserved proteins in nature, but it is dispensable. Lack of strong phenotypes for its genetic knockout has made EF4 an enigma. Recent biochemical work has

  20. Factors affecting the job stress and job satisfaction of Australian nurses: implications for recruitment and retention.

    Science.gov (United States)

    Bartram, Timothy; Joiner, Therese A; Stanton, Pauline

    2004-10-01

    Against a background of nurse shortages in Australian hospitals, a significant challenge facing the healthcare sector is the recruitment and retention of nurses. The job stress and job satisfaction of nurses have been associated with recruitment and retention. The aim of this study is to consider two factors that may contribute to the job satisfaction and job stress of nurses: social support and empowerment. Using a sample of 157 registered nurses in a private hospital in Melbourne, Australia, we found that social support derived from the nurse's supervisor and work colleagues lowered job stress and at the same time increased job satisfaction. The presence of nurse empowerment, meaning, impact, competence and self-determination, also lowered job stress and increased job satisfaction. Finally, we discuss contributions of this study and implications for recruitment and retention of nurses in the health sector.

  1. Are plant endogenous factors like ethylene modulators of the early oxidative stress induced by mercury?

    Directory of Open Access Journals (Sweden)

    M Belén eMontero-Palmero

    2014-08-01

    Full Text Available The induction of oxidative stress is one of the quickest symptoms appearing in plants subjected to metal stress. A transcriptional analysis of the early responses of alfalfa (Medicago sativa seedlings to mercury (Hg; 3 µM for 3, 6 and 24 h showed that up-regulation of genes responding to ethylene were up-regulated, a phytohormone known to mediate in the cellular redox homeostasis. In this mini-review we have compared these quick responses with two other concurrent transcriptomic analysis in Barrel medic (Medicago truncatula and barley (Hordeum vulgare under Hg stress. Besides ethylene, ABA and jasmonate related genes were up-regulated, all of them are endogenous factors known to intervene in oxidative stress responses. The information obtained may target future work to understand the cellular mechanisms triggered by Hg, enabling biotechnological approaches to diminish Hg-induced phytotoxicity.

  2. Six sigma: program characteristics in eleven companies located in the metropolitan region of Porto Alegre

    Directory of Open Access Journals (Sweden)

    Jaqueline Terezinha Martins Correa Rodrigues

    2012-01-01

    Full Text Available Six Sigma combines managerial factors with statistical tools and is deployed in many enterprises today. Rio Grande do Sul is a Brazilian state that has a great industrialization, especially in the metropolitan area of Porto Alegre. Some of these industries have deployed the Six Sigma program. The aim of this paper is to present characteristics of the Six Sigma program in companies located in this region, through an exploratory study. A literature review subsidized the development of the questionnaire. Eleven companies participated of research in July and August 2008. It used statistical tools and qualitative analysis to analyze the results. Most of the companies that participated is classified as large and uses the DMAIC method to implement Six Sigma. The principal cause of program implementation was process improvement. In only one company the Six Sigma is implemented in all sectors, including administrative areas. Another result is the lack of clearly criteria for defining the career of Belts and the discrepancy of academic formation of these specialists.

  3. In situ subsoil stress-strain behaviour in relation to soil precompression stress

    DEFF Research Database (Denmark)

    Keller, T; Arvidsson, J; Schjønning, Per

    2012-01-01

    is assumed to be elastic and reversible as long as [sigma] work examined soil stress-strain behavior as measured in situ during wheeling experiments and related it to the stress-strain behavior and [sigma]pc measured on soil cores in uniaxial compression tests in the laboratory. The data......Soil compaction negatively influences many important soil functions, including crop growth. Compaction occurs when the applied stress, [sigma], overcomes the soil strength. Soil strength in relation to compaction is typically expressed by the soil precompression stress, [sigma]pc. Deformation...... analyzed were from a large number of wheeling experiments carried out in Sweden and Denmark on soils with a wide range of texture. Contradicting the concept of precompression stress, we observed residual strain, [Latin Small Letter Open E]res, at [sigma

  4. The antioxidative system of Norway spruce: Effects of different stress factors. Das antioxidative System der Fichte: Einfluss von verschiedenen Stressfaktoren

    Energy Technology Data Exchange (ETDEWEB)

    Schittenhelm, J. (Freiburg Univ., Inst. fuer Biologie 2, Abt. Botanik (Germany)); Westphal, S. (Freiburg Univ., Inst. fuer Biologie 2, Abt. Botanik (Germany)); Toder, S. (Freiburg Univ., Inst. fuer Biologie 2, Abt. Botanik (Germany)); Wagner, E. (Freiburg Univ., Inst. fuer Biologie 2, Abt. Botanik (Germany))

    1993-08-01

    The effects of different stress factors on the antioxidative system of 6-year-old Norway spruces of the same clone were examined. Flooding and permanent darkness had only minor effects. On the other hand drought, chilling, intense light, and very high ozone concentrations showed strong but distinct consequences. This indicates that the damages by these stress factors are due to different toxic oxygen species, and that the stress factors could produce synergistic damages under natural field conditions. (orig.)

  5. Associations of menopausal symptoms with job-related stress factors in nurses in Japan.

    Science.gov (United States)

    Matsuzaki, Kazuyo; Uemura, Hirokazu; Yasui, Toshiyuki

    2014-09-01

    The main objective was to ascertain the typical menopausal symptoms and job-related stress factors in Japanese nurses during the menopausal transition, and the associations of menopausal symptoms with job-related stress. A supplementary objective was to determine whether there were any differences in menopausal symptoms and job-related stress factors among nurses in managerial positions. One thousand seven hundred female registered nurses aged 45-60 years who were working in hospitals in Japan were asked to complete a self-administered survey that included Greene's Climacteric Scale and the Brief Job Stress Questionnaire. The proportions of nurses who reported feelings of tiredness, irritability and difficulty in concentration were higher than the proportions with other menopausal symptoms. The proportions of nurses reporting feeling unhappy or depressed and having crying spells were higher among nurses in managerial positions than among other nurses. Stresses related to 'quantitative overload' on the Brief Job Stress Questionnaire among nurses in managerial positions were significantly greater than among nurses not in managerial positions, while stresses related to 'physical overload', 'job control', 'skill discretion', 'workplace environment' and 'job satisfaction' among nurses not in managerial positions were significantly greater than they were among nurses in managerial positions. Psychological symptoms were significantly correlated with poor job-related interpersonal relationships. Health care practitioners should be aware that menopausal symptoms are associated with job-related stress during the menopausal transition. Information on the differences in these associations between nurses in managerial positions and other nurses is important as it will allow their health care to be managed on a more individual basis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. The SigmaR1 chaperone drives breast and colorectal cancer cell migration by tuning SK3-dependent Ca2+ homeostasis.

    Science.gov (United States)

    Gueguinou, M; Crottès, D; Chantôme, A; Rapetti-Mauss, R; Potier-Cartereau, M; Clarysse, L; Girault, A; Fourbon, Y; Jézéquel, P; Guérin-Charbonnel, C; Fromont, G; Martin, P; Pellissier, B; Schiappa, R; Chamorey, E; Mignen, O; Uguen, A; Borgese, F; Vandier, C; Soriani, O

    2017-06-22

    The remodeling of calcium homeostasis contributes to the cancer hallmarks and the molecular mechanisms involved in calcium channel regulation in tumors remain to be characterized. Here, we report that SigmaR1, a stress-activated chaperone, is required to increase calcium influx by triggering the coupling between SK3, a Ca 2+ -activated K + channel (KCNN3) and the voltage-independent calcium channel Orai1. We show that SigmaR1 physically binds SK3 in BC cells. Inhibition of SigmaR1 activity, either by molecular silencing or by the use of sigma ligand (igmesine), decreased SK3 current and Ca 2+ entry in breast cancer (BC) and colorectal cancer (CRC) cells. Interestingly, SigmaR1 inhibition diminished SK3 and/or Orai1 levels in lipid nanodomains isolated from BC cells. Analyses of tissue microarray from CRC patients showed higher SigmaR1 expression levels in cancer samples and a correlation with tumor grade. Moreover, the exploration of a cohort of 4937 BC patients indicated that high expression of SigmaR1 and Orai1 channels was significantly correlated to a lower overall survival. As the SK3/Orai1 tandem drives invasive process in CRC and bone metastasis progression in BC, our results may inaugurate innovative therapeutic approaches targeting SigmaR1 to control the remodeling of Ca 2+ homeostasis in epithelial cancers.

  7. Risk factors for stress fracture among young female cross-country runners.

    Science.gov (United States)

    Kelsey, Jennifer L; Bachrach, Laura K; Procter-Gray, Elizabeth; Nieves, Jeri; Greendale, Gail A; Sowers, Maryfran; Brown, Byron W; Matheson, Kim A; Crawford, Sybil L; Cobb, Kristin L

    2007-09-01

    To identify risk factors for stress fracture among young female distance runners. Participants were 127 competitive female distance runners, aged 18-26, who provided at least some follow-up data in a randomized trial among 150 runners of the effects of oral contraceptives on bone health. After completing a baseline questionnaire and undergoing bone densitometry, they were followed an average of 1.85 yr. Eighteen participants had at least one stress fracture during follow-up. Baseline characteristics associated (Pstress fracture occurrence were one or more previous stress fractures (rate ratio [RR] [95% confidence interval]=6.42 (1.80-22.87), lower whole-body bone mineral content (RR=2.70 [1.26-5.88] per 1-SD [293.2 g] decrease), younger chronologic age (RR=1.42 [1.05-1.92] per 1-yr decrease), lower dietary calcium intake (RR=1.11 [0.98-1.25] per 100-mg decrease), and younger age at menarche (RR=1.92 [1.15-3.23] per 1-yr decrease). Although not statistically significant, a history of irregular menstrual periods was also associated with increased risk (RR=3.41 [0.69-16.91]). Training-related factors did not affect risk. The results of this and other studies indicate that risk factors for stress fracture among young female runners include previous stress fractures, lower bone mass, and, although not statistically significant in this study, menstrual irregularity. More study is needed of the associations between stress fracture and age, calcium intake, and age at menarche. Given the importance of stress fractures to runners, identifying preventive measures is of high priority.

  8. Stress intensity magnification factors for fully circumferential cracks in valve bodies (thick cylinders)

    International Nuclear Information System (INIS)

    Toor, P.M.

    1998-01-01

    The stress intensity solutions presented herein were obtained using an energy method in conjunction with a two-dimensional finite element program in order to explicitly account for curvature effect for fully circumferential cracks. The magnification factors for a specific crack depth were calculated by successively loading the crack surface by a uniform, linear, quadratic, and a cubic loading distribution. The magnification factors can be used to calculate the stress intensity factors by superposition method. The functions for each load condition in terms of radius to thickness ratio (R/t) and a fractional distance in terms of crack depth to thickness ratio (a/t) were developed. The validity of these functions is R/t = 1.5 to 10.0 and for 0.0125 ≤ a/t ≤ 0.8125. The functions agree to within 1% of the finite elements solutions for most magnification factors

  9. Six sigma and lean production adoption in a manufacturing company

    Directory of Open Access Journals (Sweden)

    Alisson Christian Scheller

    2014-11-01

    Full Text Available The connection among Lean Production with Six Sigma originated the Lean Six Sigma methodology, focused on processes variation and waste reduction. This methodology was developed on different ways in the companies and there is no consensus over its structure and its implementation. In this context, this paper aims to identify and analyze the main characteristics on the adoption and integration of Lean Six Sigma methodology through a case study conducted in a manufacturing company that adopts lean production and six sigma. The results show two important aspects of the Lean Six Sigma methodology. One of them is the adoption of the value stream mapping as a central tool on Lean Six Sigma. The other is the use of DMAIC for improvements actions. The study indicates that despite the difficulties on Lean Six Sigma implementation, the methodology offers benefits to the company that adopts it in the suitable way.

  10. Burnout and stress factors in special education teachers who provide extra professional support

    OpenAIRE

    Pogačnik Janežič, Olga

    2015-01-01

    In the thesis, we discuss the work of special education teachers, who provide extra professional support to children in need. Limitations and weaknesses of their work are also reviewed. Many factors, including changes in the general system of education, parents’ high expectations, unpleasant classroom circumstances, high amount of work tasks and employment uncertainty are just a few of the factors that lead to higher amounts of work-related stress and burnout syndrome. The purpose of the thes...

  11. Gravity-induced stress as a factor reducing decay of sandstone monuments in Petra, Jordan

    Czech Academy of Sciences Publication Activity Database

    Řihošek, J.; Bruthans, J.; Mašín, D.; Filippi, Michal; Carling, G. T.; Schweigstillová, Jana

    2016-01-01

    Roč. 19, 1 May (2016), s. 415-425 ISSN 1296-2074 R&D Projects: GA ČR GA13-28040S Institutional support: RVO:67985831 ; RVO:67985891 Keywords : Decay * Petra * sandstone monument * stability * stress Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.838, year: 2016

  12. Secondary Traumatic Stress in Public School Teachers: Contributing and Mitigating Factors

    Science.gov (United States)

    Caringi, James C.; Stanick, Cameo; Trautman, Ashley; Crosby, Lindsay; Devlin, Mary; Adams, Stephanie

    2015-01-01

    Although research has examined secondary traumatic stress (STS) among mental health workers, child welfare workers, and other human service professionals, such examination among public school teachers has only recently begun. This study represents the first investigation to examine the factors that influence STS levels in public School teachers.…

  13. The Factors Predicting Stress, Anxiety and Depression in the Parents of Children with Autism

    Science.gov (United States)

    Falk, Nicholas Henry; Norris, Kimberley; Quinn, Michael G.

    2014-01-01

    The factors predicting stress, anxiety and depression in the parents of children with autism remain poorly understood. In this study, a cohort of 250 mothers and 229 fathers of one or more children with autism completed a questionnaire assessing reported parental mental health problems, locus of control, social support, perceived parent-child…

  14. Posttraumatic Stress Disorder's Frequency and Intensity Ratings Are Associated with Factor Structure Differences in Military Veterans

    Science.gov (United States)

    Elhai, Jon D.; Palmieri, Patrick A.; Biehn, Tracey L.; Frueh, B. Christopher; Magruder, Kathryn M.

    2010-01-01

    We examined possible differences in the factor structure of posttraumatic stress disorder (PTSD) on the basis of whether frequency or intensity symptom response formats were used to assess PTSD. Participants included 669 veterans recruited from an epidemiological study of four Veterans Affairs Medical Centers' primary care clinics in the…

  15. Exposure to Political Conflict and Violence and Posttraumatic Stress in Middle East Youth: Protective Factors

    Science.gov (United States)

    Dubow, Eric F.; Huesmann, L. Rowell; Boxer, Paul; Landau, Simha; Dvir, Shira; Shikaki, Khalil; Ginges, Jeremy

    2012-01-01

    We examine the role of family- and individual-level protective factors in the relation between exposure to ethnic-political conflict and violence and posttraumatic stress among Israeli and Palestinian youth. Specifically, we examine whether parental mental health (lack of depression), positive parenting, children's self-esteem, and academic…

  16. Review and synthesis of stress intensity factor solutions applicable to cracks in bolts

    International Nuclear Information System (INIS)

    James, L.A.; Mills, W.J.

    1988-01-01

    The available literature for stress intensity factor solutions for cracks in round bars, both threaded and unthreaded, subjected to either tension or bending, is reviewed. The results are synthesized into a form that is appropriate for the analysis of bolts and studs. (author)

  17. Evaluation of stress intensity factor for craks in surface of tubes with internal pressure

    International Nuclear Information System (INIS)

    Cesari, F.; Hellen, T.K.

    1977-01-01

    In this report the authors have examined the different methods for calculation of the stress intensity factor in tubes subject at internal pressure with surface cracks. The analysis includes cracks in 2-D axialsymmetric and 3-D. Moreover the authors have clarified the difference between the ASME Sec.11 and the procedure more rigorous

  18. Measurement and interpretation of threshold stress intensity factors for steels in high-pressure hydrogen gas.

    Energy Technology Data Exchange (ETDEWEB)

    Dadfarnia, Mohsen (University of Illinois at Urbana-Champaign, Urbana, IL); Nibur, Kevin A.; San Marchi, Christopher W.; Sofronis, Petros (University of Illinois at Urbana-Champaign, Urbana, IL); Somerday, Brian P.; Foulk, James W., III; Hayden, Gary A. (CP Industries, McKeesport, PA)

    2010-07-01

    Threshold stress intensity factors were measured in high-pressure hydrogen gas for a variety of low alloy ferritic steels using both constant crack opening displacement and rising crack opening displacement procedures. The sustained load cracking procedures are generally consistent with those in ASME Article KD-10 of Section VIII Division 3 of the Boiler and Pressure Vessel Code, which was recently published to guide design of high-pressure hydrogen vessels. Three definitions of threshold were established for the two test methods: K{sub THi}* is the maximum applied stress intensity factor for which no crack extension was observed under constant displacement; K{sub THa} is the stress intensity factor at the arrest position for a crack that extended under constant displacement; and K{sub JH} is the stress intensity factor at the onset of crack extension under rising displacement. The apparent crack initiation threshold under constant displacement, K{sub THi}*, and the crack arrest threshold, K{sub THa}, were both found to be non-conservative due to the hydrogen exposure and crack-tip deformation histories associated with typical procedures for sustained-load cracking tests under constant displacement. In contrast, K{sub JH}, which is measured under concurrent rising displacement and hydrogen gas exposure, provides a more conservative hydrogen-assisted fracture threshold that is relevant to structural components in which sub-critical crack extension is driven by internal hydrogen gas pressure.

  19. Calculations of the stress intensity factor on a specimen for a four-point bend

    International Nuclear Information System (INIS)

    Lauerova, D.

    1995-02-01

    The stress intensity factor K I was calculated in dependence on the crack length in a sample for a (non-standard) four-point bend assuming elastic properties of the material. It is shown that the SYSTUS code gives the best results when calculating the K I value from the J-integral. 4 tabs., 12 figs., 4 refs

  20. Modified Weibull theory and stress-concentration factors of polycrystalline graphite

    International Nuclear Information System (INIS)

    Ho, F.H.

    1980-12-01

    Stress concentration factors (SCF) due to geometric discontinuities in graphite specimens are observed to be much less than the theoretical SCF in an elastic material. In fact, the experimental SCF is always less than two and sometimes even less than one. A four parameter Weibull theory which recognizes the grain size effect is found to give an adequate explanation of the above observed discrepancies

  1. The Latent Factor Structure of Acute Stress Disorder following Bank Robbery

    DEFF Research Database (Denmark)

    Hansen, M.; Lasgaard, M.; Elklit, A.

    2013-01-01

    of the latent structure of ASD were specified and estimated. METHOD: The analyses were based on a national study of bank robbery victims (N = 450) using the acute stress disorder scale. RESULTS: The results of the confirmatory factor analyses showed that the DSM-IV model provided the best fit to the data. Thus...

  2. Women in Higher Education: Exploring Stressful Workplace Factors and Coping Strategies

    Science.gov (United States)

    Kersh, Renique

    2018-01-01

    For women administrators in higher education, workplace factors like managing multiple roles; work bleeding into personal life; issues with leadership; discrimination and marginalization; and role insufficiency (i.e., ambiguity in work roles and reduced sense of control) contribute to increased workplace stress. Individual coping responses are…

  3. Phylogenetic characterization of Clonorchis sinensis proteins homologous to the sigma-class glutathione transferase and their differential expression profiles.

    Science.gov (United States)

    Bae, Young-An; Kim, Jeong-Geun; Kong, Yoon

    2016-01-01

    Glutathione transferase (GST) is one of the major antioxidant proteins with diverse supplemental activities including peroxidase, isomerase, and thiol transferase. GSTs are classified into multiple classes on the basis of their primary structures and substrate/inhibitor specificity. However, the evolutionary routes and physiological environments specific to each of the closely related bioactive enzymes remain elusive. The sigma-like GSTs exhibit amino acid conservation patterns similar to the prostaglandin D synthases (PGDSs). In this study, we analyzed the phylogenetic position of the GSTs of the biocarcinogenic liver fluke, Clonorchis sinensis. We also observed induction profile of the GSTs in association with the parasite's maturation and in response to exogenous oxidative stresses, with special attention to sigma-class GSTs and PGDSs. The C. sinensis genome encoded 12 GST protein species, which were separately assigned to cytosolic (two omega-, one zeta-, two mu-, and five sigma-class), mitochondrial (one kappa-class), and microsomal (one membrane-associated proteins in eicosanoid and glutathione metabolism-like protein) GST families. Multiple sigma GST (or PGDS) orthologs were also detected in Opisthorchis viverrini. Other trematode species possessed only a single sigma-like GST gene. A phylogenetic analysis demonstrated that one of the sigma GST lineages duplicated in the common ancestor of trematodes were specifically expanded in the opisthorchiids, but deleted in other trematodes. The induction profiles of these sigma GST genes along with the development and aging of C. sinensis, and against various exogenous chemical stimuli strongly suggest that the paralogous sigma GST genes might be undergone specialized evolution to cope with the diverse hostile biochemical environments within the mammalian hepatobiliary ductal system. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. DEPRESSION, ANXIETY, STRESS, AND THEIR ASSOCIATED FACTORS AMONG CORPS MEMBERS SERVING IN KEBBI STATE.

    Science.gov (United States)

    Balami, Ahmed D

    2015-01-01

    Depression, anxiety and stress, are not only health problems by themselves, but also associated with other negative health consequences. The national youth service is usually characterized by a number of new challenges and experiences which may require life style adjustments by the corps member. However, no previous study on psychological factors has been conducted among corps members. This study was conducted to determine the prevalence of depression, anxiety and, stress and their associated factors among corps members serving in Kebbi state. A cross-sectional study was conducted among 264 corps members from four local government areas of the state. Selection of the local government areas and the individual participants was by simple random sampling. Data was collected from May to June 2014 using a self-administered questionnaire. Data analysis used chi-square test to identify the relationship between categorical variables and multivariate logistic regression to identify the independent factors for depression, anxiety and stress each. The response rate was 97%. Most of the respondents were males (63.6%), single (85.5%), and above 20 years of age (71.6%). The overall prevalences of depression, anxiety and stress among the respondents were 36.4%, 54.5% and 18.2% respectively. The independent factors for depression were; being from the North central (OR = 5.99; 95% CI: 2.194-16.354) or South-south; and the perception of earning enough income (OR = 2.987; 95% CI: 1.062-8.400). For anxiety, male gender (OR = 0.411; 95% CI: 0.169-0.999); and being from the North central were significant risk factors (OR = 3.731; 95% CI: 1.450-9.599). Being above 26 years of age was an independent risk factor for stress (OR = 0.083; 95% CI: 0.018-0.381). Also, those who had ever schooled outside their towns of residence were less likely to be stressed compared to those who had never (OR = 0.30; 95% CI: 0.110-0.855). All other factors did not show any significant association with any of

  5. Enterprise Engineering Method supporting Six Sigma Approach

    OpenAIRE

    Jochem, Roland

    2007-01-01

    Enterprise Modeling (EM) is currently in operation either as a technique to represent and understand the structure and behavior of the enterprise, or as a technique to analyze business processes, and in many cases as support technique for business process reengineering. However, EM architectures and methodes for Enterprise Engineering can also used to support new management techniques like SIX SIGMA, because these new techniques need a clear, transparent and integrated definition and descript...

  6. Generalized Mathai-Quillen Topological Sigma Models

    OpenAIRE

    Llatas, Pablo M.

    1995-01-01

    A simple field theoretical approach to Mathai-Quillen topological field theories of maps $X: M_I \\to M_T$ from an internal space to a target space is presented. As an example of applications of our formalism we compute by applying our formulas the action and Q-variations of the fields of two well known topological systems: Topological Quantum Mechanics and type-A topological Sigma Model.

  7. TQM and six sigma in accounting literature

    OpenAIRE

    Vieira, João Manuel Franco Coelho Gouveia

    2014-01-01

    This study is based on the investigation of the relation between management accounting, Total Quality Management and six sigma, in articles published in 5 of the most renowned accounting journals: Management Accounting Review; European Accounting Review; Accounting, Auditing and Accountability; Critical Perspectives on Accounting; and Accounting Organizations and Society. Despite the vast existent literature related to both management accounting and quality management, this investigation c...

  8. Examination stress at unified state examination: student destabilization or success factor?

    Directory of Open Access Journals (Sweden)

    Svetlana N. Kostromina

    2017-01-01

    Full Text Available The aim of the research is to clear up the influence of examination stress on the results of completing examination papers by students in the situation of trial General and Unified State Examinations, imitating the real-life environment of unified state certification of schoolchildren. The tasks of the research included determining the dynamics of psychophysiological stress indices at different examination stages, and evaluating additional factors (the subject in which the examination is held, the strategy of solving the variant, success of solving the task etc., influencing the quantity and quality of stress reactions at the examination.The novelty of the research is in the attempt to overcome the problem of confusing the notions of examination stress and examination anxiety, caused by metering the students’ state either before or after the examination. The technology of online monitoring the students’ psychophysiological state is used in the work, which makes it possible to eliminate a number of restrictions occurring during subjective evaluation of the state by the students themselves. Telemetric cardiorhythmography was chosen as the basic method. The method is based on a three-component model of extreme states with consequent domination of one of the three stress-reactive systems. A cardiointervalogramm was being registered in the research process in the online mode and underwent spectral analysis. The following indices of heart rate variability were recorded in order to determine stress reactions: the total power of the spectrum (TP, the spectrum power in low-frequency (LF and high-frequency (HF regions, and a vegetative balance index (relation of the spectrum powers in low-frequency and high-frequency regions (LF/HF. When the total power of the heart rate fell and, at the same time, the vegetative balance index rose, a conclusion was made of there being a stress reaction. Twenty-five students of an illustrious school were examined

  9. Combating the Military’s Escalating Pharmacy Costs: A Lean Six Sigma Approach

    Science.gov (United States)

    2008-12-01

    without illustrating anything that can essentially go wrong. Not surprisingly, not everyone shares the belief that Lean Six Sigma is a cure all for cost...or absenteeism ; however, these factors are discussed in the conclusion found in Chapter VIII. The resources are also only available during

  10. Understanding delta-sigma data converters

    CERN Document Server

    Pavan, Shanti; Temes, Gabor C

    2017-01-01

    This new edition introduces novel analysis and design techniques for delta-sigma (ΔΣ) converters in physical and conceptual terms, and includes new chapters that explore developments in the field over the last decade. This book explains the principles and operation of delta-sigma analog-to-digital converters (ADCs) in physical and conceptual terms in accordance with the most recent developments in the field. The interest of ΔΣ converter designers has shifted significantly over the past decade, due to many new applications for data converters at the far ends of the frequency spectrum. Continuous-time delta-sigma A/D converters with GHz clocks, of both lowpass and bandpass types, are required for wireless applications. At the other extreme, multiplexed ADCs with very narrow (sometimes 10 Hz wide) signal bandwidths, but very high accuracy are needed in the interfaces of biomedical and environmental sensors. To reflect the changing eeds of designers, the second edition includes significant new material on bo...

  11. [Symptoms of Depression, Anxiety and Stress Among Dental Students: Prevalence and Related Factors].

    Science.gov (United States)

    Arrieta Vergara, Katherine; Cárdenas, Shyrley Díaz; Martínez, Farith González

    2013-06-01

    To estimate the relationship between depressive symptoms, anxiety and stress and socio-demographic, academic and social factors among dental students. A cross-sectional study was carried out on dental students from a university in Cartagena, selected by simple random sampling. Students answered a self-report anonymous questionnaire of 20 questions that included demographic characteristics, depression, anxiety and stress symptoms (DASS scale 21), family function (APGAR family) and other factors associated with the academic, economic and social context. Data were analyzed computing odds ratios by binomial logistic regression. The prevalence of symptoms of anxiety, depression and stress were 37.4%, 56.6% and 45.4%, respectively. Factors associated with depressive symptoms were lack of support from friends (OR=6.2; 95%CI, 2.6-14.5), family dysfunction (OR=3.6; 95%CI, 1.9-6.6) and economic hardship (OR=2.2; 95%CI, 1.2-3.9). The anxiety symptoms were associated with family dysfunction (OR=3.1; 95%CI, 1.8-5.3) and lack of support from friends (OR=2.1; 95%CI, 1.1-5.8). Also for symptoms of stress factors family dysfunction (OR=2.3; 95%CI, 1.4-4.1), income (OR=2.4; 95%CI, 1.2-4.9) and time to rest (OR=2.3; 95%CI, 1.4-4.0). Dental students report a high prevalence of symptoms of anxiety, depression and stress. Associated factors are economic resources, family function, lack of time for rest, and social support. Copyright © 2013 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  12. Role of Stress-Related Brain-Derived Neurotrophic Factor (BDNF) in the Rat Submandibular Gland

    International Nuclear Information System (INIS)

    Tsukinoki, Keiichi; Saruta, Juri

    2012-01-01

    The nerve growth factor (NGF) family comprises NGF, brain-derived neurotrophic factor (BDNF) and neurotrophins (NTs)-3, -4/5, -6 and -7, all of which are collectively referred to as neurotrophins. However, the expression of neurotrophins other than NGF in the salivary gland has not been described in detail. Through interaction with the TrkB receptor, BDNF plays an important role in long-term potentiation. We found that BDNF expression increased within submandibular gland tissue in response to stress, suggesting that the salivary glands are sensitive to stress. In addition, stress caused increases in plasma BDNF derived from the submandibular gland and in TrkB receptor mRNA in the adrenal medulla. Plasma BDNF might activate TrkB receptors in the adrenal medulla during acute stress. The salivary glands are likely to influence not only oral health, but also systemic organs. This review addressed the relationship between hormone-like effects and stress-related BDNF expression in the rat submandibular gland

  13. Engineering tolerance to industrially relevant stress factors in yeast cell factories

    Science.gov (United States)

    Deparis, Quinten; Claes, Arne; Foulquié-Moreno, Maria R.

    2017-01-01

    Abstract The main focus in development of yeast cell factories has generally been on establishing optimal activity of heterologous pathways and further metabolic engineering of the host strain to maximize product yield and titer. Adequate stress tolerance of the host strain has turned out to be another major challenge for obtaining economically viable performance in industrial production. Although general robustness is a universal requirement for industrial microorganisms, production of novel compounds using artificial metabolic pathways presents additional challenges. Many of the bio-based compounds desirable for production by cell factories are highly toxic to the host cells in the titers required for economic viability. Artificial metabolic pathways also turn out to be much more sensitive to stress factors than endogenous pathways, likely because regulation of the latter has been optimized in evolution in myriads of environmental conditions. We discuss different environmental and metabolic stress factors with high relevance for industrial utilization of yeast cell factories and the experimental approaches used to engineer higher stress tolerance. Improving stress tolerance in a predictable manner in yeast cell factories should facilitate their widespread utilization in the bio-based economy and extend the range of products successfully produced in large scale in a sustainable and economically profitable way. PMID:28586408

  14. Engineering tolerance to industrially relevant stress factors in yeast cell factories.

    Science.gov (United States)

    Deparis, Quinten; Claes, Arne; Foulquié-Moreno, Maria R; Thevelein, Johan M

    2017-06-01

    The main focus in development of yeast cell factories has generally been on establishing optimal activity of heterologous pathways and further metabolic engineering of the host strain to maximize product yield and titer. Adequate stress tolerance of the host strain has turned out to be another major challenge for obtaining economically viable performance in industrial production. Although general robustness is a universal requirement for industrial microorganisms, production of novel compounds using artificial metabolic pathways presents additional challenges. Many of the bio-based compounds desirable for production by cell factories are highly toxic to the host cells in the titers required for economic viability. Artificial metabolic pathways also turn out to be much more sensitive to stress factors than endogenous pathways, likely because regulation of the latter has been optimized in evolution in myriads of environmental conditions. We discuss different environmental and metabolic stress factors with high relevance for industrial utilization of yeast cell factories and the experimental approaches used to engineer higher stress tolerance. Improving stress tolerance in a predictable manner in yeast cell factories should facilitate their widespread utilization in the bio-based economy and extend the range of products successfully produced in large scale in a sustainable and economically profitable way. © FEMS 2017.

  15. [Effects of occupational stress on serum tumor necrosis factor-α and interleukins].

    Science.gov (United States)

    Zhou, Wen-Hui; Yu, Shan-Fa; Jiang, Kai-You

    2010-12-01

    To explore the effect of occupational stress on serum tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-2 and IL-4. A cross-sectional epidemiological study was conducted in 200 workers from the refrigerator assembly line in Henan province in China. Psychosocial work conditions were measured by using the job demand-control model, the effort-reward imbalance model questionnaires and occupational stress measurement scale. Serum TNF-α, IL-1β, IL-2, and IL-4 concentrations were measured by radioimmunoassay or immunoradiometric assay method respectively. Serum TNF-α concentration was statistically significantly different between workers with higher affective balance level and control groups [(1.947 ± 0.173) and (2.029 ± 0.240) fmol/ml] (P life stress level and control groups [(1.759 ± 0.361) and (1.606 ± 0.381) ng/ml] (P life stress and role ambiguity were the predictors of serum IL-2 (R(2) was 0.040, 0.078 and 0.104, respectively). Reward was the predictor of serum IL-4 (R(2) = 0.030). Unhealthy psychological stress factor might be induce a marked increase in the concentrations of serum TNF-α, IL-1β, IL-2, as well as IL-4.

  16. Burnout and stress amongst interns in Irish hospitals: contributing factors and potential solutions.

    Science.gov (United States)

    Hannan, E; Breslin, N; Doherty, E; McGreal, M; Moneley, D; Offiah, G

    2018-05-01

    The transition from medical school to internship can be daunting for newly qualified doctors. High rates of stress and burnout have been reported, with negative impacts on patient care and physician wellbeing. We surveyed interns in our hospital group to evaluate rates of stress and burnout, as well as identify the causative factors and propose potential solutions to these. A hundred and one interns working in four different hospitals over a 2-year period were invited to participate in an anonymous survey. The survey collected basic demographic details and surveyed aspects of mental health using the burnout scale, Maslach Burnout Inventory (MBI) and the stress scale and 12-item General Health Questionnaire (GHQ-12). Interns were also asked to rate a variety of workplace factors on a Likert scale based on the degree of stress caused. Finally, they were surveyed on their awareness of support services available to them. Our results showed that 37% of interns met the criteria for psychological distress, high levels of emotional exhaustion, high depersonalisation and a low sense of personal accomplishment were reported in 55.4, 51.5 and 41.6%, respectively. Inadequate preparation for practice, financial worries, poor role definition and sleep deprivation were reported as significant stressors. Most were unaware of available support services and expressed interest in leaving Ireland after internship. Burnout and stress are significant problems amongst doctors in Irish hospitals. Ensuring better preparation for clinical practice and awareness of support services is vital to tackle this issue.

  17. Improving Quality of Seal Leak Test Product using Six Sigma

    Science.gov (United States)

    Luthfi Malik, Abdullah; Akbar, Muhammad; Irianto, Dradjad

    2016-02-01

    Seal leak test part is a polyurethane material-based product. Based on past data, defect level of this product was 8%, higher than the target of 5%. Quality improvement effort was done using six sigma method that included phases of define, measure, analyse, improve, and control. In the design phase, a Delphi method was used to identify factors that were critical to quality. In the measure phase, stability and process capability was measured. Fault tree analysis (FTA) and failure mode and effect analysis (FMEA) were used in the next phase to analize the root cause and to determine the priority issues. Improve phase was done by compiling, selecting, and designing alternative repair. Some improvement efforts were identified, i.e. (i) making a checklist for maintenance schedules, (ii) making written reminder form, (iii) modifying the SOP more detail, and (iv) performing a major service to the vacuum machine. To ensure the continuity of improvement efforts, some control activities were executed, i.e. (i) controlling, monitoring, documenting, and setting target frequently, (ii) implementing reward and punishment system, (iii) adding cleaning tool, and (iv) building six sigma organizational structure.

  18. Improving Quality of Seal Leak Test Product using Six Sigma

    International Nuclear Information System (INIS)

    Malik, Abdullah Luthfi; Akbar, Muhammad; Irianto, Dradjad

    2016-01-01

    Seal leak test part is a polyurethane material-based product. Based on past data, defect level of this product was 8%, higher than the target of 5%. Quality improvement effort was done using six sigma method that included phases of define, measure, analyse, improve, and control. In the design phase, a Delphi method was used to identify factors that were critical to quality. In the measure phase, stability and process capability was measured. Fault tree analysis (FTA) and failure mode and effect analysis (FMEA) were used in the next phase to analize the root cause and to determine the priority issues. Improve phase was done by compiling, selecting, and designing alternative repair. Some improvement efforts were identified, i.e. (i) making a checklist for maintenance schedules, (ii) making written reminder form, (iii) modifying the SOP more detail, and (iv) performing a major service to the vacuum machine. To ensure the continuity of improvement efforts, some control activities were executed, i.e. (i) controlling, monitoring, documenting, and setting target frequently, (ii) implementing reward and punishment system, (iii) adding cleaning tool, and (iv) building six sigma organizational structure. (paper)

  19. Improving Quality of Shoe Soles Product using Six Sigma

    Science.gov (United States)

    Jesslyn Wijaya, Athalia; Trusaji, Wildan; Akbar, Muhammad; Ma’ruf, Anas; Irianto, Dradjad

    2018-03-01

    A manufacture in Bandung produce kind of rubber-based product i.e. trim, rice rollers, shoe soles, etc. After penetrating the shoe soles market, the manufacture has met customer with tight quality control. Based on the past data, defect level of this product was 18.08% that caused the manufacture’s loss of time and money. Quality improvement effort was done using six sigma method that included phases of define, measure, analyse, improve, and control (DMAIC). In the design phase, the object’s problem and definition were defined. Delphi method was also used in this phase to identify critical factors. In the measure phase, the existing process stability and sigma quality level were measured. Fishbone diagram and failure mode and effect analysis (FMEA) were used in the next phase to analyse the root cause and determine the priority issues. Improve phase was done by designing alternative improvement strategy using 5W1H method. Some improvement efforts were identified, i.e. (i) modifying design of the hanging rack, (ii) create pantone colour book and check sheet, (iii) provide pedestrian line at compound department, (iv) buying stop watch, and (v) modifying shoe soles dies. Some control strategies for continuous improvement were proposed such as SOP or reward and punishment system.

  20. Analysis of the stress-inducible transcription factor SsNAC23 in sugarcane plants

    Directory of Open Access Journals (Sweden)

    Renata Fava Ditt

    2011-08-01

    Full Text Available Stresses such as cold and drought can impair plant yield and induce a highly complex array of responses. Sugarcane (Saccharum spp. is cultivated in tropical and subtropical areas and is considered a cold-sensitive plant. We previously showed that cold stress induces the expression of several genes in in vitro sugarcane plantlets. Here we characterize one of those genes, SsNAC23, a member of the NAC family of plant-specific transcription factors, which are induced by low temperature and other stresses in several plant species. The expression of SsNAC23 was induced in sugarcane plants exposed to low temperatures (4ºC. With the aim of further understanding the regulatory network in response to stress, we used the yeast two-hybrid system to identify sugarcane proteins that interact with SsNAC23. Using SsNAC23 as bait, we screened a cDNA expression library of sugarcane plants submitted to 4ºC for 48 h. Several interacting partners were identified, including stress-related proteins, increasing our knowledge on how sugarcane plants respond to cold stress. One of these interacting partners, a thioredoxin h1, offers insights into the regulation of SsNAC23 activity.

  1. Impact of demographic factors on usage of stress coping strategies chosen by elderly people

    Directory of Open Access Journals (Sweden)

    Dagmara Lembas

    2017-03-01

    Full Text Available Background. Old age is a particular time in which people experience plenty of changes – both progressive and regressive. Their social and economic position is changing, and human beings are confronted with a lot of difficult situations, such as the death of a spouse, illness, retirement – which particularly require them to apply a proper strategy of coping with stress. Objectives. The aim of this study was to analyze the relationship between the demographic factors and strategies of coping with stress used by elderly people. Material and methods . The study was carried out on a group of 296 residents of Szczecin who are over 60 years old. It was conducted by means of a diagnostic survey with the use of the Inventory to Measure Coping Strategies with Stress – Mini-COPE, as well as an original questionnaire form. The statistical analysis was conducted by means of SPSS Statistics 21.0 (p ≤ 0.05. Results . The results have proven the existence of a relationship between the strategies of coping with stress used by individuals over 60 and factors such as gender, level of education, economic status and financial situation. Conclusions . When coping with stress, men and women apply different strategies. In case of individuals over 60, the higher level of education and financial status they declare, the more eager they are to use active strategies of coping with stress. Seniors with a lower level of education and lower economic status have more trouble adapting to difficult situations. They have problems with taking the initiative and actively dealing with stressful events. They also more often use psychoactive substances as part of their coping mechanism.

  2. Stress

    Science.gov (United States)

    ... taking care of an aging parent. With mental stress, the body pumps out hormones to no avail. Neither fighting ... with type 1 diabetes. This difference makes sense. Stress blocks the body from releasing insulin in people with type 2 ...

  3. Thermal stress intensity factor for an axial crack in a clad cylinder

    International Nuclear Information System (INIS)

    Kuo, An Yu; Deardorf, A.F.; Riccardella, P.C.

    1993-01-01

    Many clad pressure vessels have been found to have cracks running through the inside surface cladding and into the base material. Although Young's moduli and Poisson's ratios of the clad and base materials are about the same for most of the industrial applications, coefficients of thermal expansion of the two dissimilar materials, clad and base materials, are usually quite different. For example, low alloy ferritic steel is a common base material for reactor pressure vessels (RPV) and the vessels are usually clad with austenitic stainless steel. Young's moduli for the low alloy steel and stainless steel at 350 F are 29,000 ksi and 28,000 ksi, respectively, while their coefficients of thermal expansion are 7.47x10 -6 in/in and 9.50x10 -6 in/in-degree F, respectively. The mismatch in coefficients of thermal expansion will cause high residual thermal stress even when the entire vessel is at a uniform temperature. This residual stress is one of the primary reasons why so many cracks have been found in the cladded components. In performing reactor pressure vessel integrity evaluation, such as computing probability of brittle fracture of the RPV, it is necessary to calculate stress intensity factors for cracks, which initiate from the clad material and run into the base metal. This paper presents a convenient method of calculating stress intensity factor for an axial crack emanating from the inside surface of a cladded cylinder under thermal loading. A J-integral like line integral was derived and used to calculate the stress intensity factors from finite element stress solutions of the problem

  4. Perceived stress latent factors and the burnout subtypes: a structural model in dental students.

    Science.gov (United States)

    Montero-Marín, Jesús; Piva Demarzo, Marcelo Marcos; Stapinski, Lexine; Gili, Margarita; García-Campayo, Javier

    2014-01-01

    Students of health-professions suffer high levels of stress and burnout. The aim of the present study was to evaluate the relationship between perceived stress latent factors ('tenseness' and 'frustration') and the features ('overload', 'lack of development' and 'neglect') of the three burnout subtypes ('frenetic', 'under-challenged' and 'worn-out', respectively), in a sample of Spanish dental students. The study employed a cross-sectional design. A sample of Spanish dental students (n = 314) completed the 'Perceived Stress Questionnaire' and the 'Burnout Clinical Subtype Questionnaire Student Survey'. The associations among variables were observed by means of structural equation modelling using the unweighted least squares method from polychoric correlations. Strong associations among perceived stress factors and the burnout characteristics were observed, although a distinct pattern of relations was observed for each burnout subtype. The 'overload' was moderately and positively associated with both 'tenseness' (0.45), and 'frustration' (0.38) dimensions of perceived stress; the 'lack of development' was positively associated with the 'frustration' dimension (0.72), but negatively associated with 'tenseness' (-0.69); the 'neglect' showed a weaker positive associated with 'frustration' (0.41), and a small negative association with 'tenseness' (-0.20). The model was a very good fit to the data (GFI  =  0.96; RSMR  =  0.07; AGFI = 0.96; NFI = 0.95; RFI = 0.95). The stress factors of 'frustration' and 'tenseness' seems to be related in a distinct way to the burnout subtypes in Spanish dental students. This finding suggests that intervention programs specifically tailored to these subtypes may be a promising future direction.

  5. Perceived stress latent factors and the burnout subtypes: a structural model in dental students.

    Directory of Open Access Journals (Sweden)

    Jesús Montero-Marín

    Full Text Available Students of health-professions suffer high levels of stress and burnout. The aim of the present study was to evaluate the relationship between perceived stress latent factors ('tenseness' and 'frustration' and the features ('overload', 'lack of development' and 'neglect' of the three burnout subtypes ('frenetic', 'under-challenged' and 'worn-out', respectively, in a sample of Spanish dental students.The study employed a cross-sectional design. A sample of Spanish dental students (n = 314 completed the 'Perceived Stress Questionnaire' and the 'Burnout Clinical Subtype Questionnaire Student Survey'. The associations among variables were observed by means of structural equation modelling using the unweighted least squares method from polychoric correlations.Strong associations among perceived stress factors and the burnout characteristics were observed, although a distinct pattern of relations was observed for each burnout subtype. The 'overload' was moderately and positively associated with both 'tenseness' (0.45, and 'frustration' (0.38 dimensions of perceived stress; the 'lack of development' was positively associated with the 'frustration' dimension (0.72, but negatively associated with 'tenseness' (-0.69; the 'neglect' showed a weaker positive associated with 'frustration' (0.41, and a small negative association with 'tenseness' (-0.20. The model was a very good fit to the data (GFI  =  0.96; RSMR  =  0.07; AGFI = 0.96; NFI = 0.95; RFI = 0.95.The stress factors of 'frustration' and 'tenseness' seems to be related in a distinct way to the burnout subtypes in Spanish dental students. This finding suggests that intervention programs specifically tailored to these subtypes may be a promising future direction.

  6. Effects of distance from center of a weld to fixed end on residual stress and stress intensity factor of a piping weld. Evaluation of SCC growth under residual stress field. Report 1

    International Nuclear Information System (INIS)

    Miyazaki, Katsumasa; Numata, Masanori; Saito, Koichi; Mochizuki, Masahito

    2006-01-01

    The fixed conditions of butt welds between straight pipe and valve or pump in the actual piping system are different from those of straight pipes. However, the effect of fixed condition on the residual stress and the stress intensity factor for evaluation of structural integrity of cracked piping was not clear. In this study, the finite element analyses were conducted by considering the differences in the distance from the center of weld to the fixed end L to clarify the effect of fixed condition on the residual stress and the stress intensity factor. For the 600 A piping, the axial residual stress distribution was not affected by the distance L. Furthermore, the stress intensity factor of circumferential crack under the residual stress field with fixed condition could be estimated by using the existing simplified solution for piping. (author)

  7. Stress and psychological factors before a migraine attack: A time-based analysis

    Directory of Open Access Journals (Sweden)

    Makino Mariko

    2008-09-01

    Full Text Available Abstract Background The objective of this study is to examine the stress and mood changes of Japanese subjects over the 1–3 days before a migraine headache. Methods The study participants were 16 patients with migraines who consented to participate in this study. Each subject kept a headache diary four times a day for two weeks. They evaluated the number of stressful events, daily hassles, domestic and non-domestic stress, anxiety, depressive tendency and irritability by visual analog scales. The days were classified into migraine days, pre-migraine days, buffer days and control days based on the intensity of the headaches and accompanying symptoms, and a comparative study was conducted for each factor on the migraine days, pre-migraine days and control days. Results The stressful event value of pre-migraine days showed no significant difference compared to other days. The daily hassle value of pre-migraine days was the highest and was significantly higher than that of buffer days. In non-domestic stress, values on migraine days were significantly higher than on other days, and there was no significant difference between pre-migraine days and buffer days or between pre-migraine days and control days. There was no significant difference in the values of domestic stress between the categories. In non-domestic stress, values on migraine days were significantly higher than other days, and there was no significant difference between pre-migraine days and buffer days or between pre-migraine days and control days. There was little difference in sleep quality on migraine and pre-migraine days, but other psychological factors were higher on migraine days than on pre-migraine days. Conclusion Psychosocial stress preceding the onset of migraines by several days was suggested to play an important role in the occurrence of migraines. However, stress 2–3 days before a migraine attack was not so high as it has been reported to be in the United States and

  8. [Occupational stress in assembly line workers in electronics manufacturing service and related influencing factors].

    Science.gov (United States)

    Ji, Y Q; Li, S; Wang, C; Wang, J; Liu, X M

    2016-10-20

    Objective: To investigate occupational stress in assembly line workers in electronics manu-facturing service (EMS) and related influencing factors. Methods: From June to October, 2015, a cross-sectional survey was performed for 5 944 assembly line workers in EMS (observation group) and 6 270 workers from other posts (non-assembly line workers and management personnel; control group) using the self-made questionnaire for basic information, job demand-control (JDC) model questionnaire, and effort-reward imbalance (ERI) model questionnaire to collect respondents' basic information and occupational stress. Results: The observation group had significantly lower work autonomy, social support, and work reward scores than the control group (2.72 ± 0.63/3.64 ± 0.68/4.06 ± 0.80 vs 3.00 ± 0.67/3.83 ± 0.68/4.24 ± 0.75, t =23.53, 15.41, and 12.70, all P occupational stress determined by JDC and ERI models than the control group (64.5%/12.7% vs 52.6%/9.9%, χ 2 =182.26 and 23.41, both P 60 hours/week, and sleeping time occupational stress in JDC model; education background of Bachelor's degree or above, working time >60 hours/week, and sleeping timeoccupational stress in ERI model, while female sex and a high monthly income reduced the risk of occupational stress in ERI model. Conclusion: Assembly line workers in EMS are a relatively vulnerable group and have a high degree of occupational stress. Working time >60 hours/week and sleeping time occupational stress.

  9. Stress Causing Factors Among Teachers in Elementary Schools and Their Relationship with Demographic and Job Characteristics

    Directory of Open Access Journals (Sweden)

    Teuta Agai–Demjaha

    2015-07-01

    CONCLUSION: Our findings confirm that within the control category, the highest levels of perceived teacher’s work-related stress were caused by changes in terms and conditions without consultation and given responsibility without the authority to take decisions, while in the category support, the same was true for stress factors lack of funds/resources to do the job and limited or no access to training. We have also concluded that the lower-grade school teachers, female teachers, teachers for whom this is the first job and teachers with university education perceive more often the lack of authority to take decisions as a very stressful factor than the upper-grade school teachers, male teachers, teachers previously employed in another workplace, and those with high education. The lower-grade school teachers, older teachers and teachers with university education perceive more often changes in education as a very stressful factor than the upper grade school teachers, younger teachers and those with high education.

  10. A plastic stress intensity factor approach to turbine disk structural integrity assessment

    Directory of Open Access Journals (Sweden)

    V. Shlyannikov

    2016-07-01

    Full Text Available This study based on a new fracture mechanics parameter is concerned with assessing the integrity of cracked steam turbine disk which operate under startup-shutdown cyclic loading conditions. Damage accumulation and growth in service have occurred on the inner surface of slot fillet of key. In order to determine elastic-plastic fracture mechanics parameters full-size stress-strain state analysis of turbine disk was performed for a quote-elliptical part-through cracks under considering loading conditions. As a result distributions of elastic and plastic stress intensity factors along crack front in slot fillet of key of turbine disk depending on surface crack form are defined. An engineering approach to the prediction of carrying capacity of cracked turbine disk which is sensitive to the loading history at maintenance is proposed. The predictions of the rate of crack growth and residual lifetime of steam turbine disk are compared for elastic and elastic-plastic solutions. It is shown that the previously proposed elastic crack growth models provide overestimate the lifetime with respect to the present one. An advantage to use the plastic stress intensity factor to characterize the fracture resistance as the self-dependent unified parameter for a variety of turbine disk configurations rather than the magnitude of the elastic stress intensity factors alone is discussed.

  11. Influence of overelastic loading on the stress intensity factor under thermal fatigue conditions

    International Nuclear Information System (INIS)

    Stamm, H.; Munz, D.

    1983-10-01

    Thermal shock loading often creates high thermal stresses which may exceed yield strength of the material in a surface layer. In this report the application of the linear elastic ΔK-concept in the case of cyclic thermal loading within the shakedown region is discussed. To this K-factors for an edge crack in a linear elastic - perfectly plastic plate are calculated using the weight function method and are compared with results obtained with the Finite Element Method. It is shown, that rearrangement stresses during plastic flow in the first cycle must be taken into account developing conservative approximation procedures. (orig.) [de

  12. Are malnutrition and stress risk factors for accelerated cognitive decline? A prisoner of war study.

    Science.gov (United States)

    Sulway, M R; Broe, G A; Creasey, H; Dent, O F; Jorm, A F; Kos, S C; Tennant, C C

    1996-03-01

    We set out to test the hypothesis that severe malnutrition and stress experienced by prisoners of war (POWs) are associated with cognitive deficits later in life. We assessed 101 former Australian POWs of the Japanese and 108 veteran control subjects using a battery of neuropsychological tests, a depression scale, a clinical examination for dementia, and CT. We divided the POWs into high weight loss (>35%) and low weight loss groups (malnutrition is a risk factor for accelerated cognitive decline nor the theory that severe stress can lead to hippocampal neuronal loss and cognitive deficits. Cognitive deficits in earlier studies of former POWs may have been associated with concurrent depression.

  13. LUGS, Stress Analysis, Flexibility Factors for Rectangular Attachment on Thin Shell

    International Nuclear Information System (INIS)

    Dodge, W.G.

    1977-01-01

    1 - Description of problem or function: LUGS calculates stresses, stress indices, and flexibility factors for a rectangular attachment on a cylindrical shell. 2 - Method of solution: The program implements Bijlaard's series solution to the thin-shell equations. 3 - Restrictions on the complexity of the problem: Caution is recommended in using the code for attachments on very thin shells that have large circumferential dimension and small longitudinal dimension (GAMMA.GE.80, BETA2.LE.0.05, and BETA1.GE.0.3) as series convergence and/or numeric problems seem to exist

  14. Different intracellular distribution of avian reovirus core protein sigmaA in cells of avian and mammalian origin

    International Nuclear Information System (INIS)

    Vázquez-Iglesias, Lorena; Lostalé-Seijo, Irene; Martínez-Costas, José; Benavente, Javier

    2012-01-01

    A comparative analysis of the intracellular distribution of avian reovirus (ARV) core protein sigmaA in cells of avian and mammalian origin revealed that, whereas the viral protein accumulates in the cytoplasm and nucleolus of avian cells, most sigmaA concentrates in the nucleoplasm of mammalian cells in tight association with the insoluble nuclear matrix fraction. Our results further showed that sigmaA becomes arrested in the nucleoplasm of mammalian cells via association with mammalian cell-specific factors and that this association prevents nucleolar targeting. Inhibition of RNA polymerase II activity, but not of RNA polymerase I activity, in infected mammalian cells induces nucleus-to-cytoplasm sigmaA translocation through a CRM1- and RanGTP-dependent mechanism, yet a heterokaryon assay suggests that sigmaA does not shuttle between the nucleus and cytoplasm. The scarcity of sigmaA in cytoplasmic viral factories of infected mammalian cells could be one of the factors contributing to limited ARV replication in mammalian cells.

  15. Different intracellular distribution of avian reovirus core protein sigmaA in cells of avian and mammalian origin

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez-Iglesias, Lorena; Lostale-Seijo, Irene; Martinez-Costas, Jose [Departamento de Bioquimica y Biologia Molecular, Facultad de Farmacia, y Centro Singular de Investigacion en Quimica Biologica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782-Santiago de Compostela (Spain); Benavente, Javier, E-mail: franciscojavier.benavente@usc.es [Departamento de Bioquimica y Biologia Molecular, Facultad de Farmacia, y Centro Singular de Investigacion en Quimica Biologica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782-Santiago de Compostela (Spain)

    2012-10-25

    A comparative analysis of the intracellular distribution of avian reovirus (ARV) core protein sigmaA in cells of avian and mammalian origin revealed that, whereas the viral protein accumulates in the cytoplasm and nucleolus of avian cells, most sigmaA concentrates in the nucleoplasm of mammalian cells in tight association with the insoluble nuclear matrix fraction. Our results further showed that sigmaA becomes arrested in the nucleoplasm of mammalian cells via association with mammalian cell-specific factors and that this association prevents nucleolar targeting. Inhibition of RNA polymerase II activity, but not of RNA polymerase I activity, in infected mammalian cells induces nucleus-to-cytoplasm sigmaA translocation through a CRM1- and RanGTP-dependent mechanism, yet a heterokaryon assay suggests that sigmaA does not shuttle between the nucleus and cytoplasm. The scarcity of sigmaA in cytoplasmic viral factories of infected mammalian cells could be one of the factors contributing to limited ARV replication in mammalian cells.

  16. On the dimensionality of the stress-related growth scale: one, three, or seven factors?

    Science.gov (United States)

    Roesch, Scott C; Rowley, Anthony A; Vaughn, Allison A

    2004-06-01

    We examined the factorial validity and dimensionality of the Stress-Related Growth Scale (SRGS; Park, Cohen, & Murch, 1996) using a large multiethnic sample (n = 1,070). Exploratory and confirmatory factor analyses suggested that a multidimensional representation of the SRGS fit better than a unidimensional representation. Specifically, we cross-validated both a 3-factor model and a 7-factor model using confirmatory factor analysis and were shown to be invariant across gender and ethnic groups. The 3-factor model was represented by global dimensions of growth that included rational/mature thinking, affective/emotional growth, and religious/spiritual growth. We replicated the 7-factor model of Armeli, Gunthert, and Cohen (2001) and it represented more specific components of growth such as Self-Understanding and Treatment of Others. However, some factors of the 7-factor model had questionable internal consistency and were strongly intercorrelated, suggesting redundancy. The findings support the notion that the factor structure of both the original 1-factor and revised 7-factor models are unstable and that the 3-factor model developed in this research has more reliable psychometric properties and structure.

  17. Cocaine Effects on Dopaminergic Transmission Depend on a Balance between Sigma-1 and Sigma-2 Receptor Expression.

    Science.gov (United States)

    Aguinaga, David; Medrano, Mireia; Vega-Quiroga, Ignacio; Gysling, Katia; Canela, Enric I; Navarro, Gemma; Franco, Rafael

    2018-01-01

    Sigma σ 1 and σ 2 receptors are targets of cocaine. Despite sharing a similar name, the two receptors are structurally unrelated and their physiological role is unknown. Cocaine increases the level of dopamine, a key neurotransmitter in CNS motor control and reward areas. While the drug also affects dopaminergic signaling by allosteric modulations exerted by σ 1 R interacting with dopamine D 1 and D 2 receptors, the potential regulation of dopaminergic transmission by σ 2 R is also unknown. We here demonstrate that σ 2 R may form heteroreceptor complexes with D 1 but not with D 2 receptors. Remarkably σ 1 , σ 2 , and D 1 receptors may form heterotrimers with particular signaling properties. Determination of cAMP levels, MAP kinase activation and label-free assays demonstrate allosteric interactions within the trimer. Importantly, the presence of σ 2 R induces bias in signal transduction as σ 2 R ligands increase cAMP signaling whereas reduce MAP kinase activation. These effects, which are opposite to those exerted via σ 1 R, suggest that the D 1 receptor-mediated signaling depends on the degree of trimer formation and the differential balance of sigma receptor and heteroreceptor expression in acute versus chronic cocaine consumption. Although the physiological role is unknown, the heteroreceptor complex formed by σ 1 , σ 2 , and D 1 receptors arise as relevant to convey the cocaine actions on motor control and reward circuits and as a key factor in acquisition of the addictive habit.

  18. Cocaine Effects on Dopaminergic Transmission Depend on a Balance between Sigma-1 and Sigma-2 Receptor Expression

    Directory of Open Access Journals (Sweden)

    David Aguinaga

    2018-02-01

    Full Text Available Sigma σ1 and σ2 receptors are targets of cocaine. Despite sharing a similar name, the two receptors are structurally unrelated and their physiological role is unknown. Cocaine increases the level of dopamine, a key neurotransmitter in CNS motor control and reward areas. While the drug also affects dopaminergic signaling by allosteric modulations exerted by σ1R interacting with dopamine D1 and D2 receptors, the potential regulation of dopaminergic transmission by σ2R is also unknown. We here demonstrate that σ2R may form heteroreceptor complexes with D1 but not with D2 receptors. Remarkably σ1, σ2, and D1 receptors may form heterotrimers with particular signaling properties. Determination of cAMP levels, MAP kinase activation and label-free assays demonstrate allosteric interactions within the trimer. Importantly, the presence of σ2R induces bias in signal transduction as σ2R ligands increase cAMP signaling whereas reduce MAP kinase activation. These effects, which are opposite to those exerted via σ1R, suggest that the D1 receptor-mediated signaling depends on the degree of trimer formation and the differential balance of sigma receptor and heteroreceptor expression in acute versus chronic cocaine consumption. Although the physiological role is unknown, the heteroreceptor complex formed by σ1, σ2, and D1 receptors arise as relevant to convey the cocaine actions on motor control and reward circuits and as a key factor in acquisition of the addictive habit.

  19. Transcriptional profiling of Medicago truncatula under salt stress identified a novel CBF transcription factor MtCBF4 that plays an important role in abiotic stress responses

    Directory of Open Access Journals (Sweden)

    Su Zhen

    2011-07-01

    Full Text Available Abstract Background Salt stress hinders the growth of plants and reduces crop production worldwide. However, different plant species might possess different adaptive mechanisms to mitigate salt stress. We conducted a detailed pathway analysis of transcriptional dynamics in the roots of Medicago truncatula seedlings under salt stress and selected a transcription factor gene, MtCBF4, for experimental validation. Results A microarray experiment was conducted using root samples collected 6, 24, and 48 h after application of 180 mM NaCl. Analysis of 11 statistically significant expression profiles revealed different behaviors between primary and secondary metabolism pathways in response to external stress. Secondary metabolism that helps to maintain osmotic balance was induced. One of the highly induced transcription factor genes was successfully cloned, and was named MtCBF4. Phylogenetic analysis revealed that MtCBF4, which belongs to the AP2-EREBP transcription factor family, is a novel member of the CBF transcription factor in M. truncatula. MtCBF4 is shown to be a nuclear-localized protein. Expression of MtCBF4 in M. truncatula was induced by most of the abiotic stresses, including salt, drought, cold, and abscisic acid, suggesting crosstalk between these abiotic stresses. Transgenic Arabidopsis over-expressing MtCBF4 enhanced tolerance to drought and salt stress, and activated expression of downstream genes that contain DRE elements. Over-expression of MtCBF4 in M. truncatula also enhanced salt tolerance and induced expression level of corresponding downstream genes. Conclusion Comprehensive transcriptomic analysis revealed complex mechanisms exist in plants in response to salt stress. The novel transcription factor gene MtCBF4 identified here played an important role in response to abiotic stresses, indicating that it might be a good candidate gene for genetic improvement to produce stress-tolerant plants.

  20. Transcriptional profiling of Medicago truncatula under salt stress identified a novel CBF transcription factor MtCBF4 that plays an important role in abiotic stress responses

    Science.gov (United States)

    2011-01-01

    Background Salt stress hinders the growth of plants and reduces crop production worldwide. However, different plant species might possess different adaptive mechanisms to mitigate salt stress. We conducted a detailed pathway analysis of transcriptional dynamics in the roots of Medicago truncatula seedlings under salt stress and selected a transcription factor gene, MtCBF4, for experimental validation. Results A microarray experiment was conducted using root samples collected 6, 24, and 48 h after application of 180 mM NaCl. Analysis of 11 statistically significant expression profiles revealed different behaviors between primary and secondary metabolism pathways in response to external stress. Secondary metabolism that helps to maintain osmotic balance was induced. One of the highly induced transcription factor genes was successfully cloned, and was named MtCBF4. Phylogenetic analysis revealed that MtCBF4, which belongs to the AP2-EREBP transcription factor family, is a novel member of the CBF transcription factor in M. truncatula. MtCBF4 is shown to be a nuclear-localized protein. Expression of MtCBF4 in M. truncatula was induced by most of the abiotic stresses, including salt, drought, cold, and abscisic acid, suggesting crosstalk between these abiotic stresses. Transgenic Arabidopsis over-expressing MtCBF4 enhanced tolerance to drought and salt stress, and activated expression of downstream genes that contain DRE elements. Over-expression of MtCBF4 in M. truncatula also enhanced salt tolerance and induced expression level of corresponding downstream genes. Conclusion Comprehensive transcriptomic analysis revealed complex mechanisms exist in plants in response to salt stress. The novel transcription factor gene MtCBF4 identified here played an important role in response to abiotic stresses, indicating that it might be a good candidate gene for genetic improvement to produce stress-tolerant plants. PMID:21718548

  1. Correlation of Stress Concentration Factors for T-Welded Connections – Finite Element Simulations and Fatigue Behavior

    Directory of Open Access Journals (Sweden)

    Gerardo Terán Méndez

    Full Text Available Abstract The stress concentration factors (SCFs in welded connections usually occur at zones with high stress levels. Stress concentrations reduce the fatigue behavior of welded connections in offshore structures and cracking can develop. By using the grinding technique, cracking can be eliminated. Stress concentration factors are defined as a ratio of maximum stress at the intersection to nominal stress on the brace. Defining the stress concentration factor is an important stage in the fatigue behavior of welded connections. Several approaches have evolved for designing structures with the classical S-N approach for estimating total life. This work correlates to the stress concentration factors of T-welded connections and the fatigue behavior. Stress concentration factors were computed with the finite element employing 3D T-welded connections with intact and grinding depth conditions. Then, T-welded connections were constructed with A36 plate steel and welded with E6013 electrodes to obtain the stress-life (S-N approach. The methodology from previous works was used to compute the SCF and fabricate the T-welded connections. The results indicated that the grinding process could restore the fatigue life of the T-welded connections for SCFs values in the range of 1.29. This value can be considered to be a low SCF value in T-welded connection. However, for higher SCF values, the fatigue life decreased, compromising and reducing the structural integrity of the T-welded connections.

  2. [Job stress in locomotive attendants in a locomotive depot and related influencing factors].

    Science.gov (United States)

    Kang, L; Jia, X C; Lu, F; Zhou, W H; Chen, R

    2017-10-20

    Objective: To investigate the current status of job stress in locomotive attendants in a locomotive depot and related influencing factors. Methods: From 2012 to 2013, cluster sampling was used to select 1500 locomotive attendants in a locomotive depot in Zhengzhou Railway Bureau as respondents.The contents of the investigation included general data and occupational information.A job satisfaction questionnaire was used to investigate the degree of satisfaction, a depression scale was used to investigate the frequency of symptoms, and a daily stress scale was used to investigate the frequency of fatigue and stress. Results: There was a significant difference in depression score between locomotive attendants with different ages, working years, degrees of education, working situations of spouse, total monthly family incomes, numbers of times of attendanceat night, monthly numbers of times of attendance,ormonthly attendance times( P job satisfaction score between locomotive attendants with different ages,working years, degrees of education, working situations of spouse, total monthly family incomes, numbers of times of attendance at night, monthly attendance times,or ways to work( P job satisfaction( β =1.546)and monthly number of times of attendance,working years,attendance time at night,and degree of education were negatively correlated with job satisfaction( β =-0.185,-0.097,-0.020,and -1.106); monthly number of times of attendance andcommute time were positively correlated with depression( β =0.243 and 0.029); attendance time at night,working situation of spouse,commute time,monthly number of times of attendance,degree of education,and working years were positively correlated with daily stress( β =0.006,0.473,0.010,0.043,0.585, and 0.028). Conclusion: Number of times of attendance, attendance time,working years,and spouse are influencing factors for job stress in locomotive attendants. Improvement in work process and care for their personal life help to reduce

  3. Calculation of stress intensity factors for circumferential semi-elliptical cracks with high aspect ratio in pipes

    International Nuclear Information System (INIS)

    Zareei, A.; Nabavi, S.M.

    2016-01-01

    In this paper, stress intensity factors are calculated at the deepest point of an internal circumferential semi-elliptical crack in a pipe subjected to any arbitrary load. Based on the three dimensional finite element analysis, a weight function is proposed for high aspect ratio semi-elliptical cracks in pipes. An effective expression is developed analytically to evaluate the stress intensity factor using the weight function method. For several crack face stress fields and welding residual stress distributions, the weight function is validated against finite element data and those in the literature. Based on the comparison results, it can be concluded that the solution proposed in this paper is effective in engineering applications. - Highlights: • Analysis of internal circumferential semi-elliptical cracks with high aspect ratio in pipes. • A weight function is proposed for the calculation of the stress intensity factors for the deepest point of the crack. • An effective closed form expression is proposed to evaluate the stress intensity factors. • Prediction of stress intensity factors for any applied stress gradients through the wall thickness without any limitations. • A three-dimensional finite element modeling employs to calculate the stress intensity factors for different geometries.

  4. Abscisic-acid-dependent basic leucine zipper (bZIP) transcription factors in plant abiotic stress.

    Science.gov (United States)

    Banerjee, Aditya; Roychoudhury, Aryadeep

    2017-01-01

    One of the major causes of significant crop loss throughout the world is the myriad of environmental stresses including drought, salinity, cold, heavy metal toxicity, and ultraviolet-B (UV-B) rays. Plants as sessile organisms have evolved various effective mechanism which enable them to withstand this plethora of stresses. Most of such regulatory mechanisms usually follow the abscisic-acid (ABA)-dependent pathway. In this review, we have primarily focussed on the basic leucine zipper (bZIP) transcription factors (TFs) activated by the ABA-mediated signalosome. Upon perception of ABA by specialized receptors, the signal is transduced via various groups of Ser/Thr kinases, which phosphorylate the bZIP TFs. Following such post-translational modification of TFs, they are activated so that they bind to specific cis-acting sequences called abscisic-acid-responsive elements (ABREs) or GC-rich coupling elements (CE), thereby influencing the expression of their target downstream genes. Several in silico techniques have been adopted so far to predict the structural features, recognize the regulatory modification sites, undergo phylogenetic analyses, and facilitate genome-wide survey of TF under multiple stresses. Current investigations on the epigenetic regulation that controls greater accessibility of the inducible regions of DNA of the target gene to the bZIP TFs exclusively under stress situations, along with the evolved stress memory responses via genomic imprinting mechanism, have been highlighted. The potentiality of overexpression of bZIP TFs, either in a homologous or in a heterologous background, in generating transgenic plants tolerant to various abiotic stressors have also been addressed by various groups. The present review will provide a coherent documentation on the functional characterization and regulation of bZIP TFs under multiple environmental stresses, with the major goal of generating multiple-stress-tolerant plant cultivars in near future.

  5. Coping with stress and cognitive interference in student teachers performance as important factors influencing their achievement

    Directory of Open Access Journals (Sweden)

    Cirila Peklaj

    2001-06-01

    Full Text Available The purpose of our study was to investigate the relations between student teachers' strategies for coping with stressful situations, cognitive interference factors and successfulness of presentation of student teachers' seminar work. There were 135 student teachers participating in the study. At the beginning of the semester they filled in the Way of Coping Questionnaire (Folkman & Lazarus, 1988. After their presentation of seminar theme they reported about the cognitive interference factors during the presentation (distractive factors and intrusive thoughts. Different aspects of their performance were also evaluated by the teacher according to the well-known criteria. The analysis of the results showed significant correlations between certain ways of coping, cognitive interference factors and success of performance. Further statistical analysis showed significant differences in experiencing distractive factors and intrusive thoughts during presentation between students with low, medium and high performance success. The importance of successful strategies for coping with verbal presentation and the implications for student teacher education are discussed.

  6. Gender differences in the factor structure of posttraumatic stress disorder symptoms in war-exposed adolescents.

    Science.gov (United States)

    Armour, Cherie; Elhai, Jon D; Layne, Christopher M; Shevlin, Mark; Duraković-Belko, Elvira; Djapo, Nermin; Pynoos, Robert S

    2011-05-01

    DSM-IV's three-factor model of posttraumatic stress disorder (PTSD) is rarely empirically supported, whereas other four-factor models (King et al., 1998; Simms, Watson, & Doebbeling, 2002) have proven to be better representations of PTSD's latent structure. To date, a clear consensus as to which model provides the best representation of PTSD's underlying dimensions has yet to be reached. The current study investigated whether gender is associated with factor structure differences using the King et al. (1998) model of reexperiencing, avoidance, numbing, and hyperarousal PTSD symptoms. Participants were war-exposed Bosnian secondary/high school boys and girls (N=1572) assessed nearly two years after the 1992-1995 Bosnian conflict. Confirmatory factor analytic tests of measurement invariance across PTSD model parameters revealed many significant sex-linked differences. Implications regarding the potential role of gender as a moderator of the King et al. (1998) model's factor structure are discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Pipe stress intensity factors and coupled depressurization and dynamic crack propagation. 1976 Annual report

    International Nuclear Information System (INIS)

    Emery, A.F.; Kobayashi, A.S.; Love, W.J.

    1978-04-01

    This report contains the description of predictive models for the initiation and propagation of cracks in pipes and the numerical results obtained. The initiation of the crack was studied by evaluating stress intensity factors under static conditions for a series of representative flaws. Three-dimensional static stress intensity factors were determined for quarter-elliptical cracks at the corner of a hole in an infinite plate and at the corner of a bore in a rotating disk. Semi-elliptical cracks for plates in bending and in pressurized and thermally stressed hollow cylinders were also evaluated. The stress fields, in the absence of a crack, were used in the ''alternating technique'' to compute the stress intensity factors along the crack front. Parametric studies were made to assess the effects of crack thickness, the ratio of the major and minor axes of the ellipse and the thickness of the cylinders or plates. These parametric results may be used to predict critical flaw sizes for the initiation of the running crack. The initiation and propagation of axial through cracks in pressurized pipes was studied by using an elastic-plastic finite different shell code coupled with a one-dimensional thermal-hydraulic code which computed the leakage through the crack opening and the depressurization of the fluid in the pipe. The effects of large deflections and different fluid pressure profiles were investigated. The results showed that the crack opening shape is dependent upon the fracture criterion used and upon the average pressure on the crack flaps, but not upon the specific pressure profile. The consideration of large deflections changed the opening size of the crack and through the coupling with the pipe pressures, strongly affected the crack tip speed. However, for equal crack lengths, there was little difference between calculations made for large and small deflection

  8. Maternal Prenatal Stress and Other Developmental Risk Factors for Adolescent Depression: Spotlight on Sex Differences.

    Science.gov (United States)

    Maxwell, Seth D; Fineberg, Anna M; Drabick, Deborah A; Murphy, Shannon K; Ellman, Lauren M

    2018-02-01

    Maternal stress during pregnancy has been linked to premorbid abnormalities associated with depression (e.g., difficult temperament, cognitive deficits) in offspring. However, few studies have looked across developmental periods to examine maternal stress during pregnancy and offspring depression during adolescence and whether these associations differ by sex. The current study used data from 1711 mother-offspring dyads (offspring sex: 49.8% male) in a longitudinal birth cohort study. Maternal narratives collected during pregnancy were qualitatively coded for stress-related themes by independent raters. Latent class analysis (LCA) identified distinct subgroups of offspring based on exposure to maternal prenatal stress and other developmental factors from the prenatal, childhood, and adolescent periods that have been associated with depression and/or maternal prenatal stress. LCA identified subgroups that were compared to determine whether and to what extent they differed on adolescent depressive symptoms. LCA revealed a subgroup of "high-risk" individuals, characterized by maternal factors during pregnancy (higher ambivalence/negativity and lower positivity towards the pregnancy, higher levels of hassles, lower maternal education and higher maternal age at birth, higher pre-pregnancy BMI) and offspring developmental factors (decreased cognitive functioning during childhood and adolescence, lower perceived parental support during adolescence, and higher levels of maternal depression during adolescence). High-risk females exhibited elevated conduct symptoms and higher birth order, while high-risk males exhibited decreased internalizing symptoms and lower birth order. Both high-risk males and females reported elevated depressive symptoms during adolescence relative to their "low-risk" counterparts.

  9. Dutch monitor on stress and physical load: risk factors, consequences, and preventive action.

    Science.gov (United States)

    Houtman, I L; Goudswaard, A; Dhondt, S; van der Grinten, M P; Hildebrandt, V H; van der Poel, E G

    1998-02-01

    Due to recent changes in legislation on occupational health and safety, a national monitor on stress and physical load was developed in The Netherlands to monitor (a) risks and consequences of stress and physical load at work, (b) preventive actions in companies to reduce these risks, and (c) organisational and environmental variables that facilitate preventive actions. Information was gathered from employers, employees, and employees' representatives. The monitor was used with a nationally representative sample of companies in industry, wholesale trade, and banking and finance, 782 companies in total. The information from the employees, aggregated at the company level, was not found to be correlated with that from the employer from the same companies. Although many employers do recognise risk factors for both physical load and stress as a problem they often seem to underestimate the problem when compared with employees or their representatives. This is particularly the case for psychosocial risk factors. Also, the perception of outcome measures, especially employers who consider emotional exhaustion to be work related, were fewer than the employees' representatives of the same organisation. Preventive measures on physical load are much more popular than measures against stress. It is the responsibility of the employer to take more preventive action of all kinds. They need to recognise risk factors as problems and health outcomes to be related to work. Employees of larger companies should participate with employers to consider effective measures, and more use should be made of support at branch level. For specific preventive measures, specific predictors emerged. Except for measures to prevent work stress, information from employees did not sufficiently contribute to the initiation of preventive measures in the workplace.

  10. Transcription factors and plant response to drought stress: Current understanding and future directions

    Directory of Open Access Journals (Sweden)

    Rohit Joshi

    2016-07-01

    Full Text Available Increasing vulnerability of plants to a variety of stresses such as drought, salt and extreme temperatures poses a global threat to sustained growth and productivity of major crops. Of these stresses, drought represents a considerable threat to plant growth and development. In view of this, developing staple food cultivars with improved drought tolerance emerges as the most sustainable solution towards improving crop productivity in a scenario of climate change. In parallel, unraveling the genetic architecture and the targeted identification of molecular networks using modern OMICS analyses, that can underpin drought tolerance mechanisms, is urgently required. Importantly, integrated studies intending to elucidate complex mechanisms can bridge the gap existing in our current knowledge about drought stress tolerance in plants. It is now well established that drought tolerance is regulated by several genes, including transcription factors (TFs that enable plants to withstand unfavorable conditions, and these remain potential genomic candidates for their wide application in crop breeding. These TFs represent the key molecular switches orchestrating the regulation of plant developmental processes in response to a variety of stresses. The current review aims to offer a deeper understanding of TFs engaged in regulating plant’s response under drought stress and to devise potential strategies to improve plant tolerance against drought.

  11. Inhibition of Ribosome Recruitment Induces Stress Granule Formation Independently of Eukaryotic Initiation Factor 2α Phosphorylation

    Science.gov (United States)

    Mazroui, Rachid; Sukarieh, Rami; Bordeleau, Marie-Eve; Kaufman, Randal J.; Northcote, Peter; Tanaka, Junichi; Gallouzi, Imed

    2006-01-01

    Cytoplasmic aggregates known as stress granules (SGs) arise as a consequence of cellular stress and contain stalled translation preinitiation complexes. These foci are thought to serve as sites of mRNA storage or triage during the cell stress response. SG formation has been shown to require induction of eukaryotic initiation factor (eIF)2α phosphorylation. Herein, we investigate the potential role of other initiation factors in this process and demonstrate that interfering with eIF4A activity, an RNA helicase required for the ribosome recruitment phase of translation initiation, induces SG formation and that this event is not dependent on eIF2α phosphorylation. We also show that inhibition of eIF4A activity does not impair the ability of eIF2α to be phosphorylated under stress conditions. Furthermore, we observed SG assembly upon inhibition of cap-dependent translation after poliovirus infection. We propose that SG modeling can occur via both eIF2α phosphorylation-dependent and -independent pathways that target translation initiation. PMID:16870703

  12. Inhibition of ribosome recruitment induces stress granule formation independently of eukaryotic initiation factor 2alpha phosphorylation.

    Science.gov (United States)

    Mazroui, Rachid; Sukarieh, Rami; Bordeleau, Marie-Eve; Kaufman, Randal J; Northcote, Peter; Tanaka, Junichi; Gallouzi, Imed; Pelletier, Jerry

    2006-10-01

    Cytoplasmic aggregates known as stress granules (SGs) arise as a consequence of cellular stress and contain stalled translation preinitiation complexes. These foci are thought to serve as sites of mRNA storage or triage during the cell stress response. SG formation has been shown to require induction of eukaryotic initiation factor (eIF)2alpha phosphorylation. Herein, we investigate the potential role of other initiation factors in this process and demonstrate that interfering with eIF4A activity, an RNA helicase required for the ribosome recruitment phase of translation initiation, induces SG formation and that this event is not dependent on eIF2alpha phosphorylation. We also show that inhibition of eIF4A activity does not impair the ability of eIF2alpha to be phosphorylated under stress conditions. Furthermore, we observed SG assembly upon inhibition of cap-dependent translation after poliovirus infection. We propose that SG modeling can occur via both eIF2alpha phosphorylation-dependent and -independent pathways that target translation initiation.

  13. Cardiovascular Disease Risk Factors in Patients with Posttraumatic Stress Disorder (PTSD): A Narrative Review.

    Science.gov (United States)

    Šagud, Marina; Jakšić, Nenad; Vuksan-Ćusa, Bjanka; Lončar, Mladen; Lončar, Ivana; Peleš, Alma Mihaljević; Miličić, Davor; Jakovljević, Miro

    2017-12-01

    Posttraumatic stress disorder (PTSD) is a chronic condition related to severe stress and trauma. There is a mounting evidence about increased prevalence and mortality from cardiovascular diseases (CVD) in patients with PTSD. This review summarizes the current data on possible relations between PTSD and increased risks of CVD, including biological, psychological and behavioral factors. Biological factors refer to increased prevalence of metabolic syndrome (MetS), hypertension, elevation of pro-inflammatory cytokines and homocysteine levels. Peripheral Brain-derived neurotropic factor (BDNF), serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and quantitative electroencephalogram (qEEG) are promising surrogate markers of increased cardiovascular risk. Among psychological factors, some personality traits, such as neuroticism and trait impulsivity/hostility, contribute to the development of PTSD, and are associated with general cardiovascular distress. Recently, type-D (distressed) personality is usually investigated in relation to cardiovascular morbidity, but in populations other than PTSD patients. Behavioral factors refer to unhealthy life-styles, encompassing high smoking rate, drug substances abuse and addiction, physical inactivity and unhealthy diet. The relationships among all these factors are complex and yet incompletely taken into consideration. Because of a high prevalence of CVD in patients with PTSD, there is a strong need for a more intensive focus on this vulnerable population in both primary and secondary cardiovascular prevention as well as in effective treatment possibilities.

  14. Expression of a finger millet transcription factor, EcNAC1, in tobacco confers abiotic stress-tolerance.

    Directory of Open Access Journals (Sweden)

    Venkategowda Ramegowda

    Full Text Available NAC (NAM, ATAF1-2, and CUC2 proteins constitute one of the largest families of plant-specific transcription factors and have been shown to be involved in diverse plant processes including plant growth, development, and stress-tolerance. In this study, a stress-responsive NAC gene, EcNAC1, was isolated from the subtracted stress cDNA library generated from a drought adapted crop, finger millet, and characterized for its role in stress-tolerance. The expression analysis showed that EcNAC1 was highly induced during water-deficit and salt stress. EcNAC1 shares high amino acid similarity with rice genes that have been phylogenetically classified into stress-related NAC genes. Our results demonstrated that tobacco transgenic plants expressing EcNAC1 exhibit tolerance to various abiotic stresses like simulated osmotic stress, by polyethylene glycol (PEG and mannitol, and salinity stress. The transgenic plants also showed enhanced tolerance to methyl-viologen (MV induced oxidative stress. Reduced levels of reactive oxygen species (ROS and ROS-induced damage were noticed in pot grown transgenic lines under water-deficit and natural high light conditions. Root growth under stress and recovery growth after stress alleviation was more in transgenic plants. Many stress-responsive genes were found to be up-regulated in transgenic lines expressing EcNAC1. Our results suggest that EcNAC1 overexpression confers tolerance against abiotic stress in susceptible species, tobacco.

  15. Does Psychosocial Work Environment Factors Predict Stress and Mean Arterial Pressure in the Malaysian Industry Workers?

    Directory of Open Access Journals (Sweden)

    Muhammad Umair Javaid

    2018-01-01

    Full Text Available Psychosocial risks are considered as a burning issue in the Asia-Pacific region. The aim of this study was to investigate the impact of psychosocial work environment factors on health of petrochemical industry workers of Malaysia. In lieu to job demands-resources theory, significant positive associations were found between quantitative demands, work-family conflict, and job insecurity with stress, while a significant negative association of role clarity as a resource factor with stress was detected. We also found that quantitative demands were significantly associated with the mean arterial pressure (MAP. Multistage sampling procedure was used to collect study sample. Structural Equation Modeling was used to identify relationship between the endogenous and exogenous variables. Finally, the empirically tested psychosocial work environment model will further help in providing a better risk assessment in different industries and enterprises.

  16. Does Psychosocial Work Environment Factors Predict Stress and Mean Arterial Pressure in the Malaysian Industry Workers?

    Science.gov (United States)

    Javaid, Muhammad Umair; Isha, Ahmad Shahrul Nizam; Sabir, Asrar Ahmed; Ghazali, Zulkipli; Nübling, Matthias

    2018-01-01

    Psychosocial risks are considered as a burning issue in the Asia-Pacific region. The aim of this study was to investigate the impact of psychosocial work environment factors on health of petrochemical industry workers of Malaysia. In lieu to job demands-resources theory, significant positive associations were found between quantitative demands, work-family conflict, and job insecurity with stress, while a significant negative association of role clarity as a resource factor with stress was detected. We also found that quantitative demands were significantly associated with the mean arterial pressure (MAP). Multistage sampling procedure was used to collect study sample. Structural Equation Modeling was used to identify relationship between the endogenous and exogenous variables. Finally, the empirically tested psychosocial work environment model will further help in providing a better risk assessment in different industries and enterprises.

  17. Analysis of stress intensity factors for surface cracks in pre/post penetration

    International Nuclear Information System (INIS)

    Miyoshi, Toshiro; Yoshida, Yuichiro

    1988-01-01

    It is important to evaluate the penetration of surface cracks in a Leak-Before-Break analysis. Because the stress intensity factors for surface cracks in pre/post penetration had not yet been analyzed, the authors carried three-dimensional boundary element analyses in order to obtain them. First, the authors developed the technique of nodal breakdown appropriate for cracks with short ligament length in a two-dimensional boundary element analysis. Next, analyses of stress intensity factor for surface cracks in pre/post penetration were carried out using the technique of nodal breakdown for cracks with short ligament length and the three-dimensional boundary element code BEM 3 D which was designed for a supercomputer. (author)

  18. Effect of different stress factors on IL-6 and leptin expression in HELA cell cultures

    International Nuclear Information System (INIS)

    Chu Zhenwei; Yang Tao; Wang Luhuan; Hao Xiuhua; Yan Guangtao

    2009-01-01

    Objective: To study the effect of three stress factors high glucose (HG), lipopolysaccharide (LPS) and hydrogen peroxide (H 2 O 2 ) on the expression of culture supernatant IL-6 (IL-6) and leptin contents of HELA cell line. Methods: HELA cell culture models of severe inflammatory response syndrome were prepared with cultures treated with 50 mmol/L glucose (HG), 4 μg/ ml LPS and 100 μmol/L H 2 O 2 respectively and supernatant contents of IL-6 and leptin were measured with RIA at 1h, 6h and 24h. Results: Generally speaking, the culture supernatant contents of IL-6 gradually increased and leptin contents gradually decreased with significant differences from those in cultures not treated with either stress factor at 6h and 12h (P<0.05). Conclusion: Leptin as a possible anti-inflammatory cytokine might plays an important protective role in severe inflammatory response. (authors)

  19. Stress Intensity Factor for Interface Cracks in Bimaterials Using Complex Variable Meshless Manifold Method

    Directory of Open Access Journals (Sweden)

    Hongfen Gao

    2014-01-01

    Full Text Available This paper describes the application of the complex variable meshless manifold method (CVMMM to stress intensity factor analyses of structures containing interface cracks between dissimilar materials. A discontinuous function and the near-tip asymptotic displacement functions are added to the CVMMM approximation using the framework of complex variable moving least-squares (CVMLS approximation. This enables the domain to be modeled by CVMMM without explicitly meshing the crack surfaces. The enriched crack-tip functions are chosen as those that span the asymptotic displacement fields for an interfacial crack. The complex stress intensity factors for bimaterial interfacial cracks were numerically evaluated using the method. Good agreement between the numerical results and the reference solutions for benchmark interfacial crack problems is realized.

  20. Human Factors Effecting Forensic Decision Making: Workplace Stress and Well-being.

    Science.gov (United States)

    Jeanguenat, Amy M; Dror, Itiel E

    2018-01-01

    Over the past decade, there has been a growing openness about the importance of human factors in forensic work. However, most of it focused on cognitive bias, and neglected issues of workplace wellness and stress. Forensic scientists work in a dynamic environment that includes common workplace pressures such as workload volume, tight deadlines, lack of advancement, number of working hours, low salary, technology distractions, and fluctuating priorities. However, in addition, forensic scientists also encounter a number of industry-specific pressures, such as technique criticism, repeated exposure to crime scenes or horrific case details, access to funding, working in an adversarial legal system, and zero tolerance for "errors". Thus, stress is an important human factor to mitigate for overall error management, productivity and decision quality (not to mention the well-being of the examiners themselves). Techniques such as mindfulness can become powerful tools to enhance work and decision quality. © 2017 American Academy of Forensic Sciences.