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Sample records for repetitive units miru

  1. Effect of study design and setting on tuberculosis clustering estimates using Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats (MIRU-VNTR): a systematic review.

    Science.gov (United States)

    Mears, Jessica; Abubakar, Ibrahim; Cohen, Theodore; McHugh, Timothy D; Sonnenberg, Pam

    2015-01-21

    To systematically review the evidence for the impact of study design and setting on the interpretation of tuberculosis (TB) transmission using clustering derived from Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats (MIRU-VNTR) strain typing. MEDLINE, EMBASE, CINHAL, Web of Science and Scopus were searched for articles published before 21st October 2014. Studies in humans that reported the proportion of clustering of TB isolates by MIRU-VNTR were included in the analysis. Univariable meta-regression analyses were conducted to assess the influence of study design and setting on the proportion of clustering. The search identified 27 eligible articles reporting clustering between 0% and 63%. The number of MIRU-VNTR loci typed, requiring consent to type patient isolates (as a proxy for sampling fraction), the TB incidence and the maximum cluster size explained 14%, 14%, 27% and 48% of between-study variation, respectively, and had a significant association with the proportion of clustering. Although MIRU-VNTR typing is being adopted worldwide there is a paucity of data on how study design and setting may influence estimates of clustering. We have highlighted study design variables for consideration in the design and interpretation of future studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  2. Mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) genotyping of mycobacterium intracellulare for strain comparison with establishment of a PCR-based database.

    Science.gov (United States)

    Iakhiaeva, Elena; McNulty, Steven; Brown Elliott, Barbara A; Falkinham, Joseph O; Williams, Myra D; Vasireddy, Ravikiran; Wilson, Rebecca W; Turenne, Christine; Wallace, Richard J

    2013-02-01

    Strain comparison is important to population genetics and to evaluate relapses in patients with Mycobacterium avium complex (MAC) lung disease, but the "gold standard" of pulsed-field gel electrophoresis (PFGE) is time-consuming and complex. We used variable-number tandem repeats (VNTR) for fingerprinting of respiratory isolates of M. intracellulare from patients with underlying bronchiectasis, to establish a nonsequence-based database for population analysis. Different genotypes identified by PFGE underwent species identification using a 16S rRNA gene multiplex PCR. Genotypes of M. intracellulare were confirmed by internal transcribed spacer 1 (ITS1) sequencing and characterized using seven VNTR primers. The pattern of VNTR amplicon sizes and repeat number defined each specific VNTR type. Forty-two VNTR types were identified among 84 genotypes. PFGE revealed most isolates with the same VNTR type to be clonal or exhibit similar grouping of bands. Repetitive sequence-based PCR (rep-PCR) showed minimal pattern diversity between VNTR types compared to PFGE. Fingerprinting of relapse isolates from 31 treated patients using VNTR combined with 16S multiplex PCR unambiguously and reliably distinguished different genotypes from the same patient, with results comparable to those of PFGE. VNTR for strain comparison is easier and faster than PFGE, is as accurate as PFGE, and does not require sequencing. Starting with a collection of 167 M. intracellulare isolates, VNTR distinguished M. intracellulare into 42 clonal groups. Comparison of isolates from different geographic areas, habitats, and clinical settings is now possible.

  3. Comparison between RFLP and MIRU-VNTR genotyping of Mycobacterium tuberculosis strains isolated in Stockholm 2009 to 2011.

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    Jonsson, Jerker; Hoffner, Sven; Berggren, Ingela; Bruchfeld, Judith; Ghebremichael, Solomon; Pennhag, Alexandra; Groenheit, Ramona

    2014-01-01

    Our aim was to analyze the difference between methods for genotyping of Mycobacterium tuberculosis complex isolates. We collected genotyping results from Restriction Fragment Length Polymorphism (RFLP) and Mycobacterial Interspersed Repetitive Units-Variable Numbers of Tandem Repeat (MIRU-VNTR) in a geographically limited area (Stockholm) during a period of three years. The number and proportion of isolates belonging to clusters was reduced by 45 and 35% respectively when combining the two methods compared with using RFLP or MIRU-VNTR only. The mean size of the clusters was smaller when combining methods and smaller with RFLP compared to MIRU-VNTR. In clusters with confirmed epidemiological links RFLP coincided slightly better than MIRU-VNTR but where there was a difference, the variation in MIRU-VNTR pattern was only in a single locus. In isolates with few IS6110 bands in RFLP, MIRU-VNTR differentiated the isolates more, dividing the RFLP clusters. Since MIRU-VNTR is faster and less labour-intensive it is the method of choice for routine genotyping. In most cases it will be sufficient for epidemiological purposes but true clustering might still be considered if there are epidemiological links and the MIRU-VNTR results differ in only one of its 24 loci.

  4. The Epidemiological Significance and Temporal Stability of Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats-Based Method Applied to Mycobacterium tuberculosis in China

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    Yang Li

    2018-04-01

    Full Text Available This study aimed to validate the epidemiological significance and temporal stability of Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR typing in a genetically and geographically diverse set of clinical isolates from patients diagnosed with pulmonary tuberculosis in China. Between 2010 and 2013, a total of 982 Mycobacterium tuberculosis isolates were collected from four population-based investigations in China. Apart from the currently applied 24-locus MIRU-VNTR, six additional hypervariable loci were analyzed in order to validate the MIRU-VNTR combinations in terms of their epidemiological links, clustering time span, and paired geographic distance. In vitro temporal stability was analyzed for both individual MIRU-VNTR loci, and for several combinations of loci. In the present study, four MIRU-VNTR combinations, including the hypervariable loci 3820, 3232, 2163a, and 4120, were evaluated. All of these combinations obtained a Hunter-Gaston discriminatory index (HGDI value over 0.9900 with a reduced clustering proportion (from 32.0% to 25.6%. By comparing epidemiological links, clustering time span, and paired geographic distance, we found that the performances of the four MIRU-VNTR combinations were comparable to the insertion sequence 6110 restriction fragment length polymorphism (IS6110-RFLP, and significantly better than that of 24-locus MIRU-VNTR genotyping alone. The proportion of temporally stable loci ranged from 90.5% to 92.5% within the combined MIRU-VNTR genotyping, which is higher than IS6110-RFLP (85.4%. By adding four hypervariable loci to the standard 24-locus MIRU-VNTR genotyping, we obtained a high discriminatory power, stability and epidemiological significance. This algorithm could therefore be used to improve tuberculosis transmission surveillance and outbreak investigation in China.

  5. Evaluation of spoligotyping, SNPs and customised MIRU-VNTR combination for genotyping Mycobacterium tuberculosis clinical isolates in Madagascar.

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    Rasoahanitralisoa, Rondroarivelo; Rakotosamimanana, Niaina; Stucki, David; Sola, Christophe; Gagneux, Sebastien; Rasolofo Razanamparany, Voahangy

    2017-01-01

    Combining different molecular typing methods for Mycobacterium tuberculosis complex (MTBC) can be a powerful tool for molecular epidemiology-based investigation of TB. However, the current standard method that provides high discriminatory power for such a combination, mycobacterial interspersed repetitive units-variable numbers of tandem repeats typing (MIRU-VNTR), is laborious, time-consuming and often too costly for many resource-limited laboratories. We aimed to evaluate a reduced set of loci for MIRU-VNTR typing in combination with spoligotyping and SNP-typing for routine molecular epidemiology of TB. Spoligotyping and SNP-typing, in combination with the 15 loci MIRU-VNTR typing, were first used to type clinical MTBC isolates (n = 158) from Madagascar. A step by step reduction of MIRU-VNTR loci number was then performed according to the Hunter and Gaston Discriminatory Index (HGDI) and to the Principal component analysis (PCA) correlation with the spoligotype profiles to evaluate the discrimination power inside the generated spoligotype clusters. The 15 MIRU-VNTR was used as reference and SNP-typing was used to determine the main MTBC lineages. Of the 158 clinical isolates studied, the SNP-typing classified 23 into Lineage 1 (14.6%), 31 into Lineage 2 (19.6%), 23 into Lineage 3 (14.6%) and 81 into Lineage 4 strains (51.3%). 37 different spoligotypes profiles were obtained, 15 of which were unique and 20 in clusters. 15-loci MIRU-VNTR typing revealed 144 different genotypes: 132 isolates had a unique MIRU-VNTR profile and 27 isolates were grouped into 12 clusters. After a stepwise reduction of the MIRU-VNTR loci number within each main spoligotype families, three different sets composed of 5 customised MIRU-VNTR loci had a similar discrimination level to the reference 15 loci MIRU-VNTR in lineage 1, lineage 2 and lineage 3. For lineage 4, a set of 4 and 3 MIRU-VNTR loci were proposed to subtype the Harleem and LAM spoligotype families, respectively. For the T

  6. Different Mycobacterium avium subsp. paratuberculosis MIRU-VNTR patterns coexist within cattle herds.

    Science.gov (United States)

    van Hulzen, K J E; Heuven, H C M; Nielen, M; Hoeboer, J; Santema, W J; Koets, A P

    2011-03-24

    A better understanding of the biodiversity of Mycobacterium avium subsp. paratuberculosis (MAP) offers more insight in the epidemiology of paratuberculosis and therefore may contribute to the control of the disease. The aim of this study was to investigate the genetic diversity in bovine MAP isolates using PCR-based methods detecting genetic elements called Variable-Number Tandem Repeats (VNTRs) and Mycobacterial Interspersed Repetitive Units (MIRUs) to determine if multiple MAP strains can coexist on farms with endemic MAP infection. For 52 temporal isolates originating from infected cattle from 32 commercial dairy herds with known trading history, MIRU-VNTR analysis was applied at 10 loci of which six showed variation. Within the group of 52 isolates, 17 different MIRU-VNTR patterns were detected. One MIRU-VNTR pattern was found in 29 isolates, one pattern in four isolates, one pattern in three isolates, two times one MIRU-VNTR pattern was found occurring in two isolates, and 12 patterns were found only once. Eleven herds provided multiple isolates. In five herds a single MIRU-VNTR pattern was detected among multiple isolates whereas in six herds more than one pattern was found. This study confirms that between dairy farms as well as within dairy farms, infected animals shed MAP with different MIRU-VNTR patterns. Analysis of trading history and age within herds indicated that cows born within the same birth cohort can be infected with MAP strains exhibiting variations in the number of MIRU-VNTR repeats. These data indicate that such multiple genotypes of MAP can coexist within one herd. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Low genetic diversity of bovine Mycobacterium avium subspecies paratuberculosis isolates detected by MIRU-VNTR genotyping.

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    de Kruijf, Marcel; Lesniak, Olga N; Yearsley, Dermot; Ramovic, Elvira; Coffey, Aidan; O'Mahony, Jim

    2017-05-01

    Mycobacterial interspersed repetitive unit and variable number tandem repeat (MIRU-VNTR) has been developed as a simple, rapid and cost efficient molecular typing method to differentiate Mycobacterium avium subspecies paratuberculosis (MAP) isolates. The aim of this study was to determine the genomic diversity of MAP across the Republic of Ireland by utilising the MIRU-VNTR typing method on a large collection of MAP isolates. A total of 114 MAP isolates originated from 53 herds across 19 counties in the Republic of Ireland were genotyped based on eight established MIRU-VNTR loci. Four INMV groups were observed during this study. INMV 1 was found in 67 MAP isolates (58.8%) and INMV 2 was observed in 45 isolates (39.4%). INMV 3 and INMV 116 recorded only one isolate each (0.9%). The unique INMV 116 group has never been reported among herds thus far and the molecular pattern of the MAP isolate classified in INMV 116 showed a difference at the MIRU-VNTR X3 locus compared to the other three INMV groups observed. INMV 1, INMV 2 and INMV 3 are observed frequently in Europe and comprised 99.1% of the total MAP isolates characterised in this study, indicating that MAP exhibited low level of genetic diversity across the Republic of Ireland using the MIRU-VNTR method. By the implementation of SNP analysis or MLSSR as an additional typing method, MAP genetic diversity would increase. INMV 3 is unique to Ireland and whereas INMV 116 has never been previously reported among herds by MIRU-VNTR typing. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Mycobacterial Interspersed Repetitive-Unit–Variable-Number Tandem-Repeat (MIRU-VNTR) Genotyping of Mycobacterium intracellulare for Strain Comparison with Establishment of a PCR-Based Database

    Science.gov (United States)

    Iakhiaeva, Elena; McNulty, Steven; Brown Elliott, Barbara A.; Falkinham, Joseph O.; Williams, Myra D.; Vasireddy, Ravikiran; Wilson, Rebecca W.; Turenne, Christine

    2013-01-01

    Strain comparison is important to population genetics and to evaluate relapses in patients with Mycobacterium avium complex (MAC) lung disease, but the “gold standard” of pulsed-field gel electrophoresis (PFGE) is time-consuming and complex. We used variable-number tandem repeats (VNTR) for fingerprinting of respiratory isolates of M. intracellulare from patients with underlying bronchiectasis, to establish a nonsequence-based database for population analysis. Different genotypes identified by PFGE underwent species identification using a 16S rRNA gene multiplex PCR. Genotypes of M. intracellulare were confirmed by internal transcribed spacer 1 (ITS1) sequencing and characterized using seven VNTR primers. The pattern of VNTR amplicon sizes and repeat number defined each specific VNTR type. Forty-two VNTR types were identified among 84 genotypes. PFGE revealed most isolates with the same VNTR type to be clonal or exhibit similar grouping of bands. Repetitive sequence-based PCR (rep-PCR) showed minimal pattern diversity between VNTR types compared to PFGE. Fingerprinting of relapse isolates from 31 treated patients using VNTR combined with 16S multiplex PCR unambiguously and reliably distinguished different genotypes from the same patient, with results comparable to those of PFGE. VNTR for strain comparison is easier and faster than PFGE, is as accurate as PFGE, and does not require sequencing. Starting with a collection of 167 M. intracellulare isolates, VNTR distinguished M. intracellulare into 42 clonal groups. Comparison of isolates from different geographic areas, habitats, and clinical settings is now possible. PMID:23175249

  9. Comparison of semi-automated commercial rep-PCR fingerprinting, spoligotyping, 12-locus MIRU-VNTR typing and single nucleotide polymorphism analysis of the embB gene as molecular typing tools for Mycobacterium bovis.

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    Armas, Federica; Camperio, Cristina; Coltella, Luana; Selvaggini, Serena; Boniotti, Maria Beatrice; Pacciarini, Maria Lodovica; Di Marco Lo Presti, Vincenzo; Marianelli, Cinzia

    2017-08-04

    Highly discriminatory genotyping strategies are essential in molecular epidemiological studies of tuberculosis. In this study we evaluated, for the first time, the efficacy of the repetitive sequence-based PCR (rep-PCR) DiversiLab Mycobacterium typing kit over spoligotyping, 12-locus mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing and embB single nucleotide polymorphism (SNP) analysis for Mycobacterium bovis typing. A total of 49 M. bovis animal isolates were used. DNA was extracted and genomic DNA was amplified using the DiversiLab Mycobacterium typing kit. The amplified fragments were separated and detected using a microfluidics chip with Agilent 2100. The resulting rep-PCR-based DNA fingerprints were uploaded to and analysed using web-based DiversiLab software through Pearson's correlation coefficient. Rep-PCR DiversiLab grouped M. bovis isolates into ten different clusters. Most isolates sharing identical spoligotype, MIRU-VNTR profile or embB gene polymorphism were grouped into different rep-PCR clusters. Rep-PCR DiversiLab displayed greater discriminatory power than spoligotyping and embB SNP analysis but a lower resolution power than the 12-locus MIRU-VNTR analysis. MIRU-VNTR confirmed that it is superior to the other PCR-based methods tested here. In combination with spoligotyping and 12-locus MIRU-VNTR analysis, rep-PCR improved the discriminatory power for M. bovis typing.

  10. Automated High-Throughput Genotyping for Study of Global Epidemiology of Mycobacterium tuberculosis Based on Mycobacterial Interspersed Repetitive Units

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    Supply, Philip; Lesjean, Sarah; Savine, Evgueni; Kremer, Kristin; van Soolingen, Dick; Locht, Camille

    2001-01-01

    Large-scale genotyping of Mycobacterium tuberculosis is especially challenging, as the current typing methods are labor-intensive and the results are difficult to compare among laboratories. Here, automated typing based on variable-number tandem repeats (VNTRs) of genetic elements named mycobacterial interspersed repetitive units (MIRUs) in 12 mammalian minisatellite-like loci of M. tuberculosis is presented. This system combines analysis of multiplex PCRs on a fluorescence-based DNA analyzer with computerized automation of the genotyping. Analysis of a blinded reference set of 90 strains from 38 countries (K. Kremer et al., J. Clin. Microbiol. 37:2607–2618, 1999) demonstrated that it is 100% reproducible, sensitive, and specific for M. tuberculosis complex isolates, a performance that has not been achieved by any other typing method tested in the same conditions. MIRU-VNTRs can be used for analysis of the global genetic diversity of M. tuberculosis complex strains at different levels of evolutionary divergence. To fully exploit the portability of this typing system, a website was set up for the analysis of M. tuberculosis MIRU-VNTR genotypes via the Internet. This opens the way for global epidemiological surveillance of tuberculosis and should lead to novel insights into the evolutionary and population genetics of this major pathogen. PMID:11574573

  11. A quantitative and efficient approach to select MIRU-VNTR loci based on accumulation of the percentage differences of strains for discriminating divergent Mycobacterium tuberculosis sublineages.

    Science.gov (United States)

    Pan, Xin-Ling; Zhang, Chun-Lei; Nakajima, Chie; Fu, Jin; Shao, Chang-Xia; Zhao, Li-Na; Cui, Jia-Yi; Jiao, Na; Fan, Chang-Long; Suzuki, Yasuhiko; Hattori, Toshio; Li, Di; Ling, Hong

    2017-07-26

    Although several optimal mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) loci have been suggested for genotyping homogenous Mycobacterium tuberculosis, including the Beijing genotype, a more efficient and convenient selection strategy for identifying optimal VNTR loci is needed. Here 281 M. tuberculosis isolates were analyzed. Beijing genotype and non-Beijing genotypes were identified, as well as Beijing sublineages, according to single nucleotide polymorphisms. A total of 22 MIRU-VNTR loci were used for genotyping. To efficiently select optimal MIRU-VNTR loci, we established accumulations of percentage differences (APDs) between the strains among the different genotypes. In addition, we constructed a minimum spanning tree for clustering analysis of the VNTR profiles. Our findings showed that eight MIRU-VNTR loci displayed disparities in h values of ≥0.2 between the Beijing genotype and non-Beijing genotype isolates. To efficiently discriminate Beijing and non-Beijing genotypes, an optimal VNTR set was established by adding loci with APDs ranging from 87.2% to 58.8%, resulting in the construction of a nine-locus set. We also found that QUB11a is a powerful locus for separating ST10s (including ST10, STF and STCH1) and ST22s (including ST22 and ST8) strains, whereas a combination of QUB11a, QUB4156, QUB18, Mtub21 and QUB26 could efficiently discriminate Beijing sublineages. Our findings suggested that two nine-locus sets were not only efficient for distinguishing the Beijing genotype from non-Beijing genotype strains, but were also suitable for sublineage genotyping with different discriminatory powers. These results indicate that APD represents a quantitative and efficient approach for selecting MIRU-VNTR loci to discriminate between divergent M. tuberculosis sublineages.

  12. MIRU-VNTR typing of drug-resistant tuberculosis isolates in Greece.

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    Rovina, Nikoletta; Karabela, Simona; Constantoulakis, Pantelis; Michou, Vassiliki; Konstantinou, Konstantinos; Sgountzos, Vassileios; Roussos, Charis; Poulakis, Nikolaos

    2011-08-01

    The increasing immigration rate in Greece from countries with a high prevalence of Mycobacterium tuberculosis (MTB) and multidrug-resistant tuberculosis (MDR-TB) may have an impact οn the number of MDR-TB cases in Greece. The aim of this study was to genotypically characterize the MTB isolates from patients with pulmonary drug-resistant tuberculosis (DR-TB) in Greece, and to determine whether there is any association between the prevalent genotypes and drug resistance. Fifty-three drug-resistant MTB strains isolated from culture specimens of clinical material from native Greeks and immigrant patients with pulmonary tuberculosis were genotyped using the mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) method. The phylogenetically distinct groups of isolates identified were: the Beijing (34%), the LAM (11%), the Haarlem (24.5%), the Uganda I (9.4%), the Ural (3.8%), the Delhi/CAS (9.4%) and the Cameroon (3.8%) families. Greek patients were more likely to have monoresistant and polyresistant TB with the most prevalent isolates belonging to the Haarlem family. Among foreign-born patients with MDR-TB, the most prevalent genotypes belonged to the Beijing family. MIRU-VNTR rapidly obtained clinically useful genotyping data, by characterizing clonal MTB heterogeneity in the isolated strains. Our results underline the need for more effective antituberculosis control programs in order to control the expansion of DR-TB in Greece.

  13. Molecular Typing of Mycobacterium Tuberculosis Complex by 24-Locus Based MIRU-VNTR Typing in Conjunction with Spoligotyping to Assess Genetic Diversity of Strains Circulating in Morocco.

    Science.gov (United States)

    Bouklata, Nada; Supply, Philip; Jaouhari, Sanae; Charof, Reda; Seghrouchni, Fouad; Sadki, Khalid; El Achhab, Youness; Nejjari, Chakib; Filali-Maltouf, Abdelkarim; Lahlou, Ouafae; El Aouad, Rajae

    2015-01-01

    Standard 24-locus Mycobacterial Interspersed Repetitive Unit Variable Number Tandem Repeat (MIRU-VNTR) typing allows to get an improved resolution power for tracing TB transmission and predicting different strain (sub) lineages in a community. During 2010-2012, a total of 168 Mycobacterium tuberculosis Complex (MTBC) isolates were collected by cluster sampling from 10 different Moroccan cities, and centralized by the National Reference Laboratory of Tuberculosis over the study period. All isolates were genotyped using spoligotyping, and a subset of 75 was genotyped using 24-locus based MIRU-VNTR typing, followed by first line drug susceptibility testing. Corresponding strain lineages were predicted using MIRU-VNTRplus database. Spoligotyping resulted in 137 isolates in 18 clusters (2-50 isolates per cluster: clustering rate of 81.54%) corresponding to a SIT number in the SITVIT database, while 31(18.45%) patterns were unique of which 10 were labelled as "unknown" according to the same database. The most prevalent spoligotype family was LAM; (n = 81 or 48.24% of isolates, dominated by SIT42, n = 49), followed by Haarlem (23.80%), T superfamily (15.47%), >Beijing (2.97%), > U clade (2.38%) and S clade (1.19%). Subsequent 24-Locus MIRU-VNTR typing identified 64 unique types and 11 isolates in 5 clusters (2 to 3isolates per cluster), substantially reducing clusters defined by spoligotyping only. The single cluster of three isolates corresponded to two previously treated MDR-TB cases and one new MDR-TB case known to be contact a same index case and belonging to a same family, albeit residing in 3 different administrative regions. MIRU-VNTR loci 4052, 802, 2996, 2163b, 3690, 1955, 424, 2531, 2401 and 960 were highly discriminative in our setting (HGDI >0.6). 24-locus MIRU-VNTR typing can substantially improve the resolution of large clusters initially defined by spoligotyping alone and predominating in Morocco, and could therefore be used to better study tuberculosis

  14. Molecular analysis and MIRU-VNTR typing of Mycobacterium avium subsp. avium, 'hominissuis' and silvaticum strains of veterinary origin.

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    Rónai, Zsuzsanna; Csivincsik, Ágnes; Dán, Ádám; Gyuranecz, Miklós

    2016-06-01

    Besides Mycobacterium avium subsp. paratuberculosis (MAP), M. avium subsp. avium (MAA), M. avium subsp. silvaticum (MAS), and 'M. avium subsp. hominissuis' (MAH) are equally important members of M. avium complex, with worldwide distribution and zoonotic potential. Genotypic discrimination is a prerequisite to epidemiological studies which can facilitate disease prevention through revealing infection sources and transmission routes. The primary aim of this study was to identify the genetic diversity within 135 MAA, 62 MAS, and 84 MAH strains isolated from wild and domestic mammals, reptiles and birds. Strains were tested for the presence of large sequence polymorphism LSP(A)17 and were submitted to Mycobacterial interspersed repetitive units-variable-number tandem repeat (MIRU-VNTR) analysis at 8 loci, including MIRU1, 2, 3, and 4, VNTR25, 32, and 259, and MATR9. In 12 strains hsp65 sequence code type was also determined. LSP(A)17 was present only in 19.9% of the strains. All LSP(A)17 positive strains belonged to subspecies MAH. The discriminatory power of the MIRU-VNTR loci set used reached 0.9228. Altogether 54 different genotypes were detected. Within MAH, MAA, and MAS strains 33, 16, and 5 different genotypes were observed. The described genotypes were not restricted to geographic regions or host species, but proved to be subspecies specific. Our knowledge about MAS is limited due to isolation and identification difficulties. This is the first study including a large number of MAS field strains. Our results demonstrate the high diversity of MAH and MAA strains and the relative uniformity of MAS strains. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Genetic diversity based on MIRU-VNTR profile of isolates of Mycobacterium bovis from Mexican cattle.

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    Nava Vargas, Alejandro; Milián Suazo, Feliciano; Cantó Alarcón, Germinal Jorge; Rubio Venegas, Yezenia; Guerrero Solorio, Roberto; Rodríguez Hernández, Elba; Pizano Martìnez, Oscar

    2016-09-01

    Bovine tuberculosis (bTB) is a disease caused by Mycobacterium bovis (M. bovis), which affects cattle, animal species and humans. To determinate the genetic structure of strains of M. bovis in mexican cattle, 467 isolates obtained from 2009 to 2010 from different regions of Mexico with known spoligotype were included in the study. The isolates were genotyped by interspersed repeated mycobacterial units-variable number tandem repeats (MIRU-VNTR) obtaining 13 MIRU-VNTR groups. When combining MIRU-VNTR patterns with its spolygotypes, the Hunter genetic discrimination index (HGDI), we obtained 421 genetic patterns distributed in 17 groups. The HGDI for the total loci was 0.99. The locus that presented the higher HGDI was 2461 (0.857), while the locus with the lowest HGDI was 2686 (0.239). When we analyzed our results, using just 6 or 8 MIRU-VNTR we obtained an discriminatory power of 0.8499 and 0.8875 respectively indicating lower HGDI than 12 MIRU-VNTR locus. Copyright © 2016. Published by Elsevier B.V.

  16. Genetic Diversity of Mycobacterium tuberculosis Isolates from Assam, India: Dominance of Beijing Family and Discovery of Two New Clades Related to CAS1_Delhi and EAI Family Based on Spoligotyping and MIRU-VNTR Typing.

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    Devi, Kangjam Rekha; Bhutia, Rinchenla; Bhowmick, Shovonlal; Mukherjee, Kaustab; Mahanta, Jagadish; Narain, Kanwar

    2015-01-01

    Tuberculosis (TB) is one of the major public health concerns in Assam, a remote state located in the northeastern (NE) region of India. The present study was undertaken to explore the circulating genotypes of Mycobacterium tuberculosis complex (MTBC) in this region. A total of 189 MTBC strains were collected from smear positive pulmonary tuberculosis cases from different designated microscopy centres (DMC) from various localities of Assam. All MTBC isolates were cultured on Lowenstein-Jensen (LJ) media and subsequently genotyped using spoligotyping and 24-loci mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing. Spoligotyping of MTBC isolates revealed 89 distinct spoligo patterns. The most dominant MTBC strain belonged to Beijing lineage and was represented by 35.45% (n = 67) of total isolates, followed by MTBC strains belonging to Central Asian-Delhi (CAS/Delhi) lineage and East African Indian (EAI5) lineage. In addition, in the present study 43 unknown spoligo patterns were detected. The discriminatory power of spoligotyping was found to be 0.8637 based on Hunter Gaston Discriminatory Index (HGDI). On the other hand, 24-loci MIRU-VNTR typing revealed that out of total 189 MTBC isolates from Assam 185 (97.9%) isolates had unique MIRU-VNTR profiles and 4 isolates grouped into 2 clusters. Phylogenetic analysis of 67 Beijing isolates based on 24-loci MIRU-VNTR typing revealed that Beijing isolates from Assam represent two major groups, each comprising of several subgroups. Neighbour-Joining (NJ) phylogenetic tree analysis based on combined spoligotyping and 24-loci MIRU-VNTR data of 78 Non-Beijing isolates was carried out for strain lineage identification as implemented by MIRU-VNTRplus database. The important lineages of MTBC identified were CAS/CAS1_Delhi (41.02%, n = 78) and East-African-Indian (EAI, 33.33%). Interestingly, phylogenetic analysis of orphan (23.28%) MTBC spoligotypes revealed that majority of these orphan

  17. [Proposal of a five MIRU-VNTR panel to screen clinical isolates of Mycobacterium tuberculosis in Mexico].

    Science.gov (United States)

    Bolado-Martínez, Enrique; Candia-Plata, Maria Del Carmen; Zenteno-Cuevas, Roberto; Mendoza Damián, Fabiola; Avilés-Acosta, Magali; Álvarez-Hernández, Gerardo

    2015-11-01

    Tuberculosis is a public health problem across Mexico. This paper aims to select a panel, with a minimum number of repetitive elements (MIRU-VNTR) for genotypic characterization of Mycobacterium tuberculosis (M. tuberculosis) clinical isolates. In this study, a full panel of 24 MIRU-VNTR loci was used to discriminate 65 clinical isolates of M. tuberculosis from three different geographical regions of Mexico. Those loci with the highest discriminatory power were subsequently selected. The panel, including five loci, was obtained by selecting the highest values of allelic diversity among the genotypes obtained. The dendrogram, generated by the panel MIRU-VNTR 5, showed a high discriminatory power with 65 unique genotype profiles and formed clusters according to the geographical region of origin. The panel MIRU-VNTR 5 can be useful for characterizing clinical isolates of M. tuberculosis in Mexico. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  18. The effects of poliomyelitis on motor unit behavior during repetitive muscle actions: a case report.

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    Trevino, Michael A; Herda, Trent J; Cooper, Michael A

    2014-09-06

    Acute paralytic poliomyelitis is caused by the poliovirus and usually results in muscle atrophy and weakness occurring in the lower limbs. Indwelling electromyography has been used frequently to investigate the denervation and innervation characteristics of the affected muscle. Recently developed technology allows the decomposition of the raw surface electromyography signals into the firing instances of single motor units. There is limited information regarding this electromyographic decomposition in clinical populations. In addition, regardless of electromyographic methods, no study has examined muscle activation parameters during repetitive muscle actions in polio patients. Therefore, the purpose of this study was to examine the motor unit firing rates and electromyographic amplitude and center frequency of the vastus lateralis during 20 repetitive isometric muscle actions at 50% maximal voluntary contraction in healthy subjects and one patient that acquired acute paralytic poliomyelitis. One participant that acquired acute type III spinal poliomyelitis (Caucasian male, age = 29 yrs) at 3 months of age and three healthy participants (Caucasian females, age = 19.7 ± 2.1 yrs) participated in this study. The polio participant reported neuromuscular deficiencies as a result of disease in the hips, knees, buttocks, thighs, and lower legs. None of the healthy participants reported any current or ongoing neuromuscular diseases or musculoskeletal injuries. An acute bout of poliomyelitis altered motor unit behavior, such as, healthy participants displayed greater firing rates than the polio patient. The reduction in motor unit firing rates was likely a fatigue protecting mechanism since denervation via poliomyelitis results in a reduction of motorneurons. In addition, the concurrent changes in motor unit firing rates, electromyography amplitude and frequency for the polio participant would suggest that the entire motorneuron pool was utilized in each contraction unlike

  19. Evaluation of customised lineage-specific sets of MIRU-VNTR loci for genotyping Mycobacterium tuberculosis complex isolates in Ghana.

    Science.gov (United States)

    Asante-Poku, Adwoa; Nyaho, Michael Selasi; Borrell, Sonia; Comas, Iñaki; Gagneux, Sebastien; Yeboah-Manu, Dorothy

    2014-01-01

    Different combinations of variable number of tandem repeat (VNTR) loci have been proposed for genotyping Mycobacterium tuberculosis complex (MTBC). Existing VNTR schemes show different discriminatory capacity among the six human MTBC lineages. Here, we evaluated the discriminatory power of a "customized MIRU12" loci format proposed previously by Comas et al. based on the standard 24 loci defined by Supply et al. for VNTR-typing of MTBC in Ghana. One hundred and fifty-eight MTBC isolates classified into Lineage 4 and Lineage 5 were used to compare a customized lineage-specific panel of 12 MIRU-VNTR loci ("customized MIRU-12") to the standard MIRU-15 genotyping scheme. The resolution power of each typing method was determined based on the Hunter-Gaston- Discriminatory Index (HGDI). A minimal set of customized MIRU-VNTR loci for typing Lineages 4 (Euro-American) and 5 (M. africanum West African 1) strains from Ghana was defined based on the cumulative HGDI. Among the 106 Lineage 4 strains, the customized MIRU-12 identified a total of 104 distinct genotypes consisting of 2 clusters of 2 isolates each (clustering rate 1.8%), and 102 unique strains while standard MIRU-15 yielded a total of 105 different genotypes, including 1 cluster of 2 isolates (clustering rate: 0.9%) and 104 singletons. Among, 52 Lineage 5 isolates, customized MIRU-12 genotyping defined 51 patterns with 1 cluster of 2 isolates (clustering rate: 0.9%) and 50 unique strains whereas MIRU-15 classified all 52 strains as unique. Cumulative HGDI values for customized MIRU-12 for Lineages 4 and 5 were 0.98 respectively whilst that of standard MIRU-15 was 0.99. A union of loci from the customised MIRU-12 and standard MIRU-15 revealed a set of customized eight highly discriminatory loci: 4052, 2163B, 40, 4165, 2165, 10,16 and 26 with a cumulative HGDI of 0.99 for genotyping Lineage 4 and 5 strains from Ghana.

  20. The use of mycobacterial interspersed repetitive unit typing and whole genome sequencing to inform tuberculosis prevention and control activities.

    Science.gov (United States)

    Gilbert, Gwendolyn L; Sintchenko, Vitali

    2013-07-01

    Molecular strain typing of Mycobacterium tuberculosis has been possible for only about 20 years; it has significantly improved our understanding of the evolution and epidemiology of Mycobacterium tuberculosis and tuberculosis disease. Mycobacterial interspersed repetitive unit typing, based on 24 variable number tandem repeat unit loci, is highly discriminatory, relatively easy to perform and interpret and is currently the most widely used molecular typing system for tuberculosis surveillance. Nevertheless, clusters identified by mycobacterial interspersed repetitive unit typing sometimes cannot be confirmed or adequately defined by contact tracing and additional methods are needed. Recently, whole genome sequencing has been used to identify single nucleotide polymorphisms and other mutations, between genotypically indistinguishable isolates from the same cluster, to more accurately trace transmission pathways. Rapidly increasing speed and quality and reduced costs will soon make large scale whole genome sequencing feasible, combined with the use of sophisticated bioinformatics tools, for epidemiological surveillance of tuberculosis.

  1. Assembly of highly repetitive genomes using short reads: the genome of discrete typing unit III Trypanosoma cruzi strain 231.

    Science.gov (United States)

    Baptista, Rodrigo P; Reis-Cunha, Joao Luis; DeBarry, Jeremy D; Chiari, Egler; Kissinger, Jessica C; Bartholomeu, Daniella C; Macedo, Andrea M

    2018-02-14

    Next-generation sequencing (NGS) methods are low-cost high-throughput technologies that produce thousands to millions of sequence reads. Despite the high number of raw sequence reads, their short length, relative to Sanger, PacBio or Nanopore reads, complicates the assembly of genomic repeats. Many genome tools are available, but the assembly of highly repetitive genome sequences using only NGS short reads remains challenging. Genome assembly of organisms responsible for important neglected diseases such as Trypanosoma cruzi, the aetiological agent of Chagas disease, is known to be challenging because of their repetitive nature. Only three of six recognized discrete typing units (DTUs) of the parasite have their draft genomes published and therefore genome evolution analyses in the taxon are limited. In this study, we developed a computational workflow to assemble highly repetitive genomes via a combination of de novo and reference-based assembly strategies to better overcome the intrinsic limitations of each, based on Illumina reads. The highly repetitive genome of the human-infecting parasite T. cruzi 231 strain was used as a test subject. The combined-assembly approach shown in this study benefits from the reference-based assembly ability to resolve highly repetitive sequences and from the de novo capacity to assemble genome-specific regions, improving the quality of the assembly. The acceptable confidence obtained by analyzing our results showed that our combined approach is an attractive option to assemble highly repetitive genomes with NGS short reads. Phylogenomic analysis including the 231 strain, the first representative of DTU III whose genome was sequenced, was also performed and provides new insights into T. cruzi genome evolution.

  2. Grade repetition and parents' perception of hearing loss: An analysis of data from children in the United States.

    Science.gov (United States)

    Gilani, Sapideh; Roditi, Rachel; Bhattacharyya, Neil

    2017-03-01

    To determine whether parent-perceived hearing problems are associated with grade repetition among children in the United States. Retrospective cohort analysis of a contemporary national database. The National Survey of Children's Health 2011 to 2012 was analyzed. Hearing loss, as perceived and reported by parents, was categorized as: no hearing problem, history of a hearing problem, or current hearing problem. Children never repeating a grade versus repeating one or more grades (kindergarten-high school) were identified. Univariate statistics and multivariate logistic regression analyzed the association of hearing problems with grade repetition. Patients with mental retardation, autism, and attention-deficit/hyperactivity disorder were excluded from the analysis. After adjusting for race, sex, and poverty level, odds ratios for grade repetition were computed. Among 66.1 million (average age, 8.3 years, 49.0% male) children, 97.3% never had a hearing problem, 1.7% had a history of a hearing problem, and 1.0% had a current hearing problem. Overall, 7.1% repeated a grade. Grade repetition was reported in 6.9% of children without a hearing problem versus 9.4% with a history of a hearing problem and 19.3% with a current hearing problem (P hearing problem demonstrated an odds ratio of 1.9 (95% confidence interval 0.82-4.13) for grade repetition, whereas a current hearing problem demonstrated an odds ratio of 3.0 (1.90-4.80). Parents' perception of children's hearing problems is strongly associated with grade repetition. This trend is noticed in elementary school more than in high school. 4. Laryngoscope, 127:741-745, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Evaluation of customised lineage-specific sets of MIRU-VNTR loci for genotyping Mycobacterium tuberculosis complex isolates in Ghana.

    Directory of Open Access Journals (Sweden)

    Adwoa Asante-Poku

    Full Text Available BACKGROUND: Different combinations of variable number of tandem repeat (VNTR loci have been proposed for genotyping Mycobacterium tuberculosis complex (MTBC. Existing VNTR schemes show different discriminatory capacity among the six human MTBC lineages. Here, we evaluated the discriminatory power of a "customized MIRU12" loci format proposed previously by Comas et al. based on the standard 24 loci defined by Supply et al. for VNTR-typing of MTBC in Ghana. METHOD: One hundred and fifty-eight MTBC isolates classified into Lineage 4 and Lineage 5 were used to compare a customized lineage-specific panel of 12 MIRU-VNTR loci ("customized MIRU-12" to the standard MIRU-15 genotyping scheme. The resolution power of each typing method was determined based on the Hunter-Gaston- Discriminatory Index (HGDI. A minimal set of customized MIRU-VNTR loci for typing Lineages 4 (Euro-American and 5 (M. africanum West African 1 strains from Ghana was defined based on the cumulative HGDI. RESULTS AND CONCLUSION: Among the 106 Lineage 4 strains, the customized MIRU-12 identified a total of 104 distinct genotypes consisting of 2 clusters of 2 isolates each (clustering rate 1.8%, and 102 unique strains while standard MIRU-15 yielded a total of 105 different genotypes, including 1 cluster of 2 isolates (clustering rate: 0.9% and 104 singletons. Among, 52 Lineage 5 isolates, customized MIRU-12 genotyping defined 51 patterns with 1 cluster of 2 isolates (clustering rate: 0.9% and 50 unique strains whereas MIRU-15 classified all 52 strains as unique. Cumulative HGDI values for customized MIRU-12 for Lineages 4 and 5 were 0.98 respectively whilst that of standard MIRU-15 was 0.99. A union of loci from the customised MIRU-12 and standard MIRU-15 revealed a set of customized eight highly discriminatory loci: 4052, 2163B, 40, 4165, 2165, 10,16 and 26 with a cumulative HGDI of 0.99 for genotyping Lineage 4 and 5 strains from Ghana.

  4. Rapid clonal analysis of recurrent tuberculosis by direct MIRU-VNTR typing on stored isolates

    Directory of Open Access Journals (Sweden)

    de Viedma Darío

    2007-07-01

    Full Text Available Abstract Background The application of molecular tools to the analysis of tuberculosis has revealed examples of clonal complexity, such as exogenous reinfection, coinfection, microevolution or compartmentalization. The detection of clonal heterogeneity by standard genotyping approaches is laborious and often requires expertise. This restricts the rapid availability of Mycobacterium tuberculosis (MTB genotypes for clinical or therapeutic decision-making. A new PCR-based technique, MIRU-VNTR, has made it possible to genotype MTB in a time frame close to real-time fingerprinting. Our purpose was to evaluate the capacity of this technique to provide clinicians with a rapid discrimination between reactivation and exogenous reinfection and whether MIRU-VNTR makes it possible to obtain data directly from stored MTB isolates from recurrent episodes. Results We detected differences, between the MIRUtypes of recurrent isolates in 38.5% (5/13 of the cases studied. These included cases of i exogenous reinfection, often with more resistant strains, ii likely examples of microevolution, leading to the appearance of new clonal variants and iii a combination of microevolution, coinfection and competition. Conclusion MIRU-VNTR rapidly obtained clinically useful genotyping data in a challenging situation, directly from stored MTB isolates without subculturing them or purifying their DNA. Our results also mean that MIRU-VNTR could be applied for easy, rapid and affordable massive screening of collections of stored MTB isolates, which could establish the real dimension of clonal heterogeneity in MTB infection.

  5. S1 satellite DNA repetitive units display identical structure and overall variability in all Anatolian brown frog taxa.

    Science.gov (United States)

    Picariello, Orfeo; Feliciello, Isidoro; Chinali, Gianni

    2016-02-01

    S1 satellite DNA from Palearctic brown frogs has a species-specific structure in all European species. We characterized S1 satellite DNA from the Anatolian brown frogs Rana macrocnemis, R. camerani, and R. holtzi in order to define their taxonomic rank and the structure of this satellite in this frog lineage. Southern blots of genomic DNA digested with KpnI, EcoRV, NdeI, NheI, or StuI produced the same pattern of satellite DNA bands. Moreover, quantitative dot blots showed that this satellite DNA accounts for 0.1 % of the genome in all taxa. Analysis of the overall genomic variability of the S1a repeat sequence in specimens from various populations demonstrated that this repetitive unit also has the same size (476 bp), the same most common sequence (MCS) and the same overall variability in all three taxa, and also in R. macrocnemis tavasensis. The S1a repetitive unit presents three deletions of 9, 8 and 1 bp compared to the 494-bp S1a repeat from European frogs. The S1a MCS has three variable positions (sequence WWTK in positions 183-186), due to the presence of two repeat subpopulations with motifs AATG and WWTT in all taxa. Unlike previously analyzed mitochondrial and nuclear sequences that show considerable variations among these taxa, no difference could be detected in the structure and variability of the S1 satellite repetitive units. This suggests that these taxa should belong to a single species. Our results indicate that this satellite DNA variety probably formed when the Anatolian lineage radiated from common ancestor about 4 mya, and since then has maintained its structure in all four taxa examined.

  6. A first insight on the population structure of Mycobacterium tuberculosis complex as studied by spoligotyping and MIRU-VNTRs in Santiago, Chile.

    Science.gov (United States)

    Balcells, María Elvira; García, Patricia; Meza, Paulina; Peña, Carlos; Cifuentes, Marcela; Couvin, David; Rastogi, Nalin

    2015-01-01

    Tuberculosis (TB) remains a significant public health problem worldwide, but the ecology of the prevalent mycobacterial strains, and their transmission, can vary depending on country and region. Chile is a country with low incidence of TB, that has a geographically isolated location in relation to the rest of South American countries due to the Andes Mountains, but recent migration from neighboring countries has changed this situation. We aimed to assess the genotypic diversity of Mycobacterium tuberculosis complex (MTBC) strains in Santiago, Chile, and compare with reports from other Latin-American countries. We analyzed MTBC isolates from pulmonary tuberculosis cases collected between years 2008 and 2013 in Central Santiago, using two genotyping methods: spoligotyping and 12-loci mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTRs). Data obtained were analyzed and compared to the SITVIT2 database. Mean age of the patients was 47.5 years and 61% were male; 11.6% were migrants. Of 103 strains (1 isolate/patient) included, there were 56 distinct spoligotype patterns. Of these, 16 strains (15.5%) corresponded to orphan strains in the SITVIT2 database, not previously reported. Latin American and Mediterranean (LAM) (34%) and T (33%) lineages were the most prevalent strains, followed by Haarlem lineage (16.5%). Beijing family was scarcely represented with only two cases (1.9%), one of them isolated from a Peruvian migrant. The most frequent clustered spoligotypes were SIT33/LAM3 (10.7%), SIT53/T1 (8.7%), SIT50/H3 (7.8%), and SIT37/T3 (6.8%). We conclude that LAM and T genotypes are the most prevalent genotypes of MTBC in Santiago, Chile, and together correspond to almost two thirds of analyzed strains, which is similar to strain distribution reported from other countries of Latin America. Nevertheless, the high proportion of SIT37/T3, which was rarely found in other Latin American countries, may underline a specific history or

  7. Asynchronous recruitment of low-threshold motor units during repetitive, low-current stimulation of the human tibial nerve.

    Science.gov (United States)

    Dean, Jesse C; Clair-Auger, Joanna M; Lagerquist, Olle; Collins, David F

    2014-01-01

    Motoneurons receive a barrage of inputs from descending and reflex pathways. Much of our understanding about how these inputs are transformed into motor output in humans has come from recordings of single motor units during voluntary contractions. This approach, however, is limited because the input is ill-defined. Herein, we quantify the discharge of soleus motor units in response to well-defined trains of afferent input delivered at physiologically-relevant frequencies. Constant frequency stimulation of the tibial nerve (10-100 Hz for 30 s), below threshold for eliciting M-waves or H-reflexes with a single pulse, recruited motor units in 7/9 subjects. All 25 motor units recruited during stimulation were also recruited during weak (recruited more units (n = 3/25 at 10 Hz; n = 25/25 at 100 Hz) at shorter latencies (19.4 ± 9.4 s at 10 Hz; 4.1 ± 4.0 s at 100 Hz) than lower frequencies. When a second unit was recruited, the discharge of the already active unit did not change, suggesting that recruitment was not due to increased synaptic drive. After recruitment, mean discharge rate during stimulation at 20 Hz (7.8 Hz) was lower than during 30 Hz (8.6 Hz) and 40 Hz (8.4 Hz) stimulation. Discharge was largely asynchronous from the stimulus pulses with "time-locked" discharge occurring at an H-reflex latency with only a 24% probability. Motor units continued to discharge after cessation of the stimulation in 89% of trials, although at a lower rate (5.8 Hz) than during the stimulation (7.9 Hz). This work supports the idea that the afferent volley evoked by repetitive stimulation recruits motor units through the integration of synaptic drive and intrinsic properties of motoneurons, resulting in "physiological" recruitment which adheres to Henneman's size principle and results in relatively low discharge rates and asynchronous firing.

  8. Determination of circulating Mycobacterium tuberculosis strains and transmission patterns among TB patients in Iran, using 15 loci MIRU-VNTR

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    S Zamani

    2015-01-01

    Conclusions: MIRU-VNTR typing showed a high genetic diversity and suggests the possibility of transmission from Sistan–Baluchestan to other provinces of Iran. This method could be considered a suitable tool for studying the transmission routes of TB and leading to more appropriate measures for TB control. MIRU-VNTR typing leads to a much better understanding of the bacterial population structure and phylogenetic relationships between strains of MTB in different regions of Iran.

  9. Asynchronous recruitment of low-threshold motor units during repetitive, low-current stimulation of the human tibial nerve

    Directory of Open Access Journals (Sweden)

    Jesse eDean

    2014-12-01

    Full Text Available Motoneurons receive a barrage of inputs from descending and reflex pathways. Much of our understanding about how these inputs are transformed into motor output in humans has come from recordings of single motor units during voluntary contractions. This approach, however, is limited because the input is ill-defined. Herein, we quantify the discharge of soleus motor units in response to well-defined trains of afferent input delivered at physiologically-relevant frequencies. Constant frequency stimulation of the tibial nerve (10-100 Hz for 30 s, below threshold for eliciting M-waves or H-reflexes with a single pulse, recruited motor units in 7/9 subjects. All 25 motor units recruited during stimulation were also recruited during weak (<10% MVC voluntary contractions. Higher frequencies recruited more units (n=3/25 at 10 Hz; n=25/25 at 100 Hz at shorter latencies (19.4±9.4 s at 10 Hz; 4.1±4.0 s at 100 Hz than lower frequencies. When a second unit was recruited, the discharge of the already active unit did not change, suggesting that recruitment was not due to increased synaptic drive. After recruitment, mean discharge rate during stimulation at 20 Hz (7.8 Hz was lower than during 30 Hz (8.6 Hz and 40 Hz (8.4 Hz stimulation. Discharge was largely asynchronous from the stimulus pulses with time-locked discharge occurring at an H-reflex latency with only a 24% probability. Motor units discharged after the stimulation ended in 89% of trials, although at a lower rate (5.8 Hz than during the stimulation (7.9 Hz. This work supports the idea that the afferent volley evoked by repetitive stimulation recruits motor units through the integration of synaptic drive and intrinsic properties of motoneurons, resulting in physiological recruitment which adheres to Henneman's size principle and results in relatively low discharge rates and asynchronous firing.

  10. MIRU-VNTR allelic variability depends on Mycobacterium bovis clonal group identity.

    Science.gov (United States)

    Hauer, Amandine; Michelet, Lorraine; De Cruz, Krystel; Cochard, Thierry; Branger, Maxime; Karoui, Claudine; Henault, Sylvie; Biet, Franck; Boschiroli, María Laura

    2016-11-01

    The description of the population of M. bovis strains circulating in France from 1978 to 2013 has highlighted the discriminating power of the MLVA among predominant spoligotype groups. In the present study we aimed to characterize clonal groups via MLVA and to better understand the strain's population structure. MLVA was performed with eight MIRU-VNTR loci, most of them defined by the Venomyc European consortium. The discriminatory index of each MLVA loci was calculated for SB0120, SB0134, SB0121 and the "F4-family", the main spoligotype groups in France. Differences in global DI per spoligotype, but also by locus within each spoligotype, were observed, which strongly suggest the clonal complex nature of these major groups. These MLVA results were compared to those of other European countries where strain collections had been characterized (Spain, Portugal, Italy, Northern Ireland and Belgium). Overall, QUB 3232 and ETR D are respectively the most and the least discriminative loci, regardless of the strains geographical origin. However, marked DI differences are observed in the rest of the MIRU-VNTR loci, again highlighting that strain genetic variability in a country depends on the dominant existing clonal complexes. A web application for M. bovis, including spoligotyping and MIRU-VNTR typing data, was developed to allow inter-laboratory comparison of field isolates. In conclusion, combination of typing methods is required for M. bovis optimum discrimination and differentiation of groups of strains. Thus, the loci employed for MLVA in a country should be those which are the most discriminative for the clonal complexes which characterize their M. bovis population. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. ALARA review of the maintenance and repair jobs of repetitive high radiation dose at Kori Unit 3 and 4

    International Nuclear Information System (INIS)

    Cho, Y.H.; Moon, J.H.; Kang, C.S.; Lee, J.S.; Lee, D.H.

    2003-01-01

    The policy of maintaining occupational radiation dose (ORD) as low as reasonably achievable (ALARA) requires the effective reduction of ORD in the phases of design as well as operation of nuclear power plants. It has been identified that a predominant portion of ORD arises during maintenance and repair operations at nuclear power plants. The cost-effective reduction of ORD cannot be achieved without a comprehensive analysis of accumulated ORD data of existing nuclear power plants. To identify the jobs of repetitive high ORD, the ORD data of Kori Units 3 and 4 over 10-year period from 1986 to 1995 were compiled into the PC-based ORD database program. As the radiation job classification structure, 26 main jobs are considered, most of which are further subdivided into detailed jobs. According to the order of the collective dose values for 26 main jobs, 10 jobs of high collective dose are identified. As an ALARA review, then, top 10 jobs of high collective dose are statistically analyzed with regard to 1) dose rate, 2) crew number and 3) job frequency that are the factors determining the collective dose for the radiation job of interest. Through the ALARA review, main reasons causing to high collective dose values are identified as follows. The high collective dose of RCP maintenance job is mainly due to the large crew number and the high job frequency. The characteristics of refueling job are similar to those of RCP maintenance job. However, the high collective doses of SG-related jobs such as S/G nozzle dam job, S/G man-way job and S/G tube maintenance job are mainly due to high radiation dose rate. (author)

  12. Contribution of spoligotyping and MIRU-VNTRs to characterize prevalent Mycobacterium tuberculosis genotypes infecting tuberculosis patients in Morocco.

    Science.gov (United States)

    Chaoui, Imane; Zozio, Thierry; Lahlou, Ouafae; Sabouni, Radia; Abid, Mohammed; El Aouad, Rajae; Akrim, Mohammed; Amzazi, Said; Rastogi, Nalin; El Mzibri, Mohammed

    2014-01-01

    In the present study, Mycobacterium tuberculosis complex (MTBC) clinical isolates from culture-positive TB patients in Morocco were studied by spoligotyping and 12-loci MIRU-VNTR typing methods to characterize prevalent genotypes (n = 219 isolates from 208 patients). Spoligotyping resulted in 39 unique patterns and 167 strains in 30 clusters (2-50 strains per cluster). Comparison with international database showed that 29 of 39 unique patterns matched existing shared spoligotype international types (SITs). Nine shared types containing 10 strains were newly created (SIT 2891 to SIT 2899); this led to the description of 69 SITs with 206 strains and two orphan patterns. The most prevalent spoligotype was SIT42 (LAM; n = 50 or 24% of isolates). The repartition of strains according to major MTBC clades was as follows LAM (46.1%)> Haarlem (26%) >ill-defined T superfamily (22.6%) and S clade (0.96%). On the other hand, Beijing, CAS (Central Asian) and EAI (East-African Indian) strains were absent in this setting. Subsequent 12-Loci MIRU typing resulted in a total of 25 SIT/MIT clusters (n = 66 isolates, 2-6 isolates per cluster), with a resulting recent transmission rate of 22.3%. The MIRU-VNTR patterns corresponded to 69 MITs for 138 strains and 46 orphan patterns. The most frequent patterns were MIT43 (n = 8), MIT9 (n = 7) and MIT42 (n = 7). HGDI analysis of the 12 MIRU loci showed that loci 10, 23 and 40 were highly discriminative in our setting. The results also underlined the usefulness of spoligotyping and MIRU-VNTR to detect mixed infections among certain of our TB patients. Globally, the results obtained showed that TB is almost exclusively transmitted in Morocco through evolutionary-modern MTBC lineages belonging to principal genetic groups 2/3 strains (Haarlem, LAM, T), with a high level of biodiversity seen by MIRU typing. This study provides with a 1st global snapshot of MTBC population structure in Morocco, and validates the potential use of spoligotyping in

  13. MIRU-VNTR Genotyping of Mycobacterium tuberculosis Strains Using QIAxcel Technology: A Multicentre Evaluation Study.

    Science.gov (United States)

    Nikolayevskyy, Vladyslav; Trovato, Alberto; Broda, Agnieszka; Borroni, Emanuele; Cirillo, Daniela; Drobniewski, Francis

    2016-01-01

    Molecular genotyping of M.tuberculosis is an important laboratory tool in the context of emerging drug resistant TB. The standard 24-loci MIRU-VNTR typing includes PCR amplification followed by the detection and sizing of PCR fragments using capillary electrophoresis on automated sequencers or using agarose gels. The QIAxcel Advanced system might offer a cost-effective medium-throughput alternative. Performance characteristics of the QIAxcel Advanced platform for the standard 24 VNTR loci panel was evaluated at two centres on a total of 140 DNA specimens using automated capillary electrophoresis as a reference method. Additionally 4 hypervariable MIRU-VNTR loci were evaluated on 53 crude DNA extracts. The sizing accuracy, interlaboratory reproducibility and overall instrument's performance were assessed during the study. An overall concordance with the reference method was high reaching 98.5% and 97.6% for diluted genomic and crude DNA extracts respectively. 91.4% of all discrepancies were observed in fragments longer than 700bp. The concordance for hypervariable loci was lower except for locus 4120 (96.2%). The interlaboratory reproducibility agreement rates were 98.9% and 91.3% for standard and hypervariable loci, respectively. Overall performance of the QIAxcel platform for M.tuberculosis genotyping using a panel of standard loci is comparable to that of established methods for PCR fragments up to 700bp. Inaccuracies in sizing of longer fragments could be resolved through using in-house size markers or introduction of offset values. To conclude, the QiaXcel system could be considered an effective alternative to existing methods in smaller reference and regional laboratories offering good performance and shorter turnaround times.

  14. MIRU-VNTR Genotyping of Mycobacterium tuberculosis Strains Using QIAxcel Technology: A Multicentre Evaluation Study.

    Directory of Open Access Journals (Sweden)

    Vladyslav Nikolayevskyy

    Full Text Available Molecular genotyping of M.tuberculosis is an important laboratory tool in the context of emerging drug resistant TB. The standard 24-loci MIRU-VNTR typing includes PCR amplification followed by the detection and sizing of PCR fragments using capillary electrophoresis on automated sequencers or using agarose gels. The QIAxcel Advanced system might offer a cost-effective medium-throughput alternative.Performance characteristics of the QIAxcel Advanced platform for the standard 24 VNTR loci panel was evaluated at two centres on a total of 140 DNA specimens using automated capillary electrophoresis as a reference method. Additionally 4 hypervariable MIRU-VNTR loci were evaluated on 53 crude DNA extracts. The sizing accuracy, interlaboratory reproducibility and overall instrument's performance were assessed during the study.An overall concordance with the reference method was high reaching 98.5% and 97.6% for diluted genomic and crude DNA extracts respectively. 91.4% of all discrepancies were observed in fragments longer than 700bp. The concordance for hypervariable loci was lower except for locus 4120 (96.2%. The interlaboratory reproducibility agreement rates were 98.9% and 91.3% for standard and hypervariable loci, respectively. Overall performance of the QIAxcel platform for M.tuberculosis genotyping using a panel of standard loci is comparable to that of established methods for PCR fragments up to 700bp. Inaccuracies in sizing of longer fragments could be resolved through using in-house size markers or introduction of offset values. To conclude, the QiaXcel system could be considered an effective alternative to existing methods in smaller reference and regional laboratories offering good performance and shorter turnaround times.

  15. Repetitive Stress Injuries

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Repetitive Stress Injuries KidsHealth / For Teens / Repetitive Stress Injuries What's ... t had any problems since. What Are Repetitive Stress Injuries? Repetitive stress injuries (RSIs) are injuries that ...

  16. Repetition and the Concept of Repetition

    Directory of Open Access Journals (Sweden)

    Arne Grøn

    2013-11-01

    Full Text Available This paper offers a description of the meaning of the category of repetition. Firstly, it is pointed out that Constantin uses repetition as a concept that means the creation of epochs; the passing from Greece to Modernity is accomplished distinguishing between recollection, a concept that looks back to the past, and repetition, a concept that looks forward to future. Secondly, it is showed that the category of repetition, as a religious category, relates with what Climacus calls “ethic despair” and with what Vigilius calls “second ethics”; it is through repetition that it can be understood that sin finds its place in ethics and these shows the tension between it and dogmatics. And thirdly, it is showed that the descovery of the new category of repetition is a rediscovery of what Kierkegaard calls category of spirit; repetition has for its object the individuality, and coming to be oneself is what Kierkegaard undertands as liberty. At the end of the paper it is questioned if the category of repetition is inconsistent with the book Repetition.

  17. Use of a repetitive DNA probe to type clinical and environmental isolates of Aspergillus flavus from a cluster of cutaneous infections in a neonatal intensive care unit.

    Science.gov (United States)

    James, M J; Lasker, B A; McNeil, M M; Shelton, M; Warnock, D W; Reiss, E

    2000-10-01

    Aspergillus flavus is second to A. fumigatus as a cause of invasive aspergillosis, but no standard method exists for molecular typing of strains from human sources. A repetitive DNA sequence cloned from A. flavus and subcloned into a pUC19 vector, pAF28, was used to type 18 isolates from diverse clinical, environmental, and geographic sources. The restriction fragment length polymorphisms generated with EcoRI- or PstI-digested genomic DNA and probed with digoxigenin-labeled pAF28 revealed complete concordance between patterns. Eighteen distinct fingerprints were observed. The probe was used to investigate two cases of cutaneous A. flavus infection in low-birth-weight infants in a neonatal intensive care unit (NICU). Both infants were transported by the same ambulance and crew to the NICU on the same day. A. flavus strains of the same genotype were isolated from both infants, from a roll of tape used to fasten their umbilical catheters, from a canvas bag used to store the tape in the ambulance, and from the tape tray in the ambulance isolette. These cases highlight the need to consider exposures in critically ill neonates that might occur during their transport to the NICU and for stringent infection control practices. The hybridization profiles of strains from a second cluster of invasive A. flavus infections in two pediatric hematology-oncology patients revealed a genotype common to strains from a definite case patient and a health care worker. A probable case patient was infected with a strain with a genotype different from that of the strain from the definite case patient but highly related to that of an environmental isolate. The high degree of discrimination and reproducibility obtained with the pAF28 probe underscores its utility for typing clinical and environmental isolates of A. flavus.

  18. MIRU-VNTR genotype diversity and indications of homoplasy in M. avium strains isolated from humans and slaughter pigs in Latvia.

    Science.gov (United States)

    Kalvisa, Adrija; Tsirogiannis, Constantinos; Silamikelis, Ivars; Skenders, Girts; Broka, Lonija; Zirnitis, Agris; Jansone, Inta; Ranka, Renate

    2016-09-01

    Diseases which are caused by non-tuberculous mycobacteria (NTM) are an increasing problem in the developed countries. In Latvia, one of the most clinically important members of NTM is Mycobacterium avium (M. avium), an opportunistic pathogen which has been isolated from several lung disease patients and tissue samples of slaughter pigs. This study was designed to characterize the genetic diversity of the M. avium isolates in Latvia and to compare the distribution of genotypic patterns among humans and pigs. Eleven (Hall and Salipante, 2010) clinical M. avium samples, isolated from patients of Center of Tuberculosis and Lung Diseases (years 2003-2010), and 32 isolates from pig necrotic mesenterial lymph nodes in different regions (years 2003-2007) were analyzed. The majority (42 of 43) of samples were identified as M. avium subsp. hominissuis; one porcine isolate belonged to M. avium subsp. avium. MIRU-VNTR genotyping revealed 13 distinct genotypes, among which nine genotype patterns, including M. avium subsp. avium isolate, were newly identified. IS1245 RFLP fingerprinting of 25 M. avium subsp. hominissuis samples yielded 17 different IS1245 RFLP patterns, allowing an efficient discrimination of isolates. Clusters of identical RFLP profiles were observed within host species, geographical locations and time frame of several years. Additional in silico analysis on simulated MIRU-VNTR genotype population datasets showed that the MIRU-VNTR pattern similarity could partly arise due to probabilistic increase of acquiring homoplasy among subpopulations, thus the similar MIRU-VNTR profiles of M. avium strains even in close geographical proximity should be interpreted with caution. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Roles of repetitive sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bell, G.I.

    1991-12-31

    The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

  20. Repetition and Translation Shifts

    Directory of Open Access Journals (Sweden)

    Simon Zupan

    2006-06-01

    Full Text Available Repetition manifests itself in different ways and at different levels of the text. The first basic type of repetition involves complete recurrences; in which a particular textual feature repeats in its entirety. The second type involves partial recurrences; in which the second repetition of the same textual feature includes certain modifications to the first occurrence. In the article; repetitive patterns in Edgar Allan Poe’s short story “The Fall of the House of Usher” and its Slovene translation; “Konec Usherjeve hiše”; are compared. The author examines different kinds of repetitive patterns. Repetitions are compared at both the micro- and macrostructural levels. As detailed analyses have shown; considerable microstructural translation shifts occur in certain types of repetitive patterns. Since these are not only occasional; sporadic phenomena; but are of a relatively high frequency; they reduce the translated text’s potential for achieving some of the gothic effects. The macrostructural textual property particularly affected by these shifts is the narrator’s experience as described by the narrative; which suffers a reduction in intensity.

  1. Genomic Variability of Mycobacterium tuberculosis Strains of the Euro-American Lineage Based on Large Sequence Deletions and 15-Locus MIRU-VNTR Polymorphism

    Science.gov (United States)

    Rindi, Laura; Medici, Chiara; Bimbi, Nicola; Buzzigoli, Andrea; Lari, Nicoletta; Garzelli, Carlo

    2014-01-01

    A sample of 260 Mycobacterium tuberculosis strains assigned to the Euro-American family was studied to identify phylogenetically informative genomic regions of difference (RD). Mutually exclusive deletions of regions RD115, RD122, RD174, RD182, RD183, RD193, RD219, RD726 and RD761 were found in 202 strains; the RDRio deletion was detected exclusively among the RD174-deleted strains. Although certain deletions were found more frequently in certain spoligotype families (i.e., deletion RD115 in T and LAM, RD174 in LAM, RD182 in Haarlem, RD219 in T and RD726 in the “Cameroon” family), the RD-defined sublineages did not specifically match with spoligotype-defined families, thus arguing against the use of spoligotyping for establishing exact phylogenetic relationships between strains. Notably, when tested for katG463/gyrA95 polymorphism, all the RD-defined sublineages belonged to Principal Genotypic Group (PGG) 2, except sublineage RD219 exclusively belonging to PGG3; the 58 Euro-American strains with no deletion were of either PGG2 or 3. A representative sample of 197 isolates was then analyzed by standard 15-locus MIRU-VNTR typing, a suitable approach to independently assess genetic relationships among the strains. Analysis of the MIRU-VNTR typing results by using a minimum spanning tree (MST) and a classical dendrogram showed groupings that were largely concordant with those obtained by RD-based analysis. Isolates of a given RD profile show, in addition to closely related MIRU-VNTR profiles, related spoligotype profiles that can serve as a basis for better spoligotype-based classification. PMID:25197794

  2. Repetitive Questioning Exasperates Caregivers

    Directory of Open Access Journals (Sweden)

    R. C. Hamdy MD

    2018-01-01

    Full Text Available Repetitive questioning is due to an impaired episodic memory and is a frequent, often presenting, problem in patients with Alzheimer’s disease (amnestic type. It is due to the patients’ difficulties learning new information, retaining it, and recalling it, and is often aggravated by a poor attention span and easy distractibility. A number of factors may trigger and maintain repetitive questioning. Caregivers should try to identify and address these triggers. In the case discussion presented, it is due to the patient’s concerns about her and her family’s safety triggered by watching a particularly violent movie aired on TV. What went wrong in the patient/caregiver interaction and how it could have been avoided or averted are explored. Also reviewed are the impact of repetitive questioning, the challenges it raises for caregivers, and some effective intervention strategies that may be useful to diffuse the angst that caregivers experience with repetitive questioning.

  3. Trends and differences in tuberculosis incidences and clustering among natives in Denmark, Sweden and Finland

    DEFF Research Database (Denmark)

    Pedersen, M K; Lillebaek, T; Andersen, A B

    2018-01-01

    among the countries. In addition, for the periods 2012-2013 and 2014-2015, genotyping data were compared. Genotyping was performed using the 24-locus mycobacterial interspersed repetitive unit-variable number of tandem repeat (MIRU-VNTR) method in Denmark and Sweden. For Finland, spoligotyping...... in conjunction with the 15-locus MIRU-VNTR method was used for 2012-2013 and translated into the 24-locus MIRU-VNTR when feasible, and for 2014-2015 only MIRU-VNTR was used. Both incidence trends and molecular epidemiology were assessed for native cases. RESULTS: The average annual rate of change in TB incidence...

  4. V-SINEs: A New Superfamily of Vertebrate SINEs That Are Widespread in Vertebrate Genomes and Retain a Strongly Conserved Segment within Each Repetitive Unit

    Science.gov (United States)

    Ogiwara, Ikuo; Miya, Masaki; Ohshima, Kazuhiko; Okada, Norihiro

    2002-01-01

    We have identified a new superfamily of vertebrate short interspersed repetitive elements (SINEs), designated V-SINEs, that are widespread in fishes and frogs. Each V-SINE includes a central conserved domain preceded by a 5′-end tRNA-related region and followed by a potentially recombinogenic (TG)n tract, with a 3′ tail derived from the 3′ untranslated region (UTR) of the corresponding partner long interspersed repetitive element (LINE) that encodes a functional reverse transcriptase. The central domain is strongly conserved and is even found in SINEs in the lamprey genome, suggesting that V-SINEs might be ∼550 Myr old or older in view of the timing of divergence of the lamprey lineage from the bony fish lineage. The central conserved domain might have been subject to some form of positive selection. Although the contemporary 3′ tails of V-SINEs differ from one another, it is possible that the original 3′ tail might have been replaced, via recombination, by the 3′ tails of more active partner LINEs, thereby retaining retropositional activity and the ability to survive for long periods on the evolutionary time scale. It seems plausible that V-SINEs may have some function(s) that have been maintained by the coevolution of SINEs and LINEs during the evolution of vertebrates. [The sequences reported in this paper have been deposited in the DDBJ/GenBank database under accession nos. AB072981–AB073004. Supplemental figures are available online at http://www.genome.org.] PMID:11827951

  5. Novel porcine repetitive elements

    Directory of Open Access Journals (Sweden)

    Nonneman Dan J

    2006-12-01

    Full Text Available Abstract Background Repetitive elements comprise ~45% of mammalian genomes and are increasingly known to impact genomic function by contributing to the genomic architecture, by direct regulation of gene expression and by affecting genomic size, diversity and evolution. The ubiquity and increasingly understood importance of repetitive elements contribute to the need to identify and annotate them. We set out to identify previously uncharacterized repetitive DNA in the porcine genome. Once found, we characterized the prevalence of these repeats in other mammals. Results We discovered 27 repetitive elements in 220 BACs covering 1% of the porcine genome (Comparative Vertebrate Sequencing Initiative; CVSI. These repeats varied in length from 55 to 1059 nucleotides. To estimate copy numbers, we went to an independent source of data, the BAC-end sequences (Wellcome Trust Sanger Institute, covering approximately 15% of the porcine genome. Copy numbers in BAC-ends were less than one hundred for 6 repeat elements, between 100 and 1000 for 16 and between 1,000 and 10,000 for 5. Several of the repeat elements were found in the bovine genome and we have identified two with orthologous sites, indicating that these elements were present in their common ancestor. None of the repeat elements were found in primate, rodent or dog genomes. We were unable to identify any of the replication machinery common to active transposable elements in these newly identified repeats. Conclusion The presence of both orthologous and non-orthologous sites indicates that some sites existed prior to speciation and some were generated later. The identification of low to moderate copy number repetitive DNA that is specific to artiodactyls will be critical in the assembly of livestock genomes and studies of comparative genomics.

  6. Repetitive Questioning II

    Directory of Open Access Journals (Sweden)

    R. C. Hamdy MD

    2018-02-01

    Full Text Available Repetitive questioning is a major problem for caregivers, particularly taxing if they are unable to recognize and understand the reasons why their loved one keeps asking the same question over and over again. Caregivers may be tempted to believe that the patient does not even try to remember the answer given or is just getting obnoxious. This is incorrect. Repetitive questioning is due to the underlying disease: The patient’s short term memory is impaired and he is unable to register, encode, retain and retrieve the answer. If he is concerned about a particular topic, he will keep asking the same question over and over again. To the patient each time she asks the question, it is as if she asked it for the first time. Just answering repetitive questioning by providing repeatedly the same answer is not sufficient. Caregivers should try to identify the underlying cause for this repetitive questioning. In an earlier case study, the patient was concerned about her and her family’s safety and kept asking whether the doors are locked. In this present case study, the patient does not know how to handle the awkward situation he finds himself in. He just does not know what to do. He is not able to adjust to the new unexpected situation. So he repeatedly wants to reassure himself that he is not intruding by asking the same question over and over again. We discuss how the patient’s son-in-law could have avoided this situation and averted the catastrophic ending.

  7. A NOR-associated repetitive element present in the genome of two Salmo species (Salmo salar and S. trutta)

    Digital Repository Service at National Institute of Oceanography (India)

    Abuin, M.; Clabby, C.; Martinez, P.; Goswami, U.; Flavin, F.; Wilkins, N.P.; Houghton, J.A.; Powell, R.; Sanchez, L.

    , internal repetition, and long direct repeats with deletions and insertions between individual units. The repetitive element was shown to have a tandem unit arrangement and was estimated to occupy between two and three percent of the Atlantic salmon genome...

  8. Genomic diversity of Mycobacterium tuberculosis Beijing strains isolated in Tuscany, Italy, based on large sequence deletions, SNPs in putative DNA repair genes and MIRU-VNTR polymorphisms.

    Science.gov (United States)

    Garzelli, Carlo; Lari, Nicoletta; Rindi, Laura

    2016-03-01

    The Beijing genotype of Mycobacterium tuberculosis is cause of global concern as it is rapidly spreading worldwide, is considered hypervirulent, and is most often associated to massive spread of MDR/XDR TB, although these epidemiological or pathological properties have not been confirmed for all strains and in all geographic settings. In this paper, to gain new insights into the biogeographical heterogeneity of the Beijing family, we investigated a global sample of Beijing strains (22% from Italian-born, 78% from foreign-born patients) by determining large sequence polymorphism of regions RD105, RD181, RD150 and RD142, single nucleotide polymorphism of putative DNA repair genes mutT4 and mutT2 and MIRU-VNTR profiles based on 11 discriminative loci. We found that, although our sample of Beijing strains showed a considerable genomic heterogeneity, yielding both ancient and recent phylogenetic strains, the prevalent successful Beijing subsets were characterized by deletions of RD105 and RD181 and by one nucleotide substitution in one or both mutT genes. MIRU-VNTR analysis revealed 47 unique patterns and 9 clusters including a total of 33 isolates (41% of total isolates); the relatively high proportion of Italian-born Beijing TB patients, often occurring in mixed clusters, supports the possibility of an ongoing cross-transmission of the Beijing genotype to autochthonous population. High rates of extra-pulmonary localization and drug-resistance, particularly MDR, frequently reported for Beijing strains in other settings, were not observed in our survey. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Repetition or Reconfiguration

    DEFF Research Database (Denmark)

    Andersen, Kristina Vaarst

    , the cognitive quality of knowledge held by individual professionals is the key microfoundation for project level performance. This paper empirically tests effects of project participants with and without knowledge diversity for project level performance for projects aiming for varying degrees of repetition...... and reconfiguration. The results indicate that project performance benefits form contributions from individuals holding diverse knowledge only when projects aim for high differentiation levels. This positive association is not just moderated, it may even be reversed in the case of professionals participating in low...

  10. MIMICRY, DIFFERENCE AND REPETITION

    Directory of Open Access Journals (Sweden)

    Marcelo Mendes de Souza

    2008-07-01

    Full Text Available This article addresses Homi K. Bhabha’s concept of mimicry in a broader context, other than that of cultural studies and post-colonial studies, bringing together other concepts, such as that of Gilles Deleuze in Difference and repetition, among other texts, and other names, such as Silviano Santiago, Jorge Luís Borges, Franz Kafka and Giorgio Agamben. As a partial conclusion, the article intends to oppose Bhabha’s freudian-marxist view to Five propositions on Psychoanalysis (1973, Gilles Deleuze’s text about Psychoanalysis published right after his book The Anti-Oedipus.

  11. Emotional response to musical repetition.

    Science.gov (United States)

    Livingstone, Steven R; Palmer, Caroline; Schubert, Emery

    2012-06-01

    Two experiments examined the effects of repetition on listeners' emotional response to music. Listeners heard recordings of orchestral music that contained a large section repeated twice. The music had a symmetric phrase structure (same-length phrases) in Experiment 1 and an asymmetric phrase structure (different-length phrases) in Experiment 2, hypothesized to alter the predictability of sensitivity to musical repetition. Continuous measures of arousal and valence were compared across music that contained identical repetition, variation (related), or contrasting (unrelated) structure. Listeners' emotional arousal ratings differed most for contrasting music, moderately for variations, and least for repeating musical segments. A computational model for the detection of repeated musical segments was applied to the listeners' emotional responses. The model detected the locations of phrase boundaries from the emotional responses better than from performed tempo or physical intensity in both experiments. These findings indicate the importance of repetition in listeners' emotional response to music and in the perceptual segmentation of musical structure.

  12. Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation.

    Directory of Open Access Journals (Sweden)

    Amanda Malvessi Cattani

    Full Text Available Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5' upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile.

  13. Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation.

    Science.gov (United States)

    Cattani, Amanda Malvessi; Siqueira, Franciele Maboni; Guedes, Rafael Lucas Muniz; Schrank, Irene Silveira

    2016-01-01

    Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5' upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile.

  14. Repetition and lag effects in movement recognition.

    Science.gov (United States)

    Hall, C R; Buckolz, E

    1982-03-01

    Whether repetition and lag improve the recognition of movement patterns was investigated. Recognition memory was tested for one repetition, two-repetitions massed, and two-repetitions distributed with movement patterns at lags of 3, 5, 7, and 13. Recognition performance was examined both immediately afterwards and following a 48 hour delay. Both repetition and lag effects failed to be demonstrated, providing some support for the claim that memory is unaffected by repetition at a constant level of processing (Craik & Lockhart, 1972). There was, as expected, a significant decrease in recognition memory following the retention interval, but this appeared unrelated to repetition or lag.

  15. Global Repetition Influences Contextual Cueing

    Science.gov (United States)

    Zang, Xuelian; Zinchenko, Artyom; Jia, Lina; Li, Hong

    2018-01-01

    Our visual system has a striking ability to improve visual search based on the learning of repeated ambient regularities, an effect named contextual cueing. Whereas most of the previous studies investigated contextual cueing effect with the same number of repeated and non-repeated search displays per block, the current study focused on whether a global repetition frequency formed by different presentation ratios between the repeated and non-repeated configurations influence contextual cueing effect. Specifically, the number of repeated and non-repeated displays presented in each block was manipulated: 12:12, 20:4, 4:20, and 4:4 in Experiments 1–4, respectively. The results revealed a significant contextual cueing effect when the global repetition frequency is high (≥1:1 ratio) in Experiments 1, 2, and 4, given that processing of repeated displays was expedited relative to non-repeated displays. Nevertheless, the contextual cueing effect reduced to a non-significant level when the repetition frequency reduced to 4:20 in Experiment 3. These results suggested that the presentation frequency of repeated relative to the non-repeated displays could influence the strength of contextual cueing. In other words, global repetition statistics could be a crucial factor to mediate contextual cueing effect. PMID:29636716

  16. Repetitive elements in parasitic protozoa

    Directory of Open Access Journals (Sweden)

    Clayton Christine

    2010-05-01

    Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

  17. The repetition effect in building and construction works

    DEFF Research Database (Denmark)

    Gottlieb, Stefan Christoffer; Haugbølle, Kim

    are then applied on the Public Transport Authorities' main account structure of units and costs, and a method for assessing the possibilities of achieving effects of repetition for each account is described. Finally, the report summarises the core conditions necessary to take into consideration in relation......This report summarises the results from the work undertaken for the Public Transport Authority on the effect of learning and repetition in building and construction works. The results are applied by the Public Transport Authority in a new budgeting model, while the agency investigates...

  18. Pull-production in repetitive remanufacturing

    Energy Technology Data Exchange (ETDEWEB)

    McCaskey, D.W. Jr.

    1992-09-01

    In the past, production activity control practices in most repetitive remanufacturing facilities resembled those used in intermittent production operations. These operations were characterized by large amounts of work-in-process (WIP), frequent work stoppages due to part shortages, excessive overtime, low product velocity, informal scheduling between dependent operations, low employee and management moral, and a lot of wasted time, material, labor, and space. Improvement in production activity control (PAC) methods for repetitive remanufactures has been hampered by uncertainty in: supply of incoming assets, configuration of assets, process times to refurbish assets, and yields in reclamation processes. collectively these uncertainties make shop floor operations seem uncontrollable. However, one United States Army depot has taken on the challenge. Through management supported, cross-functional teams, the Tooele Army Depot has designed and implemented pull-production systems for two of its major products, with several others to follow. This article presents a generalized version of Tooele`s pull-production system and highlights design characteristics which are specific to remanufacturing applications.

  19. Pull-production in repetitive remanufacturing

    Energy Technology Data Exchange (ETDEWEB)

    McCaskey, D.W. Jr.

    1992-09-01

    In the past, production activity control practices in most repetitive remanufacturing facilities resembled those used in intermittent production operations. These operations were characterized by large amounts of work-in-process (WIP), frequent work stoppages due to part shortages, excessive overtime, low product velocity, informal scheduling between dependent operations, low employee and management moral, and a lot of wasted time, material, labor, and space. Improvement in production activity control (PAC) methods for repetitive remanufactures has been hampered by uncertainty in: supply of incoming assets, configuration of assets, process times to refurbish assets, and yields in reclamation processes. collectively these uncertainties make shop floor operations seem uncontrollable. However, one United States Army depot has taken on the challenge. Through management supported, cross-functional teams, the Tooele Army Depot has designed and implemented pull-production systems for two of its major products, with several others to follow. This article presents a generalized version of Tooele's pull-production system and highlights design characteristics which are specific to remanufacturing applications.

  20. Repetition code of 15 qubits

    Science.gov (United States)

    Wootton, James R.; Loss, Daniel

    2018-05-01

    The repetition code is an important primitive for the techniques of quantum error correction. Here we implement repetition codes of at most 15 qubits on the 16 qubit ibmqx3 device. Each experiment is run for a single round of syndrome measurements, achieved using the standard quantum technique of using ancilla qubits and controlled operations. The size of the final syndrome is small enough to allow for lookup table decoding using experimentally obtained data. The results show strong evidence that the logical error rate decays exponentially with code distance, as is expected and required for the development of fault-tolerant quantum computers. The results also give insight into the nature of noise in the device.

  1. Computer-Related Repetitive Stress Injuries

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Computer-Related Repetitive Stress Injuries KidsHealth / For Parents / Computer-Related Repetitive Stress Injuries What's in this article? ...

  2. Repetitive learning control of continuous chaotic systems

    International Nuclear Information System (INIS)

    Chen Maoyin; Shang Yun; Zhou Donghua

    2004-01-01

    Combining a shift method and the repetitive learning strategy, a repetitive learning controller is proposed to stabilize unstable periodic orbits (UPOs) within chaotic attractors in the sense of least mean square. If nonlinear parts in chaotic systems satisfy Lipschitz condition, the proposed controller can be simplified into a simple proportional repetitive learning controller

  3. Haben repetitive DNA-Sequenzen biologische Funktionen?

    Science.gov (United States)

    John, Maliyakal E.; Knöchel, Walter

    1983-05-01

    By DNA reassociation kinetics it is known that the eucaryotic genome consists of non-repetitive DNA, middle-repetitive DNA and highly repetitive DNA. Whereas the majority of protein-coding genes is located on non-repetitive DNA, repetitive DNA forms a constitutive part of eucaryotic DNA and its amount in most cases equals or even substantially exceeds that of non-repetitive DNA. During the past years a large body of data on repetitive DNA has accumulated and these have prompted speculations ranging from specific roles in the regulation of gene expression to that of a selfish entity with inconsequential functions. The following article summarizes recent findings on structural, transcriptional and evolutionary aspects and, although by no means being proven, some possible biological functions are discussed.

  4. Repetitively pulsed material testing facility

    International Nuclear Information System (INIS)

    Zucker, O.; Bostick, W.; Gullickson, R; Long, J.; Luce, J.; Sahlin, H.

    1975-01-01

    A continuously operated, 1 pps, dense-plasma-focus device capable of delivering a minimum of 10 15 neutrons per pulse for material testing purposes is described. Moderate scaling from existing results is sufficient to provide 2 x 10 13 n/cm 2 .s to a suitable target. The average power consumption, which has become a major issue as a result of the energy crisis, is analyzed with respect to other plasma devices and is shown to be highly favorable. A novel approach to the capacitor bank and switch design allowing repetitive operation is discussed. (U.S.)

  5. Repetitively pulsed material testing facility

    International Nuclear Information System (INIS)

    Zucker, O.; Bostick, W.; Gullickson, R.; Long, J.; Luce, J.; Sahlin, H.

    1975-01-01

    A continuously operated, 1 pps, dense-plasma-focus device capable of delivering a minimum of 10 15 neutrons per pulse for material testing purposes is described. Moderate scaling from existing results is sufficient to provide 2 x 10 13 n/cm 2 . s to a suitable target. The average power consumption, which has become a major issue as a result of the energy crisis, is analyzed with respect to other plasma devices and is shown to be highly favorable. A novel approach to the capacitor bank and switch design allowing repetitive operation is discussed

  6. Mycobacterium tuberculosis Isolates from Single Outpatient Clinic in Panama City Exhibit Wide Genetic Diversity

    Science.gov (United States)

    Sambrano, Dilcia; Correa, Ricardo; Almengor, Pedro; Domínguez, Amada; Vega, Silvio; Goodridge, Amador

    2014-01-01

    Understanding Mycobacterium tuberculosis biodiversity and transmission is significant for tuberculosis control. This short report aimed to determine the genetic diversity of M. tuberculosis isolates from an outpatient clinic in Panama City. A total of 62 M. tuberculosis isolates were genotyped by 12 loci mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) and Spoligotyping. Forty-five (72.6%) of the isolates showed unique MIRU-VNTR genotypes, and 13 (21%) of the isolates were grouped into four clusters. Four isolates showed polyclonal MIRU-VNTR genotypes. The MIRU-VNTR Hunter-Gaston discriminatory index reached 0.988. The Spoligotyping analysis revealed 16 M. tuberculosis families, including Latin American-Mediterranean, Harlem, and Beijing. These findings suggest a wide genetic diversity of M. tuberculosis isolates at one outpatient clinic. A detailed molecular epidemiology survey is now warranted, especially following second massive immigration for local Panama Canal expansion activities. PMID:24865686

  7. Repetitive trauma and nerve compression.

    Science.gov (United States)

    Carragee, E J; Hentz, V R

    1988-01-01

    Repetitive movement of the upper extremity, whether recreational or occupational, may result in various neuropathies, the prototype of which is the median nerve neuropathic in the carpal canal. The pathophysiology of this process is incompletely understood but likely involves both mechanical and ischemic features. Experimentally increased pressures within the carpal canal produced reproducible progressive neuropathy. Changes in vibratory (threshold-type) sensibility appears to be more sensitive than two-point (innervation density-type) sensibility. The specific occupational etiologies of carpal neuropathy are obscured by methodologic and sociological difficulties, but clearly some occupations have high incidences of CTS. History and physical examination are usually sufficient for the diagnosis, but diagnostic assistance when required is available through electrophysiological testing, CT scanning, and possibly MRI. Each of these tests has limitations in both sensitivity and specificity. Treatment by usual conservative means should be combined with rest from possible provocative activities. Surgical release of the carpal canal is helpful in patients failing conservative therapy. Occupational modifications are important in both treatment and prevention of median neuropathy due to repetitive trauma.

  8. Repetitively pulsed power for meat pasteurization

    International Nuclear Information System (INIS)

    Patterson, E.L.; Kaye, R.J.; Neau, E.L.

    1994-01-01

    Electronic pasteurization of meat offers the potential for drastically reducing the incidence of food poisoning caused by biological pathogens accidentally introduced into meat products. Previous work has shown that γ-rays are an effective method of destroying E. coli 0157:H7, Salmonella, C. jejuni, L. monocytogenes, Listeria, and S. aureus bacteria types. The concern with the use of γ-rays is that radioactive material must be used in the pasteurization process that can lead to some market resistance and activist pressure on the meat industry. The use of accelerator generated high average power electron beams, at energies less than 10 MeV, or X-rays, with energies below 5 MeV, have been approved by the FDA for use in pasteurizing foods. Accelerator produced electronic pasteurization has the advantage that no radioactive material inventory is required. Electronic pasteurization has the additional benefit that it removes bacterial pathogens on the meat surface as well as within the volume of the meat product. High average power, repetitively-pulsed, broad-area electron beam sources being developed in the RHEPP program are suitable for large scale meat treatment in packing plant environments. RHEPP-II, which operates at 2.5 MeV and 25 kA at pulse repetition frequencies up to 120 Hz has adequate electron energy to penetrate hamburger patties which comprise about half of the beef consumption in the United States. Ground beef also has the highest potential for contamination since considerable processing is required in its production. A meat pasteurization facility using this size of accelerator source should be capable of treating 10 6 pounds of hamburger patties per hour to a dose of up to 3 kGy (300 kilorads). The RHEPP modular accelerator technology can easily be modified for other production rates and types of products

  9. A Nonword Repetition Task for Speakers with Misarticulations: The Syllable Repetition Task (SRT)

    Science.gov (United States)

    Shriberg, Lawrence D.; Lohmeier, Heather L.; Campbell, Thomas F.; Dollaghan, Christine A.; Green, Jordan R.; Moore, Christopher A.

    2009-01-01

    Purpose: Conceptual and methodological confounds occur when non(sense) word repetition tasks are administered to speakers who do not have the target speech sounds in their phonetic inventories or who habitually misarticulate targeted speech sounds. In this article, the authors (a) describe a nonword repetition task, the Syllable Repetition Task…

  10. The Developmental Trajectory of Nonword Repetition

    Science.gov (United States)

    Chiat, Shula

    2006-01-01

    In line with the original presentation of nonword repetition as a measure of phonological short-term memory (Gathercole & Baddeley, 1989), the theoretical account Gathercole (2006) puts forward in her Keynote Article focuses on phonological storage as the key capacity common to nonword repetition and vocabulary acquisition. However, evidence that…

  11. Grade Repetition in Queensland State Prep Classes

    Science.gov (United States)

    Anderson, Robyn

    2012-01-01

    The current study considers grade repetition rates in the early years of schooling in Queensland state schools with specific focus on the pre-schooling year, Prep. In particular, it provides empirical evidence of grade repetition in Queensland state schools along with groups of students who are more often repeated. At the same time, much of the…

  12. REPETITIVE STRENGTH AMONG STUDENTS OF AGE 14

    Directory of Open Access Journals (Sweden)

    Besim Halilaj

    2014-06-01

    Full Text Available The study involved 82 male students of the primary school “Qamil Ilazi” in Kaçanik-Kosovo.Four movement tests, which test the repetitive strength, were conducted: 1. Pull-up, 2. Sit-Up, 3. Back extension, 4. Push-up.The main goal of this study was to verify the actual motor status, respectively the component of the repetitive strength among students of age 14 of masculine gender. In addition to verifying the actual motor status, another objective was to verify the relationship between the variables employed.Basic statistical parameters show a distribution which is not significantly different from the normal distribution, yielded highly correlative values among the repetitive strength tests. Space factorization resulted in extracting two latent squares defined as repetitive strength of arms factor, and repetitive strength of body factor.

  13. Subjective duration distortions mirror neural repetition suppression.

    Science.gov (United States)

    Pariyadath, Vani; Eagleman, David M

    2012-01-01

    Subjective duration is strongly influenced by repetition and novelty, such that an oddball stimulus in a stream of repeated stimuli appears to last longer in duration in comparison. We hypothesize that this duration illusion, called the temporal oddball effect, is a result of the difference in expectation between the oddball and the repeated stimuli. Specifically, we conjecture that the repeated stimuli contract in duration as a result of increased predictability; these duration contractions, we suggest, result from decreased neural response amplitude with repetition, known as repetition suppression. Participants viewed trials consisting of lines presented at a particular orientation (standard stimuli) followed by a line presented at a different orientation (oddball stimulus). We found that the size of the oddball effect correlates with the number of repetitions of the standard stimulus as well as the amount of deviance from the oddball stimulus; both of these results are consistent with a repetition suppression hypothesis. Further, we find that the temporal oddball effect is sensitive to experimental context--that is, the size of the oddball effect for a particular experimental trial is influenced by the range of duration distortions seen in preceding trials. Our data suggest that the repetition-related duration contractions causing the oddball effect are a result of neural repetition suppression. More generally, subjective duration may reflect the prediction error associated with a stimulus and, consequently, the efficiency of encoding that stimulus. Additionally, we emphasize that experimental context effects need to be taken into consideration when designing duration-related tasks.

  14. Repetitive Bibliographical Information in Relational Databases.

    Science.gov (United States)

    Brooks, Terrence A.

    1988-01-01

    Proposes a solution to the problem of loading repetitive bibliographic information in a microcomputer-based relational database management system. The alternative design described is based on a representational redundancy design and normalization theory. (12 references) (Author/CLB)

  15. High-resolution minisatellite-based typing as a portable approach to global analysis of Mycobacterium tuberculosis molecular epidemiology

    Science.gov (United States)

    Mazars, Edith; Lesjean, Sarah; Banuls, Anne-Laure; Gilbert, Michèle; Vincent, Véronique; Gicquel, Brigitte; Tibayrenc, Michel; Locht, Camille; Supply, Philip

    2001-01-01

    The worldwide threat of tuberculosis to human health emphasizes the need to develop novel approaches to a global epidemiological surveillance. The current standard for Mycobacterium tuberculosis typing based on IS6110 restriction fragment length polymorphism (RFLP) suffers from the difficulty of comparing data between independent laboratories. Here, we propose a high-resolution typing method based on variable number tandem repeats (VNTRs) of genetic elements named mycobacterial interspersed repetitive units (MIRUs) in 12 human minisatellite-like regions of the M. tuberculosis genome. MIRU-VNTR profiles of 72 different M. tuberculosis isolates were established by PCR analysis of all 12 loci. From 2 to 8 MIRU-VNTR alleles were identified in the 12 regions in these strains, which corresponds to a potential of over 16 million different combinations, yielding a resolution power close to that of IS6110-RFLP. All epidemiologically related isolates tested were perfectly clustered by MIRU-VNTR typing, indicating that the stability of these MIRU-VNTRs is adequate to track outbreak episodes. The correlation between genetic relationships inferred from MIRU-VNTR and IS6110-RFLP typing was highly significant. Compared with IS6110-RFLP, high-resolution MIRU-VNTR typing has the considerable advantages of being fast, appropriate for all M. tuberculosis isolates, including strains that have a few IS6110 copies, and permitting easy and rapid comparison of results from independent laboratories. This typing method opens the way to the construction of digital global databases for molecular epidemiology studies of M. tuberculosis. PMID:11172048

  16. Document retrieval on repetitive string collections.

    Science.gov (United States)

    Gagie, Travis; Hartikainen, Aleksi; Karhu, Kalle; Kärkkäinen, Juha; Navarro, Gonzalo; Puglisi, Simon J; Sirén, Jouni

    2017-01-01

    Most of the fastest-growing string collections today are repetitive, that is, most of the constituent documents are similar to many others. As these collections keep growing, a key approach to handling them is to exploit their repetitiveness, which can reduce their space usage by orders of magnitude. We study the problem of indexing repetitive string collections in order to perform efficient document retrieval operations on them. Document retrieval problems are routinely solved by search engines on large natural language collections, but the techniques are less developed on generic string collections. The case of repetitive string collections is even less understood, and there are very few existing solutions. We develop two novel ideas, interleaved LCPs and precomputed document lists , that yield highly compressed indexes solving the problem of document listing (find all the documents where a string appears), top- k document retrieval (find the k documents where a string appears most often), and document counting (count the number of documents where a string appears). We also show that a classical data structure supporting the latter query becomes highly compressible on repetitive data. Finally, we show how the tools we developed can be combined to solve ranked conjunctive and disjunctive multi-term queries under the simple [Formula: see text] model of relevance. We thoroughly evaluate the resulting techniques in various real-life repetitiveness scenarios, and recommend the best choices for each case.

  17. Molecular characterization of Mycobacterium tuberculosis isolates from Tanga, Tanzania: First insight of MIRU-VNTR and microarray-based spoligotyping in a high burden country.

    Science.gov (United States)

    Hoza, Abubakar S; Mfinanga, Sayoki G; Moser, Irmgard; König, Brigitte

    2016-05-01

    Molecular typing of Mycobacterium tuberculosis(MTB) has greatly enhanced the understanding of the population structure of MTB isolates and epidemiology of tuberculosis (TB). To characterize prevalent genotypes of MTB, microarrays‑based spoligotyping and mycobacterial interspersed repetitive unit‑variable number of tandem repeats (MIRU‑VNTR) were applied on 80 isolates collected from primary health care facilities in Tanga, North‑eastern Tanzania. A total of 18 distinct spoligotypes were identified. The lineages by order of their predominance were EAI and CAS families (26.25%, 21 isolates each), LAM family and T super‑family (10%, 8 isolates each), MANU family (3.75%, 3 isolates), Beijing family (2.5%, 2 isolates) and S family (1.25%, 1 isolate). Overall, sixteen (20%) strains could not be allocated to any lineage according to the SITVIT_WEB database. The allelic diversity (h) for specific MIRU‑VNTR loci showed a considerable variation ranging from 0.826 of VNTR locus 3192 to 0.141 of VNTR locus 2059. The allelic diversity for 11 loci (VNTR 3192, 2996, 2165, 960, 4052, 424, 4156, 2531, 1644, 802 and 3690) exceeded 0.6, indicating highly discriminatory power. Seven loci (VNTR 2163b, 2401, 1955, 577, 4348, 2687 and 580) showed moderate discrimination (0.3 ≤ h ≥ 0.6), and three loci (VNTR3007, 154 and 2059) were less polymorphic. The present study suggests that the TB cases in Tanga might be caused by a diverse array of MTB strain families that may be indicative of a cosmopolitan population with frequent migration and travel. Microarray‑based spoligotyping and MIRU‑VNTR could be reliable tools in detecting different MTB genotypes in high burden settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Molecular discrimination of Mycobacterium bovis in São Paulo, Brazil.

    Science.gov (United States)

    Rocha, Vivianne Cambuí Figueiredo; de Figueiredo, Salomão Cambuí; Rosales, Cesar Alejandro Rodriguez; de Hildebrand e Grisi Filho, José Henrique; Keid, Lara Borges; Soares, Rodrigo Martins; Ferreira Neto, José Soares

    2013-01-01

    Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex, is the most common agent of cattle tuberculosis, a zoonosis that causes losses in meat and milk production in several countries. In order to support epidemiological studies aimed at controlling the disease, several methods for molecular discrimination of M. bovis isolates have recently been developed. The most frequently used are spacer oligonucleotide typing (spoligotyping), mycobacterial interspersed repetitive units (MIRU), and exact tandem repeat (ETR), but they all have different discriminatory power. In the present study, allelic diversity was calculated for each MIRU and ETR locus, and the Hunter-Gaston discriminatory index (HGI) was calculated for spoligotyping, 10 MIRUs, and 3 ETRs, in 116 isolates of M. bovis obtained from cattle. The analysis of allelic diversity indicated that MIRUs 16, 26, and 27, and ETRs A, B, and C, showed the greatest diversity between the assayed loci. The HGIs for each of the techniques were: spoligotyping=0.738381; MIRU=0.829835; and ETR=0.825337. The associations of the methods' improved discriminatory power were: spoligotyping+MIRU=0.930585; spoligotyping+ETR=0.931034; and MIRU+ETR=0.953373. The greatest discriminatory power was obtained when the three techniques were associated (HGI=0.98051). Considering the analyses of the present study, spoligotyping should be the first method to be used because it differentiates M. bovis from the other members of the Mycobacterium tuberculosis complex. As the associations of MIRU and ETR with spoligotyping resulted in nearly identical HGIs, ETR seems to be the best choice after spoligotyping, because it is faster and more economical than MIRU. Finally, MIRU should be the last method used. In spite of this finding, the choice of the method used should be based on the discriminatory power necessary for the objective at hand.

  19. Subjective duration distortions mirror neural repetition suppression.

    Directory of Open Access Journals (Sweden)

    Vani Pariyadath

    Full Text Available Subjective duration is strongly influenced by repetition and novelty, such that an oddball stimulus in a stream of repeated stimuli appears to last longer in duration in comparison. We hypothesize that this duration illusion, called the temporal oddball effect, is a result of the difference in expectation between the oddball and the repeated stimuli. Specifically, we conjecture that the repeated stimuli contract in duration as a result of increased predictability; these duration contractions, we suggest, result from decreased neural response amplitude with repetition, known as repetition suppression.Participants viewed trials consisting of lines presented at a particular orientation (standard stimuli followed by a line presented at a different orientation (oddball stimulus. We found that the size of the oddball effect correlates with the number of repetitions of the standard stimulus as well as the amount of deviance from the oddball stimulus; both of these results are consistent with a repetition suppression hypothesis. Further, we find that the temporal oddball effect is sensitive to experimental context--that is, the size of the oddball effect for a particular experimental trial is influenced by the range of duration distortions seen in preceding trials.Our data suggest that the repetition-related duration contractions causing the oddball effect are a result of neural repetition suppression. More generally, subjective duration may reflect the prediction error associated with a stimulus and, consequently, the efficiency of encoding that stimulus. Additionally, we emphasize that experimental context effects need to be taken into consideration when designing duration-related tasks.

  20. Storytelling and Repetitive Narratives for Design Empathy

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Judice, Andrea; Soini, Katja

    2007-01-01

    study. In this paper, we show how we attained an empathic understanding through storytelling and aroused empathy to others using repetitive narratives in an experimental presentation bringing forth factual, reflective and experiential aspects of the user information. Taking as a starting point our...

  1. Universal data compression and repetition times

    NARCIS (Netherlands)

    Willems, Frans M J

    1989-01-01

    A new universal data compression algorithm is described. This algorithm encodes L source symbols at a time. For the class of binary stationary sources, its rate does not exceed [formula omitted] [formula omitted] bits per source symbol. In our analysis, a property of repetition times turns out to be

  2. Matriculation Research Report: Course Repetition Data & Analysis.

    Science.gov (United States)

    Gerda, Joe

    Due to concerns that its policy on class repetition was not promoting student success, California's College of the Canyons (CoC) undertook a project to analyze student course-taking patterns and make recommendations to modify the policy. Existing college policy did not follow Section 58161 of the State Educational Code that allows colleges to…

  3. Reducing Repetitive Speech: Effects of Strategy Instruction.

    Science.gov (United States)

    Dipipi, Caroline M.; Jitendra, Asha K.; Miller, Judith A.

    2001-01-01

    This article describes an intervention with an 18-year-old young woman with mild mental retardation and a seizure disorder, which focused on her repetitive echolalic verbalizations. The intervention included time delay, differential reinforcement of other behaviors, and self-monitoring. Overall, the intervention was successful in facilitating…

  4. Neurobehavioural Correlates of Abnormal Repetitive Behaviour

    Directory of Open Access Journals (Sweden)

    R. A. Ford

    1991-01-01

    Full Text Available Conditions in which echolalia and echopraxia occur are reviewed, followed by an attempt to elicit possible mechanisms of these phenomena. A brief description of stereotypical and perseverative behaviour and obsessional phenomena is given. It is suggested that abnormal repetitive behaviour may occur partly as a result of central dopaminergic dysfunction.

  5. Verbal Repetitions and Echolalia in Alzheimer's Discourse

    Science.gov (United States)

    Da Cruz, Fernanda Miranda

    2010-01-01

    This article reports on an investigation of echolalic repetition in Alzheimer's disease (AD). A qualitative analysis of data from spontaneous conversations with MHI, a woman with AD, is presented. The data come from the DALI Corpus, a corpus of spontaneous conversations involving subjects with AD. This study argues that echolalic effects can be…

  6. Bystanders' Reactions to Witnessing Repetitive Abuse Experiences

    Science.gov (United States)

    Janson, Gregory R.; Carney, JoLynn V.; Hazler, Richard J.; Oh, Insoo

    2009-01-01

    The Impact of Event Scale-Revised (D. S. Weiss & C. R. Marmar, 1997) was used to obtain self-reported trauma levels from 587 young adults recalling childhood or adolescence experiences as witnesses to common forms of repetitive abuse defined as bullying. Mean participant scores were in a range suggesting potential need for clinical assessment…

  7. Prediction of the Maximum Number of Repetitions and Repetitions in Reserve From Barbell Velocity.

    Science.gov (United States)

    García-Ramos, Amador; Torrejón, Alejandro; Feriche, Belén; Morales-Artacho, Antonio J; Pérez-Castilla, Alejandro; Padial, Paulino; Haff, Guy Gregory

    2018-03-01

    To provide 2 general equations to estimate the maximum possible number of repetitions (XRM) from the mean velocity (MV) of the barbell and the MV associated with a given number of repetitions in reserve, as well as to determine the between-sessions reliability of the MV associated with each XRM. After determination of the bench-press 1-repetition maximum (1RM; 1.15 ± 0.21 kg/kg body mass), 21 men (age 23.0 ± 2.7 y, body mass 72.7 ± 8.3 kg, body height 1.77 ± 0.07 m) completed 4 sets of as many repetitions as possible against relative loads of 60%1RM, 70%1RM, 80%1RM, and 90%1RM over 2 separate sessions. The different loads were tested in a randomized order with 10 min of rest between them. All repetitions were performed at the maximum intended velocity. Both the general equation to predict the XRM from the fastest MV of the set (CV = 15.8-18.5%) and the general equation to predict MV associated with a given number of repetitions in reserve (CV = 14.6-28.8%) failed to provide data with acceptable between-subjects variability. However, a strong relationship (median r 2  = .984) and acceptable reliability (CV  .85) were observed between the fastest MV of the set and the XRM when considering individual data. These results indicate that generalized group equations are not acceptable methods for estimating the XRM-MV relationship or the number of repetitions in reserve. When attempting to estimate the XRM-MV relationship, one must use individualized relationships to objectively estimate the exact number of repetitions that can be performed in a training set.

  8. If you negate, you may forget: negated repetitions impair memory compared with affirmative repetitions.

    Science.gov (United States)

    Mayo, Ruth; Schul, Yaacov; Rosenthal, Meytal

    2014-08-01

    One of the most robust laws of memory is that repeated activation improves memory. Our study shows that the nature of repetition matters. Specifically, although both negated repetition and affirmative repetition improve memory compared with no repetition, negated repetition hinders memory compared with affirmative repetition. After showing participants different entities, we asked them about features of these entities, leading to either "yes" or "no" responses. Our findings show that correctly negating an incorrect feature of an entity elicits an active forgetting effect compared with correctly affirming its true features. For example, after seeing someone drink a glass of white wine, answering "no" to "was it red wine?" may lead one to greater memory loss of the individual drinking wine at all compared with answering "yes" to "was it white wine?" We find this negation-induced forgetting effect in 4 experiments that differ in (a) the meaning given for the negation, (b) the type of stimuli (visual or verbal), and (c) the memory measure (recognition or free recall). We discuss possible underlying mechanisms and offer theoretical and applied implications of the negation-induced forgetting effect in relation to other known inhibition effects. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  9. High power, repetitive stacked Blumlein pulse generators

    Energy Technology Data Exchange (ETDEWEB)

    Davanloo, F; Borovina, D L; Korioth, J L; Krause, R K; Collins, C B [Univ. of Texas at Dallas, Richardson, TX (United States). Center for Quantum Electronics; Agee, F J [US Air Force Phillips Lab., Kirtland AFB, NM (United States); Kingsley, L E [US Army CECOM, Ft. Monmouth, NJ (United States)

    1997-12-31

    The repetitive stacked Blumlein pulse power generators developed at the University of Texas at Dallas consist of several triaxial Blumleins stacked in series at one end. The lines are charged in parallel and synchronously commuted with a single switch at the other end. In this way, relatively low charging voltages are multiplied to give a high discharge voltage across an arbitrary load. Extensive characterization of these novel pulsers have been performed over the past few years. Results indicate that they are capable of producing high power waveforms with rise times and repetition rates in the range of 0.5-50 ns and 1-300 Hz, respectively, using a conventional thyratron, spark gap, or photoconductive switch. The progress in the development and use of stacked Blumlein pulse generators is reviewed. The technology and the characteristics of these novel pulsers driving flash x-ray diodes are discussed. (author). 4 figs., 5 refs.

  10. A repetitive elements perspective in Polycomb epigenetics.

    Directory of Open Access Journals (Sweden)

    Valentina eCasa

    2012-10-01

    Full Text Available Repetitive elements comprise over two-thirds of the human genome. For a long time, these elements have received little attention since they were considered non functional. On the contrary, recent evidence indicates that they play central roles in genome integrity, gene expression and disease. Indeed, repeats display meiotic instability associated with disease and are located within common fragile sites, which are hotspots of chromosome rearrangements in tumors. Moreover, a variety of diseases have been associated with aberrant transcription of repetitive elements. Overall this indicates that appropriate regulation of repetitive elements’ activity is fundamental.Polycomb group (PcG proteins are epigenetic regulators that are essential for the normal development of multicellular organisms. Mammalian PcG proteins are involved in fundamental processes, such as cellular memory, cell proliferation, genomic imprinting, X-inactivation, and cancer development. PcG proteins can convey their activity through long-distance interactions also on different chromosomes. This indicates that the 3D organization of PcG proteins contributes significantly to their function. However, it is still unclear how these complex mechanisms are orchestrated and which role PcG proteins play in the multi-level organization of gene regulation. Intriguingly, the greatest proportion of Polycomb-mediated chromatin modifications is located in genomic repeats and it has been suggested that they could provide a binding platform for Polycomb proteins.Here, these lines of evidence are woven together to discuss how repetitive elements could contribute to chromatin organization in the 3D nuclear space.

  11. High repetition rate intense ion beam source

    International Nuclear Information System (INIS)

    Hammer, D.A.; Glidden, S.C.; Noonan, B.

    1992-01-01

    This final report describes a ≤ 150kV, 40kA, 100ns high repetition rate pulsed power system and intense ion beam source which is now in operation at Cornell University. Operation of the Magnetically-controlled Anode Plasma (MAP) ion diode at > 100Hz (burst mode for up to 10 pulse bursts) provides an initial look at repetition rate limitations of both the ion diode and beam diagnostics. The pulsed power systems are capable of ≥ 1kHz operation (up to 10 pulse bursts), but ion diode operation was limited to ∼100Hz because of diagnostic limitations. By varying MAP diode operating parameters, ion beams can be extracted at a few 10s of keV or at up to 150keV, the corresponding accelerating gap impedance ranging from about 1Ω to about 10Ω. The ability to make hundreds of test pulses per day at an average repetition rate of about 2 pulses per minute permits statistical analysis of diode operation as a function of various parameters. Most diode components have now survived more than 10 4 pulses, and the design and construction of the various pulsed power components of the MAP diode which have enabled us to reach this point are discussed. A high speed data acquisition system and companion analysis software capable of acquiring pulse data at 1ms intervals (in bursts of up to 10 pulses) and processing it in ≤ min is described

  12. Modeling repetitive motions using structured light.

    Science.gov (United States)

    Xu, Yi; Aliaga, Daniel G

    2010-01-01

    Obtaining models of dynamic 3D objects is an important part of content generation for computer graphics. Numerous methods have been extended from static scenarios to model dynamic scenes. If the states or poses of the dynamic object repeat often during a sequence (but not necessarily periodically), we call such a repetitive motion. There are many objects, such as toys, machines, and humans, undergoing repetitive motions. Our key observation is that when a motion-state repeats, we can sample the scene under the same motion state again but using a different set of parameters; thus, providing more information of each motion state. This enables robustly acquiring dense 3D information difficult for objects with repetitive motions using only simple hardware. After the motion sequence, we group temporally disjoint observations of the same motion state together and produce a smooth space-time reconstruction of the scene. Effectively, the dynamic scene modeling problem is converted to a series of static scene reconstructions, which are easier to tackle. The varying sampling parameters can be, for example, structured-light patterns, illumination directions, and viewpoints resulting in different modeling techniques. Based on this observation, we present an image-based motion-state framework and demonstrate our paradigm using either a synchronized or an unsynchronized structured-light acquisition method.

  13. Feature-based motion control for near-repetitive structures

    NARCIS (Netherlands)

    Best, de J.J.T.H.

    2011-01-01

    In many manufacturing processes, production steps are carried out on repetitive structures which consist of identical features placed in a repetitive pattern. In the production of these repetitive structures one or more consecutive steps are carried out on the features to create the final product.

  14. Lingual Kinematics during Rapid Syllable Repetition in Parkinson's Disease

    Science.gov (United States)

    Wong, Min Ney; Murdoch, Bruce E.; Whelan, Brooke-Mai

    2012-01-01

    Background: Rapid syllable repetition tasks are commonly used in the assessment of motor speech disorders. However, little is known about the articulatory kinematics during rapid syllable repetition in individuals with Parkinson's disease (PD). Aims: To investigate and compare lingual kinematics during rapid syllable repetition in dysarthric…

  15. Grade Repetition and Primary School Dropout in Uganda

    Science.gov (United States)

    Kabay, Sarah

    2016-01-01

    Research on education in low-income countries rarely focuses on grade repetition. When addressed, repetition is typically presented along with early school dropout as the "wasting" of educational resources. Simplifying grade repetition in this way often fails to recognize significant methodological concerns and also overlooks the unique…

  16. Imbalance between abstract and concrete repetitive thinking modes in schizophrenia.

    Science.gov (United States)

    Maurage, Pierre; Philippot, Pierre; Grynberg, Delphine; Leleux, Dominique; Delatte, Benoît; Mangelinckx, Camille; Belge, Jan-Baptist; Constant, Eric

    2017-10-01

    Repetitive thoughts can be divided in two modes: abstract/analytic (decontextualized and dysfunctional) and concrete/experiential (problem-focused and adaptive). They constitute a transdiagnostic process involved in many psychopathological states but have received little attention in schizophrenia, as earlier studies only indexed increased ruminations (related to dysfunctional repetitive thoughts) without jointly exploring both modes. This study explored the two repetitive thinking modes, beyond ruminations, to determine their imbalance in schizophrenia. Thirty stabilized patients with schizophrenia and 30 matched controls completed the Repetitive Response Scale and the Mini Cambridge-Exeter Repetitive Thought Scale, both measuring repetitive thinking modes. Complementary measures related to schizophrenic symptomatology, depression and anxiety were also conducted. Compared to controls, patients with schizophrenia presented an imbalance between repetitive thinking modes, with increased abstract/analytic and reduced concrete/experiential thoughts, even after controlling for comorbidities. Schizophrenia is associated with stronger dysfunctional repetitive thoughts (i.e. abstract thinking) and impaired ability to efficiently use repetitive thinking for current problem-solving (i.e. concrete thinking). This imbalance confirms the double-faced nature of repetitive thinking modes, whose influence on schizophrenia's symptomatology should be further investigated. The present results also claim for evaluating these processes in clinical settings and for rehabilitating the balance between opposite repetitive thinking modes. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Repetitive thinking, executive functioning, and depressive mood in the elderly.

    Science.gov (United States)

    Philippot, Pierre; Agrigoroaei, Stefan

    2017-11-01

    Previous findings and the depressive-executive dysfunction hypothesis suggest that the established association between executive functioning and depression is accounted for by repetitive thinking. Investigating the association between executive functioning, repetitive thinking, and depressive mood, the present study empirically tested this mediational model in a sample of older adults, while focusing on both concrete and abstract repetitive thinking. This latter distinction is important given the potential protective role of concrete repetitive thinking, in contrast to the depletive effect of abstract repetitive thinking. A sample of 43 elderly volunteers, between 75 and 95 years of age, completed tests of executive functioning (the Stroop test, the Trail Making test, and the Fluency test), and questionnaires of repetitive thinking and depression. Positive correlations were observed between abstract repetitive thinking and depressive mood, and between concrete repetitive thinking and executive functioning; a negative correlation was observed between depressive mood and executive functioning. Further, mediational analysis evidenced that the relation between executive functioning and depressive mood was mediated by abstract repetitive thinking. The present data provide, for the first time, empirical support to the depressive-executive dysfunction hypothesis: the lack of executive resources would favor a mode of abstract repetitive thinking, which in turn would deplete mood. It suggests that clinical intervention targeting depression in the elderly should take into consideration repetitive thinking modes and the executive resources needed to disengage from rumination.

  18. Transcription of repetitive DNA in Neurospora crassa

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, S K; Chaudhuri, R K

    1975-01-01

    Repeated DNA sequences of Neurospora crassa were isolated and characterized. Approximately 10 to 12 percent of N. crassa DNA sequence were repeated, of which 7.3 percent were found to be transcribed in mid-log phase of mycelial growth as measured by DNA:RNA hybridization. It is suggested that part of repetitive DNA transcripts in N. crassa were mitochondrial and part were nuclear DNA. Most of the nuclear repeated DNAs, however, code for rRNA and tRNA in N. crassa. (auth)

  19. Synergy Repetition Training versus Task Repetition Training in Acquiring New Skill.

    Science.gov (United States)

    Patel, Vrajeshri; Craig, Jamie; Schumacher, Michelle; Burns, Martin K; Florescu, Ionut; Vinjamuri, Ramana

    2017-01-01

    Traditionally, repetitive practice of a task is used to learn a new skill, exhibiting as immediately improved performance. Research suggests, however, that a more experience-based rather than exposure-based training protocol may allow for better transference of the skill to related tasks. In synergy-based motor control theory, fundamental motor skills, such as hand grasping, are represented with a synergy subspace that captures essential motor patterns. In this study, we propose that motor-skill learning through synergy-based mechanisms may provide advantages over traditional task repetition learning. A new task was designed to highlight the range of motion and dexterity of the human hand. Two separate training strategies were tested in healthy subjects: task repetition training and synergy training versus a control. All three groups showed improvements when retested on the same task. When tested on a similar, but different set of tasks, only the synergy group showed improvements in accuracy (9.27% increase) compared to the repetition (3.24% decline) and control (3.22% decline) groups. A kinematic analysis revealed that although joint angular peak velocities decreased, timing benefits stemmed from the initial feed-forward portion of the task (reaction time). Accuracy improvements may have derived from general improved coordination among the four involved fingers. These preliminary results warrant further investigation of synergy-based motor training in healthy individuals, as well as in individuals undergoing hand-based rehabilitative therapy.

  20. The role of short-term memory impairment in nonword repetition, real word repetition, and nonword decoding: A case study.

    Science.gov (United States)

    Peter, Beate

    2018-01-01

    In a companion study, adults with dyslexia and adults with a probable history of childhood apraxia of speech showed evidence of difficulty with processing sequential information during nonword repetition, multisyllabic real word repetition and nonword decoding. Results suggested that some errors arose in visual encoding during nonword reading, all levels of processing but especially short-term memory storage/retrieval during nonword repetition, and motor planning and programming during complex real word repetition. To further investigate the role of short-term memory, a participant with short-term memory impairment (MI) was recruited. MI was confirmed with poor performance during a sentence repetition and three nonword repetition tasks, all of which have a high short-term memory load, whereas typical performance was observed during tests of reading, spelling, and static verbal knowledge, all with low short-term memory loads. Experimental results show error-free performance during multisyllabic real word repetition but high counts of sequence errors, especially migrations and assimilations, during nonword repetition, supporting short-term memory as a locus of sequential processing deficit during nonword repetition. Results are also consistent with the hypothesis that during complex real word repetition, short-term memory is bypassed as the word is recognized and retrieved from long-term memory prior to producing the word.

  1. Object color affects identification and repetition priming.

    Science.gov (United States)

    Uttl, Bob; Graf, Peter; Santacruz, Pilar

    2006-10-01

    We investigated the influence of color on the identification of both non-studied and studied objects. Participants studied black and white and color photos of common objects and memory was assessed with an identification test. Consistent with our meta-analysis of prior research, we found that objects were easier to identify from color than from black and white photos. We also found substantial priming in all conditions, and study-to-test changes in an object's color reduced the magnitude of priming. Color-specific priming effects were large for color-complex objects, but minimal for color-simple objects. The pattern and magnitude of priming effects was not influenced either by the extent to which an object always appears in the same color (i.e., whether a color is symptomatic of an object) or by the object's origin (natural versus fabricated). We discuss the implications of our findings for theoretical accounts of object perception and repetition priming.

  2. PROJECT IMPLEMENTATION IN ORGANISATIONS OF REPETITIVE ACTIVITIES

    Directory of Open Access Journals (Sweden)

    Marek WIRKUS

    2015-04-01

    Full Text Available The study presents the implementation of projects in organisations that achieve business objectives through the imple-mentation of repetitive actions. Projects in these organisations are, on the one hand, treated as marginal activities, while the results of these projects have significant impact on the delivery of main processes, e.g. through the introduction of new products. Human capital and solutions in this field bear impact on the success of projects in these organisations, which is not always conducive to smooth implementation of projects. Conflict results from the nature of a project, which is a one-time and temporary process, so organisational solutions are also temporary. It influences on attitudes and com-mitment of the project contractors. The paper identifies and analyses factors which affect the success of the projects.

  3. Low-Intensity Repetitive Exercise Induced Rhabdomyolysis

    Directory of Open Access Journals (Sweden)

    Mina Tran

    2015-01-01

    Full Text Available Rhabdomyolysis is a rare condition caused by the proteins of damaged muscle cells entering the bloodstream and damaging the kidneys. Common symptoms of rhabdomyolysis are muscle pain and fatigue in conjunction with dark urine; kidney damage is a common symptom among these patients. We present a case of a 23-year-old woman who displayed myalgia in the upper extremities caused by low-intensity and high-repetition exercise. She was successfully diagnosed and treated for exertional rhabdomyolysis. This patient had no significant medical history that would induce this condition. We urge the emergency medical community to observe and monitor patients that complain of myalgia to ensure they are not suffering from rhabdomyolysis even in atypical cases.

  4. FEMA Hazard Mitigation Assistance Severe Repetitive Loss (SRL) Data

    Data.gov (United States)

    Department of Homeland Security — This dataset contains closed and obligated projects funded under the following Hazard Mitigation Assistance (HMA) grant programs: Severe Repetitive Loss (SRL). The...

  5. FEMA Hazard Mitigation Assistance Repetitive Flood Claims (RFC) Data

    Data.gov (United States)

    Department of Homeland Security — This dataset contains closed and obligated projects funded under the following Hazard Mitigation Assistance (HMA) grant programs: Repetitive Flood Claims (RFC). The...

  6. MAXIMUM NUMBER OF REPETITIONS, TOTAL WEIGHT LIFTED AND NEUROMUSCULAR FATIGUE IN INDIVIDUALS WITH DIFFERENT TRAINING BACKGROUNDS

    Directory of Open Access Journals (Sweden)

    Valeria Panissa

    2013-04-01

    Full Text Available The aim of this study was to evaluate the performance, as well as neuromuscular activity, in a strength task in subjects with different training backgrounds. Participants (n = 26 were divided into three groups according to their training backgrounds (aerobic, strength or mixed and submitted to three sessions: (1 determination of the maximum oxygen uptake during the incremental treadmill test to exhaustion and familiarization of the evaluation of maximum strength (1RM for the half squat; (2 1RM determination; and (3 strength exercise, four sets at 80�0of the 1RM, in which the maximum number of repetitions (MNR, the total weight lifted (TWL, the root mean square (RMS and median frequency (MF of the electromyographic (EMG activity for the second and last repetition were computed. There was an effect of group for MNR, with the aerobic group performing a higher MNR compared to the strength group (P = 0.045, and an effect on MF with a higher value in the second repetition than in the last repetition (P = 0.016. These results demonstrated that individuals with better aerobic fitness were more fatigue resistant than strength trained individuals. The absence of differences in EMG signals indicates that individuals with different training backgrounds have a similar pattern of motor unit recruitment during a resistance exercise performed until failure, and that the greater capacity to perform the MNR probably can be explained by peripheral adaptations.

  7. The Golden Ratio of Gait Harmony: Repetitive Proportions of Repetitive Gait Phases

    Directory of Open Access Journals (Sweden)

    Marco Iosa

    2013-01-01

    Full Text Available In nature, many physical and biological systems have structures showing harmonic properties. Some of them were found related to the irrational number known as the golden ratio that has important symmetric and harmonic properties. In this study, the spatiotemporal gait parameters of 25 healthy subjects were analyzed using a stereophotogrammetric system with 25 retroreflective markers located on their skin. The proportions of gait phases were compared with , the value of which is about 1.6180. The ratio between the entire gait cycle and stance phase resulted in 1.620 ± 0.058, that between stance and the swing phase was 1.629 ± 0.173, and that between swing and the double support phase was 1.684 ± 0.357. All these ratios did not differ significantly from each other (, , repeated measure analysis of variance or from (, resp., t-tests. The repetitive gait phases of physiological walking were found in turn in repetitive proportions with each other, revealing an intrinsic harmonic structure. Harmony could be the key for facilitating the control of repetitive walking. Harmony is a powerful unifying factor between seemingly disparate fields of nature, including human gait.

  8. Photocathodes for High Repetition Rate Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Zvi, Ilan [Stony Brook Univ., NY (United States). Dept. of Physics and Astronomy. Center for Accelerator Science and Education

    2014-04-20

    This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). Below details the Principal Investigators and contact information. Each PI submits separately for a budget through his corresponding institute. The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-­conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-­antimonide cathodes (BNL – LBNL) b) Development and testing of a diamond amplifier for photocathodes (SBU -­ BNL) c) Tests of both cathodes in superconducting RF photoguns (SBU) and copper RF photoguns (LBNL) Our work made extensive use of synchrotron radiation materials science techniques, such as powder-­ and single-­crystal diffraction, x-­ray fluorescence, EXAFS and variable energy XPS. BNL and LBNL have many complementary facilities at the two light sources associated with these laboratories (NSLS and ALS, respectively); use of these will be a major thrust of our program and bring our understanding of these complex materials to a new level. In addition, CHESS at Cornell will be used to continue seamlessly throughout the NSLS dark period and

  9. Visual attention to advertising : The impact of motivation and repetition

    NARCIS (Netherlands)

    Pieters, RGM; Rosbergen, E; Hartog, M; Corfman, KP; Lynch, JG

    1996-01-01

    Using eye-tracking data, we examine the impact of motivation and repetition on visual attention to advertisements differing in argument quality. Our analyses indicate that repetition leads to an overall decrease in the amount of attention. However, while at first high motivation subjects attend to

  10. Repetitively pulsed, double discharge TEA CO/sub 2/ laser

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, D C; James, D J; Ramsden, S A

    1975-10-01

    The design and operation of a repetitively pulsed TEA CO/sub 2/ laser is described. Average powers of up to 400 W at a repetition frequency of 200 pulses/s have been obtained. The system has also been used to provide long pulses (over 20 ..mu..s) and tunable single axial mode pulses.

  11. Effects of repetition and temperature on Contingent Electrical Stimulation

    DEFF Research Database (Denmark)

    Castrillon, Eduardo E.; Zhou, Xinwen; Svensson, Peter

    ) activity associated with bruxism. Repetition of the electrical stimulus and skin surface temperature (ST) may affect the perception of CES and possibly also the inhibitory EMG effects.Objectives: To determine the effects of stimulus repetition and skin ST on the perception of CES.  Methods: Healthy...

  12. Repetition Blindness: Out of Sight or Out of Mind?

    Science.gov (United States)

    Morris, Alison L.; Harris, Catherine L.

    2004-01-01

    Does repetition blindness represent a failure of perception or of memory? In Experiment 1, participants viewed rapid serial visual presentation (RSVP) sentences. When critical words (C1 and C2) were orthographically similar, C2 was frequently omitted from serial report; however, repetition priming for C2 on a postsentence lexical decision task was…

  13. Evidence-Based Behavioral Interventions for Repetitive Behaviors in Autism

    Science.gov (United States)

    Boyd, Brian A.; McDonough, Stephen G.; Bodfish, James W.

    2012-01-01

    Restricted and repetitive behaviors (RRBs) are a core symptom of autism spectrum disorders (ASD). There has been an increased research emphasis on repetitive behaviors; however, this research primarily has focused on phenomenology and mechanisms. Thus, the knowledge base on interventions is lagging behind other areas of research. The literature…

  14. Pre-Lexical Disorders in Repetition Conduction Aphasia

    Science.gov (United States)

    Sidiropoulos, Kyriakos; de Bleser, Ria; Ackermann, Hermann; Preilowski, Bruno

    2008-01-01

    At the level of clinical speech/language evaluation, the repetition type of conduction aphasia is characterized by repetition difficulties concomitant with reduced short-term memory capacities, in the presence of fluent spontaneous speech as well as unimpaired naming and reading abilities. It is still unsettled which dysfunctions of the…

  15. Repetitive exposure: Brain and reflex measures of emotion and attention

    Science.gov (United States)

    Ferrari, Vera; Bradley, Margaret M.; Codispoti, Maurizio; Lang, Peter J.

    2010-01-01

    Effects of massed repetition on the modulation of the late positive potential elicited during affective picture viewing were investigated in two experiments. Despite a difference in the number of repetitions across studies (from 5 to 30), results were quite similar: the late positive potential continued to be enhanced when viewing emotional, compared to neutral, pictures. On the other hand, massed repetition did prompt a reduction in the late positive potential that was most pronounced for emotional pictures. Startle probe P3 amplitude generally increased with repetition, suggesting diminished attention allocation to repeated pictures. The blink reflex, however, continued to be modulated by hedonic valence, despite massive massed repetition. Taken together, the data suggest that the amplitude of the late positive potential during picture viewing reflects both motivational significance and attention allocation. PMID:20701711

  16. Repetition and Emotive Communication in Music Versus Speech

    Directory of Open Access Journals (Sweden)

    Elizabeth Hellmuth eMargulis

    2013-04-01

    Full Text Available Music and speech are often placed alongside one another as comparative cases. Their relative overlaps and disassociations have been well explored (e.g. Patel, 2010. But one key attribute distinguishing these two domains has often been overlooked: the greater preponderance of repetition in music in comparison to speech. Recent fMRI studies have shown that familiarity – achieved through repetition – is a critical component of emotional engagement with music (Pereira et al., 2011. If repetition is fundamental to emotional responses to music, and repetition is a key distinguisher between the domains of music and speech, then close examination of the phenomenon of repetition might help clarify the ways that music elicits emotion differently than speech.

  17. Transgenerational effects of environmental enrichment on repetitive motor behavior development.

    Science.gov (United States)

    Bechard, Allison R; Lewis, Mark H

    2016-07-01

    The favorable consequences of environmental enrichment (EE) on brain and behavior development are well documented. Much less is known, however, about transgenerational benefits of EE on non-enriched offspring. We explored whether transgenerational effects of EE might extend to the development of repetitive motor behaviors in deer mice. Repetitive motor behaviors are invariant patterns of movement that, across species, can be reduced by EE. We found that EE not only attenuated the development of repetitive behavior in dams, but also in their non-enriched offspring. Moreover, maternal behavior did not seem to mediate the transgenerational effect we found, although repetitive behavior was affected by reproductive experience. These data support a beneficial transgenerational effect of EE on repetitive behavior development and suggest a novel benefit of reproductive experience. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Repetitive switching for an electromagnetic rail gun

    Science.gov (United States)

    Gruden, J. M.

    1983-12-01

    Previous testing on a repetitive opening switch for inductive energy storage has proved the feasibility of the rotary switch concept. The concept consists of a rotating copper disk (rotor) with a pie-shaped insulator section and brushes which slide along each of the rotor surfaces. While on top of the copper surface, the brushes and rotor conduct current allowing the energy storage inductor to charge. When the brushes slide onto the insulator section, the current cannot pass through the rotor and is diverted into the load. This study investigates two new brush designs and a rotor modification designed to improve the current commutating capabilities of the switch. One brush design (fringe fiber) employs carbon fibers on the leading and trailing edge of the brush to increase the resistive commutating action as the switch opens and closes. The other brush design uses fingers to conduct current to the rotor surface, effectively increasing the number of brush contact points. The rotor modification was the placement of tungsten inserts at the copper-insulator interfaces.

  19. Repetitive Interrogation of 2-Level Quantum Systems

    Science.gov (United States)

    Prestage, John D.; Chung, Sang K.

    2010-01-01

    Trapped ion clocks derive information from a reference atomic transition by repetitive interrogations of the same quantum system, either a single ion or ionized gas of many millions of ions. Atomic beam frequency standards, by contrast, measure reference atomic transitions in a continuously replenished "flow through" configuration where initial ensemble atomic coherence is zero. We will describe some issues and problems that can arise when atomic state selection and preparation of the quantum atomic system is not completed, that is, optical pumping has not fully relaxed the coherence and also not fully transferred atoms to the initial state. We present a simple two-level density matrix analysis showing how frequency shifts during the state-selection process can cause frequency shifts of the measured clock transition. Such considerations are very important when a low intensity lamp light source is used for state selection, where there is relatively weak relaxation and re-pumping of ions to an initial state and much weaker 'environmental' relaxation of the atomic coherence set-up in the atomic sample.

  20. Power neodymium-glass amplifier of a repetitively pulsed laser

    Energy Technology Data Exchange (ETDEWEB)

    Vinogradov, Aleksandr V; Gaganov, V E; Garanin, Sergey G; Zhidkov, N V; Krotov, V A; Martynenko, S P; Pozdnyakov, E V; Solomatin, I I [Russian Federal Nuclear Center ' All-Russian Research Institute of Experimental Physics' , Sarov, Nizhnii Novgorod region (Russian Federation)

    2011-11-30

    A neodymium-glass diode-pumped amplifier with a zigzag laser beam propagation through the active medium was elaborated; the amplifier is intended for operation in a repetitively pulsed laser. An amplifier unit with an aperture of 20 Multiplication-Sign 25 mm and a {approx}40-cm long active medium was put to a test. The energy of pump radiation amounts to 140 J at a wavelength of 806 nm for a pump duration of 550 {mu}s. The energy parameters of the amplifier were experimentally determined: the small-signal gain per pass {approx}3.2, the linear gain {approx}0.031 cm{sup -1} with a nonuniformity of its distribution over the aperture within 15%, the stored energy of 0.16 - 0.21 J cm{sup -3}. The wavefront distortions in the zigzag laser-beam propagation through the active element of the amplifier did not exceed 0.4{lambda} ({lambda} = 0.63 {mu}m is the probing radiation wavelength).

  1. Power neodymium-glass amplifier of a repetitively pulsed laser

    International Nuclear Information System (INIS)

    Vinogradov, Aleksandr V; Gaganov, V E; Garanin, Sergey G; Zhidkov, N V; Krotov, V A; Martynenko, S P; Pozdnyakov, E V; Solomatin, I I

    2011-01-01

    A neodymium-glass diode-pumped amplifier with a zigzag laser beam propagation through the active medium was elaborated; the amplifier is intended for operation in a repetitively pulsed laser. An amplifier unit with an aperture of 20 × 25 mm and a ∼40-cm long active medium was put to a test. The energy of pump radiation amounts to 140 J at a wavelength of 806 nm for a pump duration of 550 μs. The energy parameters of the amplifier were experimentally determined: the small-signal gain per pass ∼3.2, the linear gain ∼0.031 cm -1 with a nonuniformity of its distribution over the aperture within 15%, the stored energy of 0.16 - 0.21 J cm -3 . The wavefront distortions in the zigzag laser-beam propagation through the active element of the amplifier did not exceed 0.4λ (λ = 0.63 μm is the probing radiation wavelength).

  2. RS-20 type repetitive generator with planar configuration of plasma opening switch

    Energy Technology Data Exchange (ETDEWEB)

    Agalakov, V P; Barinov, N U; Belenki, G S [Kurchatov Inst., Moscow (Russian Federation); and others

    1997-12-31

    The existing experience with the production of repetitive rate accelerators with a high peak power (in excess of 10{sup 10} W) and an average power above 50 kW makes it possible to resolve a number of physics and technology tasks which are connected with the reliability and life of the accelerator. The design and results on optimization of a simple plasma opening switch (POS) are discussed. The final design of the POS provided voltages of up to 2 MV and had a life of more than 105 pulses including 4 hours of continuous operation under 4 Hz repetition rate and wall plug power 65 kW. This unit was tested at the RS-20 type accelerator both at the Kurchatov Institute and at the Northwest Institute of Nuclear Technology in China. (author). 5 figs., 1 ref.

  3. Repetitive transcranial magnetic stimulation in psychiatry

    Directory of Open Access Journals (Sweden)

    Biswa Ranjan Mishra

    2011-01-01

    Full Text Available Repetitive transcranial magnetic stimulation (rTMS is a non-invasive and relatively painless tool that has been used to study various cognitive functions as well as to understand the brain-behavior relationship in normal individuals as well as in those with various neuropsychiatric disorders. It has also been used as a therapeutic tool in various neuropsychiatric disorders because of its ability to specifically modulate distinct brain areas. Studies have shown that repeated stimulation at low frequency produces long-lasting inhibition, which is called as long-term depression, whereas repeated high-frequency stimulation can produce excitation through long-term potentiation. This paper reviews the current status of rTMS as an investigative and therapeutic modality in various neuropsychiatric disorders. It has been used to study the cortical and subcortical functions, neural plasticity and brain mapping in normal individuals and in various neuropsychiatric disorders. rTMS has been most promising in the treatment of depression, with an overall milder adverse effect profile compared with electroconvulsive therapy. In other neuropsychiatric disorders such as schizophrenia, mania, epilepsy and substance abuse, it has been found to be useful, although further studies are required to establish therapeutic efficacy. It appears to be ineffective in the treatment of obsessive compulsive disorder. There is a paucity of studies of efficacy and safety of rTMS in pediatric and geriatric population. Although it appears safe, further research is required to optimize its efficacy and reduce the side-effects. Magnetic seizure therapy, which involves producing seizures akin to electroconvulsive therapy, appears to be of comparable efficacy in the treatment of depression with less cognitive adverse effects.

  4. Repetition-based Interactive Facade Modeling

    KAUST Repository

    AlHalawani, Sawsan

    2012-07-01

    Modeling and reconstruction of urban environments has gained researchers attention throughout the past few years. It spreads in a variety of directions across multiple disciplines such as image processing, computer graphics and computer vision as well as in architecture, geoscience and remote sensing. Having a virtual world of our real cities is very attractive in various directions such as entertainment, engineering, governments among many others. In this thesis, we address the problem of processing a single fa cade image to acquire useful information that can be utilized to manipulate the fa cade and generate variations of fa cade images which can be later used for buildings\\' texturing. Typical fa cade structures exhibit a rectilinear distribution where in windows and other elements are organized in a grid of horizontal and vertical repetitions of similar patterns. In the firt part of this thesis, we propose an efficient algorithm that exploits information obtained from a single image to identify the distribution grid of the dominant elements i.e. windows. This detection method is initially assisted with the user marking the dominant window followed by an automatic process for identifying its repeated instances which are used to define the structure grid. Given the distribution grid, we allow the user to interactively manipulate the fa cade by adding, deleting, resizing or repositioning the windows in order to generate new fa cade structures. Having the utility for the interactive fa cade is very valuable to create fa cade variations and generate new textures for building models. Ultimately, there is a wide range of interesting possibilities of interactions to be explored.

  5. Epithelial topography for repetitive tooth formation

    Directory of Open Access Journals (Sweden)

    Marcia Gaete

    2015-12-01

    Full Text Available During the formation of repetitive ectodermally derived organs such as mammary glands, lateral line and teeth, the tissue primordium iteratively initiates new structures. In the case of successional molar development, new teeth appear sequentially in the posterior region of the jaw from Sox2+ cells in association with the posterior aspect of a pre-existing tooth. The sequence of molar development is well known, however, the epithelial topography involved in the formation of a new tooth is unclear. Here, we have examined the morphology of the molar dental epithelium and its development at different stages in the mouse in vivo and in molar explants. Using regional lineage tracing we show that within the posterior tail of the first molar the primordium for the second and third molar are organized in a row, with the tail remaining in connection with the surface, where a furrow is observed. The morphology and Sox2 expression of the tail retains characteristics reminiscent of the earlier stages of tooth development, such that position along the A-P axes of the tail correlates with different temporal stages. Sox9, a stem/progenitor cell marker in other organs, is expressed mainly in the suprabasal epithelium complementary with Sox2 expression. This Sox2 and Sox9 expressing molar tail contains actively proliferating cells with mitosis following an apico-basal direction. Snail2, a transcription factor implicated in cell migration, is expressed at high levels in the tip of the molar tail while E-cadherin and laminin are decreased. In conclusion, our studies propose a model in which the epithelium of the molar tail can grow by posterior movement of epithelial cells followed by infolding and stratification involving a population of Sox2+/Sox9+ cells.

  6. Understanding communicative actions: a repetitive TMS study.

    Science.gov (United States)

    Stolk, Arjen; Noordzij, Matthijs L; Volman, Inge; Verhagen, Lennart; Overeem, Sebastiaan; van Elswijk, Gijs; Bloem, Bas; Hagoort, Peter; Toni, Ivan

    2014-02-01

    Despite the ambiguity inherent in human communication, people are remarkably efficient in establishing mutual understanding. Studying how people communicate in novel settings provides a window into the mechanisms supporting the human competence to rapidly generate and understand novel shared symbols, a fundamental property of human communication. Previous work indicates that the right posterior superior temporal sulcus (pSTS) is involved when people understand the intended meaning of novel communicative actions. Here, we set out to test whether normal functioning of this cerebral structure is required for understanding novel communicative actions using inhibitory low-frequency repetitive transcranial magnetic stimulation (rTMS). A factorial experimental design contrasted two tightly matched stimulation sites (right pSTS vs left MT+, i.e., a contiguous homotopic task-relevant region) and tasks (a communicative task vs a visual tracking task that used the same sequences of stimuli). Overall task performance was not affected by rTMS, whereas changes in task performance over time were disrupted according to TMS site and task combinations. Namely, rTMS over pSTS led to a diminished ability to improve action understanding on the basis of recent communicative history, while rTMS over MT+ perturbed improvement in visual tracking over trials. These findings qualify the contributions of the right pSTS to human communicative abilities, showing that this region might be necessary for incorporating previous knowledge, accumulated during interactions with a communicative partner, to constrain the inferential process that leads to action understanding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Opposition multiple objective symbiotic organisms search (OMOSOS for time, cost, quality and work continuity tradeoff in repetitive projects

    Directory of Open Access Journals (Sweden)

    Duc-Hoc Tran

    2018-04-01

    Full Text Available Construction managers often face with projects containing multiple units wherein activities repeat from unit to unit. Therefore effective resource management is crucial in terms of project duration, cost and quality. Accordingly, researchers have developed several models to aid planners in developing practical and near-optimal schedules for repetitive projects. Despite their undeniable benefits, such models lack the ability of pure simultaneous optimization because existing methodologies optimize the schedule with respect to a single factor, to achieve minimum duration, total cost, resource work breaks or various combinations, respectively. This study introduces a novel approach called “opposition multiple objective symbiotic organisms search” (OMOSOS for scheduling repetitive projects. The proposed algorithm used an opposition-based learning technique for population initialization and for generation jumping. Further, this study integrated a scheduling module (M1 to determine all project objectives including time, cost, quality and interruption. The proposed algorithm was implemented on two application examples in order to demonstrate its capabilities in optimizing the scheduling of repetitive construction projects. The results indicate that the OMOSOS approach is a powerful optimization technique and can assist project managers in selecting appropriate plan for project. Keywords: Symbiotic organisms search, Multi-objective analysis, Resource tradeoff, Schedules, Repetitive

  8. Spoligotyping and variable number tandem repeat analysis of Mycobacterium bovis isolates from cattle in Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Martins Parreiras

    2012-02-01

    Full Text Available We performed spoligotyping and 12-mycobacterial interspersed repetitive unit-variable number tandem repeats (MIRU-VNTRs typing to characterise Mycobacterium bovis isolates collected from tissue samples of bovines with lesions suggestive for tuberculosis during slaughter inspection procedures in abattoirs in Brazil. High-quality genotypes were obtained with both procedures for 61 isolates that were obtained from 185 bovine tissue samples and all of these isolates were identified as M. bovis by conventional identification procedures. On the basis of the spoligotyping, 53 isolates were grouped into nine clusters and the remaining eight isolates were unique types, resulting in 17 spoligotypes. The majority of the Brazilian M. bovis isolates displayed spoligotype patterns that have been previously observed in strains isolated from cattle in other countries. MIRU-VNTR typing produced 16 distinct genotypes, with 53 isolates forming eight of the groups, and individual isolates with unique VNTR profiles forming the remaining eight groups. The allelic diversity of each VNTR locus was calculated and only two of the 12-MIRU-VNTR loci presented scores with either a moderate (0.4, MIRU16 or high (0.6, MIRU26 discriminatory index (h. Both typing methods produced similar discriminatory indexes (spoligotyping h = 0.85; MIRU-VNTR h = 0.86 and the combination of the two methods increased the h value to 0.94, resulting in 29 distinct patterns. These results confirm that spoligotyping and VNTR analysis are valuable tools for studying the molecular epidemiology of M. bovis infections in Brazil.

  9. Directed PCR-free engineering of highly repetitive DNA sequences

    Directory of Open Access Journals (Sweden)

    Preissler Steffen

    2011-09-01

    Full Text Available Abstract Background Highly repetitive nucleotide sequences are commonly found in nature e.g. in telomeres, microsatellite DNA, polyadenine (poly(A tails of eukaryotic messenger RNA as well as in several inherited human disorders linked to trinucleotide repeat expansions in the genome. Therefore, studying repetitive sequences is of biological, biotechnological and medical relevance. However, cloning of such repetitive DNA sequences is challenging because specific PCR-based amplification is hampered by the lack of unique primer binding sites resulting in unspecific products. Results For the PCR-free generation of repetitive DNA sequences we used antiparallel oligonucleotides flanked by restriction sites of Type IIS endonucleases. The arrangement of recognition sites allowed for stepwise and seamless elongation of repetitive sequences. This facilitated the assembly of repetitive DNA segments and open reading frames encoding polypeptides with periodic amino acid sequences of any desired length. By this strategy we cloned a series of polyglutamine encoding sequences as well as highly repetitive polyadenine tracts. Such repetitive sequences can be used for diverse biotechnological applications. As an example, the polyglutamine sequences were expressed as His6-SUMO fusion proteins in Escherichia coli cells to study their aggregation behavior in vitro. The His6-SUMO moiety enabled affinity purification of the polyglutamine proteins, increased their solubility, and allowed controlled induction of the aggregation process. We successfully purified the fusions proteins and provide an example for their applicability in filter retardation assays. Conclusion Our seamless cloning strategy is PCR-free and allows the directed and efficient generation of highly repetitive DNA sequences of defined lengths by simple standard cloning procedures.

  10. Progress in developing repetitive pulse systems utilizing inductive energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Honig, E.M.

    1983-01-01

    High-power, fast-recovery vacuum switches were used in a new repetitive counterpulse and transfer circuit to deliver a 5-kHz pulse train with a peak power of 75 MW (at 8.6 kA) to a 1-..cap omega.. load, resulting in the first demonstration of fully controlled, high-power, high-repetition-rate operation of an inductive energy-storage and transfer system with nondestructive switches. New circuits, analytical and experimental results, and feasibility of 100-kV repetitive pulse generation are discussed. A new switching concept for railgun loads is presented.

  11. Electrical strength of vacuum gap at repetitive breakdown

    International Nuclear Information System (INIS)

    Dubinin, N.P.; Chistyakov, N.P.

    1983-01-01

    The investigation of repetitive pulse breakdown of vacuum space, which electrodes have been subjected to various treatment in vacuum and inert gas, is carried out. In case of electrode warm-up in vacuum up to 400 deg C as well as electronic heating up to 900 deg C the voltage in case of repetitive breakdown hasncreased approximately twice and in case of a through treatment, which is accomplished by a high-current glow discharge in inert gas, the maximum high voltage in case of the first breakdown at repetitive breakdown has decreased by 30...40%, remaining 2-3 times higher than in the first case

  12. Neural dynamics during repetitive visual stimulation

    Science.gov (United States)

    Tsoneva, Tsvetomira; Garcia-Molina, Gary; Desain, Peter

    2015-12-01

    Objective. Steady-state visual evoked potentials (SSVEPs), the brain responses to repetitive visual stimulation (RVS), are widely utilized in neuroscience. Their high signal-to-noise ratio and ability to entrain oscillatory brain activity are beneficial for their applications in brain-computer interfaces, investigation of neural processes underlying brain rhythmic activity (steady-state topography) and probing the causal role of brain rhythms in cognition and emotion. This paper aims at analyzing the space and time EEG dynamics in response to RVS at the frequency of stimulation and ongoing rhythms in the delta, theta, alpha, beta, and gamma bands. Approach.We used electroencephalography (EEG) to study the oscillatory brain dynamics during RVS at 10 frequencies in the gamma band (40-60 Hz). We collected an extensive EEG data set from 32 participants and analyzed the RVS evoked and induced responses in the time-frequency domain. Main results. Stable SSVEP over parieto-occipital sites was observed at each of the fundamental frequencies and their harmonics and sub-harmonics. Both the strength and the spatial propagation of the SSVEP response seem sensitive to stimulus frequency. The SSVEP was more localized around the parieto-occipital sites for higher frequencies (>54 Hz) and spread to fronto-central locations for lower frequencies. We observed a strong negative correlation between stimulation frequency and relative power change at that frequency, the first harmonic and the sub-harmonic components over occipital sites. Interestingly, over parietal sites for sub-harmonics a positive correlation of relative power change and stimulation frequency was found. A number of distinct patterns in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz) and beta (15-30 Hz) bands were also observed. The transient response, from 0 to about 300 ms after stimulation onset, was accompanied by increase in delta and theta power over fronto-central and occipital sites, which returned to baseline

  13. The Effect of Repetition on Tempo Preferences of Elementary Children.

    Science.gov (United States)

    Moskovitz, Elisa M.

    1992-01-01

    Reports on a study of children's preferences between slow and fast tempo classical music excerpts. Finds that students preferred music with a slow tempo. Concludes that repetition had a positive effect on children's preferences. (CFR)

  14. Is perfectionism associated with academic burnout through repetitive negative thinking?

    Science.gov (United States)

    Garratt-Reed, David; Howell, Joel; Hayes, Lana; Boyes, Mark

    2018-01-01

    Academic burnout is prevalent among university students, although understanding of what predicts burnout is limited. This study aimed to test the direct and indirect relationship between two dimensions of perfectionism (Perfectionistic Concerns and Perfectionistic Strivings) and the three elements of Academic Burnout (Exhaustion, Inadequacy, and Cynicism) through Repetitive Negative Thinking. In a cross-sectional survey, undergraduate students ( n  = 126, M age = 23.64, 79% female) completed well-validated measures of Perfectionism, Repetitive Negative Thinking, and Academic Burnout. Perfectionistic Concerns was directly associated with all elements of burnout, as well as indirectly associated with Exhaustion and Cynicism via Repetitive Negative Thinking. Perfectionistic Strivings was directly associated with less Inadequacy and Cynicism; however, there were no indirect associations between Perfectionistic Strivings and Academic Burnout operating through Repetitive Negative Thinking. Repetitive Negative Thinking was also directly related to more burnout Exhaustion and Inadequacy, but not Cynicism. It is concluded that future research should investigate whether interventions targeting Perfectionistic Concerns and Repetitive Negative Thinking can reduce Academic Burnout in university students.

  15. Negative effects of item repetition on source memory.

    Science.gov (United States)

    Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L; Johnson, Marcia K

    2012-08-01

    In the present study, we explored how item repetition affects source memory for new item-feature associations (picture-location or picture-color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item repetition also had a negative effect on source memory when different source dimensions were used in Phases 1 and 2 (Experiment 3) and when participants were explicitly instructed to learn source information in Phase 2 (Experiments 4 and 5). Importantly, when the order between Phases 1 and 2 was reversed, such that item repetition occurred after the encoding of critical item-source combinations, item repetition no longer affected source memory (Experiment 6). Overall, our findings did not support predictions based on item predifferentiation, within-dimension source interference, or general interference from multiple traces of an item. Rather, the findings were consistent with the idea that prior item repetition reduces attention to subsequent presentations of the item, decreasing the likelihood that critical item-source associations will be encoded.

  16. Recency, repetition, and the multidimensional basis of recognition memory.

    Science.gov (United States)

    Buchsbaum, Bradley R; Lemire-Rodger, Sabrina; Bondad, Ashley; Chepesiuk, Alexander

    2015-02-25

    Recency and repetition are two factors that have large effects on human memory performance. One way of viewing the beneficial impact of these variables on recognition memory is to assume that both factors modulate a unidimensional memory trace strength. Although previous functional neuroimaging studies have indicated that recency and repetition may modulate similar brain structures, particularly in the region of the inferior parietal cortex, there is extensive behavioral evidence that human subjects can make independent and accurate recognition memory judgments about both an item's recency and its frequency. In the present study, we used fMRI to examine patterns of brain activity during recognition memory for auditory-verbal stimuli that were parametrically and orthogonally manipulated in terms of recency and number of repetitions. We found in a continuous recognition paradigm that the lateral inferior parietal cortex, a region that has previously been associated with recollective forms of memory, is highly sensitive to recency but not repetition. In a multivariate analysis of whole-brain activation patterns, we found orthogonal components that dissociated recency and repetition variables, indicating largely independent neural bases underlying these two factors. The results demonstrate that although both recency and repetition dramatically improve recognition memory performance, the neural bases for this improvement are dissociable, and thus are difficult to explain in terms of access to a unitary memory trace. Copyright © 2015 the authors 0270-6474/15/353544-11$15.00/0.

  17. Properties of water surface discharge at different pulse repetition rates

    International Nuclear Information System (INIS)

    Ruma,; Yoshihara, K.; Hosseini, S. H. R.; Sakugawa, T.; Akiyama, H.; Akiyama, M.; Lukeš, P.

    2014-01-01

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H 2 O 2 ) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H 2 O 2 and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  18. The Pinus taeda genome is characterized by diverse and highly diverged repetitive sequences

    Directory of Open Access Journals (Sweden)

    Yandell Mark

    2010-07-01

    Full Text Available Abstract Background In today's age of genomic discovery, no attempt has been made to comprehensively sequence a gymnosperm genome. The largest genus in the coniferous family Pinaceae is Pinus, whose 110-120 species have extremely large genomes (c. 20-40 Gb, 2N = 24. The size and complexity of these genomes have prompted much speculation as to the feasibility of completing a conifer genome sequence. Conifer genomes are reputed to be highly repetitive, but there is little information available on the nature and identity of repetitive units in gymnosperms. The pines have extensive genetic resources, with approximately 329000 ESTs from eleven species and genetic maps in eight species, including a dense genetic map of the twelve linkage groups in Pinus taeda. Results We present here the Sanger sequence and annotation of ten P. taeda BAC clones and Genome Analyzer II whole genome shotgun (WGS sequences representing 7.5% of the genome. Computational annotation of ten BACs predicts three putative protein-coding genes and at least fifteen likely pseudogenes in nearly one megabase of sequence. We found three conifer-specific LTR retroelements in the BACs, and tentatively identified at least 15 others based on evidence from the distantly related angiosperms. Alignment of WGS sequences to the BACs indicates that 80% of BAC sequences have similar copies (≥ 75% nucleotide identity elsewhere in the genome, but only 23% have identical copies (99% identity. The three most common repetitive elements in the genome were identified and, when combined, represent less than 5% of the genome. Conclusions This study indicates that the majority of repeats in the P. taeda genome are 'novel' and will therefore require additional BAC or genomic sequencing for accurate characterization. The pine genome contains a very large number of diverged and probably defunct repetitive elements. This study also provides new evidence that sequencing a pine genome using a WGS approach is

  19. Repetitive sequences: the hidden diversity of heterochromatin in prochilodontid fish

    Directory of Open Access Journals (Sweden)

    Maria L. Terencio

    2015-08-01

    Full Text Available The structure and organization of repetitive elements in fish genomes are still relatively poorly understood, although most of these elements are believed to be located in heterochromatic regions. Repetitive elements are considered essential in evolutionary processes as hotspots for mutations and chromosomal rearrangements, among other functions – thus providing new genomic alternatives and regulatory sites for gene expression. The present study sought to characterize repetitive DNA sequences in the genomes of Semaprochilodus insignis (Jardine & Schomburgk, 1841 and Semaprochilodus taeniurus (Valenciennes, 1817 and identify regions of conserved syntenic blocks in this genome fraction of three species of Prochilodontidae (S. insignis, S. taeniurus, and Prochilodus lineatus (Valenciennes, 1836 by cross-FISH using Cot-1 DNA (renaturation kinetics probes. We found that the repetitive fractions of the genomes of S. insignis and S. taeniurus have significant amounts of conserved syntenic blocks in hybridization sites, but with low degrees of similarity between them and the genome of P. lineatus, especially in relation to B chromosomes. The cloning and sequencing of the repetitive genomic elements of S. insignis and S. taeniurus using Cot-1 DNA identified 48 fragments that displayed high similarity with repetitive sequences deposited in public DNA databases and classified as microsatellites, transposons, and retrotransposons. The repetitive fractions of the S. insignis and S. taeniurus genomes exhibited high degrees of conserved syntenic blocks in terms of both the structures and locations of hybridization sites, but a low degree of similarity with the syntenic blocks of the P. lineatus genome. Future comparative analyses of other prochilodontidae species will be needed to advance our understanding of the organization and evolution of the genomes in this group of fish.

  20. Word and nonword repetition in patients with Schizophrenia

    Directory of Open Access Journals (Sweden)

    Alireza Farnam

    2015-08-01

    Full Text Available Introduction: The assessment of the verbal repetition is important in the study of acquired language disorders and neuropsychology. It is helpful in differential diagnosis of aphasia subtypes, auditory breakdowns, and working memory (WM performance. Though different linguistic disorders have been identified in patients with schizophrenia, very little is known about their verbal repetition ability. Methods: The present study was conducted in the inpatient ward of Razi Psychiatric Hospital, Tabriz University of Medical Sciences, Iran, during the year 2013. Participants were: 30 patients diagnosed with schizophrenia during the maintenance phase of treatment and 30 healthy people as control group. They were asked to repeat 15 words and 15 nonwords immediately. The stimuli were 1, 2, and 3 syllabic in Turkish language. Any incorrect repetition scored 1 and correct repetitions scored 0. Lexicalization errors were compared between groups too. Results: Both groups repeated words better than nonwords. Patients showed lower ability to repeat nonwords than controls, especially in 3 syllabics. There was no significant difference in the repetition of words between groups though it was better in controls. Patients with schizophrenia made more errors in both words and nonwords and lexicalization errors were twice more. Conclusion: Lower ability to repeat nonwords (than words in patients with schizophrenia may show the involvement of phonological loop of WM. More lexicalization errors may take place because of dis-inhibition.

  1. Quantifying repetitive speech in autism spectrum disorders and language impairment.

    Science.gov (United States)

    van Santen, Jan P H; Sproat, Richard W; Hill, Alison Presmanes

    2013-10-01

    We report on an automatic technique for quantifying two types of repetitive speech: repetitions of what the child says him/herself (self-repeats) and of what is uttered by an interlocutor (echolalia). We apply this technique to a sample of 111 children between the ages of four and eight: 42 typically developing children (TD), 19 children with specific language impairment (SLI), 25 children with autism spectrum disorders (ASD) plus language impairment (ALI), and 25 children with ASD with normal, non-impaired language (ALN). The results indicate robust differences in echolalia between the TD and ASD groups as a whole (ALN + ALI), and between TD and ALN children. There were no significant differences between ALI and SLI children for echolalia or self-repetitions. The results confirm previous findings that children with ASD repeat the language of others more than other populations of children. On the other hand, self-repetition does not appear to be significantly more frequent in ASD, nor does it matter whether the child's echolalia occurred within one (immediate) or two turns (near-immediate) of the adult's original utterance. Furthermore, non-significant differences between ALN and SLI, between TD and SLI, and between ALI and TD are suggestive that echolalia may not be specific to ALN or to ASD in general. One important innovation of this work is an objective fully automatic technique for assessing the amount of repetition in a transcript of a child's utterances. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

  2. Autism and exergaming: effects on repetitive behaviors and cognition

    Directory of Open Access Journals (Sweden)

    Anderson-Hanley C

    2011-09-01

    Full Text Available Cay Anderson-Hanley, Kimberly Tureck, Robyn L Schneiderman Department of Psychology, Union College, Schenectady, NY, USA Abstract: Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR; in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum. Keywords: autism, repetitive behaviors, exergaming, exercise, executive function

  3. Nanosecond radar system based on repetitive pulsed relativistic BWO

    International Nuclear Information System (INIS)

    Bunkin, B.V.; Gaponov-Grekhov, A.V.; Eltchaninov, A.S.; Zagulov, F.Ya.; Korovin, S.D.; Mesyats, G.A.; Osipov, M.L.; Otlivantchik, E.A.; Petelin, M.I.; Prokhorov, A.M.

    1993-01-01

    The paper presents the results of studies of a nanosecond radar system based on repetitive pulsed relativistic BWO. A pulsed power repetitive accelerator producing electron beams of electron energy 500-700 keV and current 5 kA in pulses of duraction 10 ns with a repetition rate of 100 pps is described. The results of experiments with a high-voltage gas-filled spark gap and a cold-cathode vacuum diode under the conditions of high repetition rates are given. Also presented are the results of studies of a relativistic BWO operating with a wavelength of 3 cm. It is shown that for a high-current beam electron energy of 500-700 keV, the BWO efficiency can reach 35%, the microwave power being 10 9 W. A superconducting solenoid creating a magnetic field of 30 kOe was used for the formation and transportation of the high-current electron beam. In conclusion, the outcome of tests of a nanosecond radar station based on a pulsed power repetitive accelerator and a relativistic BWO is reported

  4. RPERT: Repetitive-Projects Evaluation and Review Technique

    Directory of Open Access Journals (Sweden)

    Remon Fayek Aziz

    2014-03-01

    Full Text Available Estimating expected completion probability of any repetitive construction project with a specified/certain duration including repetitive identical activities by using program evaluation and review technique is the most essential part in construction areas since the activities were had optimistic, most likely and pessimistic durations. This paper focuses on the calculation of expected completion probability of any repetitive construction project within a specified/certain duration (contract duration by using Line Of Balance technique (LOB in case of single or multiple number of crews integrated with Program Evaluation and Review Technique (PERT. Repetitive-Projects Evaluation and Review Technique (RPERT, which is a simplified software, will generate the expected project completion probability of a specified/certain duration (contract duration. RPERT software is designed by java programming code system to provide a number of new and unique capabilities, including: (1 Viewing the expected project completion probability according to a set of specified durations per each identical activity (optimistic time, most likely time, and pessimistic time in the analyzed project; (2 Providing seamless integration with available project time calculations. In order to provide the aforementioned capabilities of RPERT, the system is implemented and developed in four main modules: (1 A user interface module; (2 A database module; (3 A running module; and (4 A processing module. At the end, an illustrative example will be presented to demonstrate and verify the applications of proposed software (RPERT, by using probabilistic calculations for repetitive construction projects.

  5. Body-focused repetitive behavior disorders in ICD-11

    Directory of Open Access Journals (Sweden)

    Jon E. Grant

    2014-01-01

    Full Text Available This article addresses the question of how body-focused repetitive behavior disorders (e.g., trichotillomania and skin-picking disorder should be characterized in ICD-11. The article reviews the historical nosology of the two disorders and the current approaches in DSM-5 and ICD-10. Although data are limited and mixed regarding the optimal relationship between body-focused repetitive behavior disorders and nosological categories, these conditions should be included within the obsessive-compulsive and related disorders category, as this is how most clinicians see these behaviors, and as this may optimize clinical utility. The descriptions of these disorders should largely mirror those in DSM-5, given the evidence from recent field surveys. The recommendations regarding ICD-11 and body-focused repetitive behavior disorders should promote the global identification and treatment of these conditions in primary care settings.

  6. Repetitive control of an electrostatic microbridge actuator: theory and simulation

    International Nuclear Information System (INIS)

    Zhao, Haiyu; Rahn, Christopher D

    2010-01-01

    Electrostatic microactuators are used extensively in MEMS sensors, RF switches and microfluidic pumps. The high bandwidth operation required by these applications complicates the implementation of feedback controllers. This paper designs, proves stability and simulates a feedforward repetitive controller for an electrostatic microbridge. High residual stress creates tension in the microbridge that dominates bending stiffness so a pinned string model with uniform electrostatic force loading is used for model-based control. The control objective is to force the microbridge displacement to follow prescribed spatial and periodic time trajectories. Viscous damping ensures boundedness of the distributed transverse displacement in response to bounded inputs. The average displacement is measured by capacitive sensing and processed offline using a repetitive control algorithm that updates a high speed waveform generator's parameters. Simulations show that the performance depends on the amount of damping. With less than 1% damping in a representative microbridge structure, repetitive control reduces the midspan displacement overshoot by 83%

  7. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation

    DEFF Research Database (Denmark)

    Christensen, Mark Schram; Lundbye-Jensen, Jesper; Grey, Michael James

    2010-01-01

    Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb movement...... and its associated somatosensory feedback. Afferent and efferent neural signalling was abolished in the arm with ischemic nerve block, and in the leg with spinal nerve block. Movement sensation was assessed following trains of high-frequency repetitive transcranial magnetic stimulation applied over...... premotor cortex stimulation was less affected by sensory and motor deprivation than was primary motor cortex stimulation. We propose that repetitive transcranial magnetic stimulation over dorsal premotor cortex produces a corollary discharge that is perceived as movement....

  8. Risk factors for hand-wrist disorders in repetitive work

    DEFF Research Database (Denmark)

    Thomsen, J. F.; Mikkelsen, S.; Andersen, JH

    2007-01-01

    OBJECTIVES: To identify the risk of hand-wrist disorders related to repetitive movements, use of hand force and wrist position in repetitive monotonous work. METHODS: Using questionnaires and physical examinations, the prevalence and incidence of hand-wrist pain and possible extensor tendonitis...... (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of questionnaires and video recordings of homogenous work tasks number of wrist movements, hand force requirements and wrist position were analysed as risk factors for hand-wrist disorders......, controlling for potential personal and psychosocial confounders. All participants were re-examined three times during a follow-up period of three years. RESULTS: Force but not repetition and position was related to hand-wrist pain and possible tendonitis in the baseline analyses showing an exposure...

  9. Comparison of concentric and eccentric bench press repetitions to failure.

    Science.gov (United States)

    Kelly, Stephen B; Brown, Lee E; Hooker, Steven P; Swan, Pamela D; Buman, Matthew P; Alvar, Brent A; Black, Laurie E

    2015-04-01

    Eccentric muscle actions (ECC) are characterized by muscle lengthening, despite actin-myosin crossbridge formation. Muscles acting eccentrically are capable of producing higher levels of force compared with muscles acting concentrically. The purpose of this study was to determine whether ECC bench press yields greater strength than concentric (CON) as determined by 1 repetition maximum (1RM). Additionally, a comparison was made examining differences in the number of repetitions to failure at different relative intensities of 1RM. Thirty healthy men (age = 24.63 ± 5.6 years) were tested for 1RM in CON and ECC bench press and the number of repetitions completed at 60, 70, 80, and 90% 1RM. For CON repetitions, the weight was mechanically lowered to the chest, and the participant pressed it up until the elbows were fully extended. The ECC bench press consisted of lowering a barbell from a fully extended elbow position to the chest in a continuous controlled manner for 3 seconds as determined by electronic metronome. Paired t-tests showed that ECC 1RM (115.99 ± 31.08 kg) was significantly (p ≤ 0.05) greater than CON 1RM (93.56 ± 26.56 kg), and the number of repetitions completed at 90% 1RM was significantly (p ≤ 0.05) greater in ECC (7.67 ± 3.24) as compared with CON (4.57 ± 2.21). There were no significant differences in number of completed repetitions during CON and ECC bench press at 60, 70, and 80% 1RM. These data indicate that ECC actions yield increased force capabilities (∼120%) as compared with CON in the bench press and may be less prone to fatigue, especially at higher intensities. These differences suggest a need to develop unique strategies for training eccentrically.

  10. Negative effects of item repetition on source memory

    OpenAIRE

    Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L.; Johnson, Marcia K.

    2012-01-01

    In the present study, we explored how item repetition affects source memory for new item–feature associations (picture–location or picture–color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item re...

  11. High-repetition-rate short-pulse gas discharge.

    Science.gov (United States)

    Tulip, J; Seguin, H; Mace, P N

    1979-09-01

    A high-average-power short-pulse gas discharge is described. This consists of a volume-preionized transverse discharge of the type used in gas lasers driven by a Blumlein energy storage circuit. The Blumlein circuit is fabricated from coaxial cable, is pulse-charged from a high-repetition-rate Marx-bank generator, and is switched by a high-repetition-rate segmented rail gap. The operation of this discharge under conditions typical of rare-gas halide lasers is described. A maximum of 900 pps was obtained, giving a power flow into the discharge of 30 kW.

  12. Iodine laser of high efficiency and fast repetition rate

    Energy Technology Data Exchange (ETDEWEB)

    Hohla, K; Witte, K J

    1976-07-01

    The scaling laws of an iodine laser of high efficiency and fast repetition rate are reported. The laser is pumped with a new kind of low pressure Hg-UV-lamps which convert 32% of the electrical input in UV-light in the absorption band of the iodine laser and which can be fired up to 100 Hz. Details of a 10 kJ/1 nsec system as dimensions, energy density, repetition rate, flow velocity, gas composition and gas pressure and the overall efficiency are given which is expected to be about 2%.

  13. The Effects of the Training in the Preparation Period on the Repetitive Strength Transformation with Cadet Level Football Players

    Directory of Open Access Journals (Sweden)

    Jovan Gardašević

    2016-06-01

    Full Text Available The main aim of the research was to identify a level of quantitative changes of the repetitive strength with fifteen years old football players under the influence of the programmed football training of a six weeks preparation period. The training programme covered forty-four training units. The research was made on a sample of 120 cadet level football players. To estimate the repetitive strength three tests have been used: Lying-sed for 30 seconds, Push-ups and Lifting upper body while lying on stomach. In the area of comparative statistics, we used discriminant parametric procedure t-test for big paired samples. It can be concluded that there are statistically significant differences in all three variables to estimate the repetitive strength. This confirmed the hypothesis that the expected significant positive quantitative changes of basic-motor abilities influenced by the proposed model of training in preparation period with fifteen years old football players. The authors were guided by the fact that this kind of training program in preparation period is very effective in terms of raising the repetitive strength level with fifteen years old. The obtained results can be directed towards innovation plans and programs in the preparation period, and the adaptation of the same needs of the respective population.

  14. Repetitive flood victims and acceptance of FEMA mitigation offers: an analysis with community-system policy implications.

    Science.gov (United States)

    Kick, Edward L; Fraser, James C; Fulkerson, Gregory M; McKinney, Laura A; De Vries, Daniel H

    2011-07-01

    Of all natural disasters, flooding causes the greatest amount of economic and social damage. The United States' Federal Emergency Management Agency (FEMA) uses a number of hazard mitigation grant programmes for flood victims, including mitigation offers to relocate permanently repetitive flood loss victims. This study examines factors that help to explain the degree of difficulty repetitive flood loss victims experience when they make decisions about relocating permanently after multiple flood losses. Data are drawn from interviews with FEMA officials and a survey of flood victims from eight repetitive flooding sites. The qualitative and quantitative results show the importance of rational choices by flood victims in their mitigation decisions, as they relate to financial variables, perceptions of future risk, attachments to home and community, and the relationships between repetitive flood loss victims and the local flood management officials who help them. The results offer evidence to suggest the value of a more community-system approach to FEMA relocation practices. © 2011 The Author(s). Disasters © Overseas Development Institute, 2011.

  15. Analogous selection processes in declarative and procedural working memory: N-2 list-repetition and task-repetition costs.

    Science.gov (United States)

    Gade, Miriam; Souza, Alessandra S; Druey, Michel D; Oberauer, Klaus

    2017-01-01

    Working memory (WM) holds and manipulates representations for ongoing cognition. Oberauer (Psychology of Learning and Motivation, 51, 45-100, 2009) distinguishes between two analogous WM sub-systems: a declarative WM which handles the objects of thought, and a procedural WM which handles the representations of (cognitive) actions. Here, we assessed whether analogous effects are observed when participants switch between memory sets (declarative representations) and when they switch between task sets (procedural representations). One mechanism assumed to facilitate switching in procedural WM is the inhibition of previously used, but currently irrelevant task sets, as indexed by n-2 task-repetition costs (Mayr & Keele, Journal of Experimental Psychology: General, 129(1), 4-26, 2000). In this study we tested for an analogous effect in declarative WM. We assessed the evidence for n-2 list-repetition costs across eight experiments in which participants switched between memory lists to perform speeded classifications, mental arithmetic, or a local recognition test. N-2 list-repetition costs were obtained consistently in conditions assumed to increase interference between memory lists, and when lists formed chunks in long-term memory. Further analyses across experiments revealed a substantial contribution of episodic memory to n-2 list-repetition costs, thereby questioning the interpretation of n-2 repetition costs as reflecting inhibition. We reanalyzed the data of eight task-switching experiments, and observed that episodic memory also contributes to n-2 task-repetition costs. Taken together, these results show analogous processing principles in declarative and procedural WM, and question the relevance of inhibitory processes for efficient switching between mental sets.

  16. Repetitive Domain-Referenced Testing Using Computers: the TITA System.

    Science.gov (United States)

    Olympia, P. L., Jr.

    The TITA (Totally Interactive Testing and Analysis) System algorithm for the repetitive construction of domain-referenced tests utilizes a compact data bank, is highly portable, is useful in any discipline, requires modest computer hardware, and does not present a security problem. Clusters of related keyphrases, statement phrases, and distractors…

  17. Repetitive endoscopic sinus surgery failure: a role for radical surgery?

    NARCIS (Netherlands)

    Videler, Ward J. M.; Wreesmann, Volkert B.; van der Meulen, Freerk W.; Knegt, Paul P.; Fokkens, Wytske J.

    2006-01-01

    OBJECTIVES: Endoscopic sinus surgery (ESS) is considered to be the golden standard for surgery in patients with chronic rhinosinusitis and nasal polyposis. However, there is still a small group of patients unresponsive despite repetitive surgery. Radical surgery aimed at reduction of the

  18. Nonword Repetition and Language Learning Disorders: A Developmental Contingency Framework

    Science.gov (United States)

    Snowling, Margaret J.

    2006-01-01

    In 1990 Gathercole and Baddeley proposed a strong hypothesis that has generated a wealth of research in the field of language development and disorder. The hypothesis was that phonological memory, as indexed by nonword repetition, is causally related to vocabulary development. Support for the hypothesis came from an impressive range of…

  19. Software-engineering-based model for mitigating Repetitive Strain ...

    African Journals Online (AJOL)

    The incorporation of Information and Communication Technology (ICT) in virtually all facets of human endeavours has fostered the use of computers. This has induced Repetitive Stress Injury (RSI) for continuous and persistent computer users. Proposing a software engineering model capable of enacted RSI force break ...

  20. Intrinsic and Extrinsic Motivation for Stereotypic and Repetitive Behavior

    Science.gov (United States)

    Joosten, Annette V.; Bundy, Anita C.; Einfeld, Stewart L.

    2009-01-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess…

  1. Temporal dynamics of high repetition rate pulsed single longitudinal ...

    Indian Academy of Sciences (India)

    ing (GIG) cavity, single-mode dye laser pumped by high repetition rate ... in a high loss cavity, a detailed theoretical study and optimization of cavity ..... rate for high conversion efficiency and longer pulse width of the single-mode dye laser.

  2. Context-Dependent Repetition Effects on Recognition Memory

    Science.gov (United States)

    Opitz, Bertram

    2010-01-01

    One widely acknowledged way to improve our memory performance is to repeatedly study the to be learned material. One aspect that has received little attention in past research regards the context sensitivity of this repetition effect, that is whether the item is repeated within the same or within different contexts. The predictions of a…

  3. Autism and exergaming: effects on repetitive behaviors and cognition.

    Science.gov (United States)

    Anderson-Hanley, Cay; Tureck, Kimberly; Schneiderman, Robyn L

    2011-01-01

    Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR); in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum.

  4. Heavy-duty high-repetition-rate generators

    NARCIS (Netherlands)

    Heesch, van E.J.M.; Yan, K.; Pemen, A.J.M.

    2002-01-01

    We present our results on high-power repetitive pulse sources for continuous operation. Two 1-10-kW systems using advanced spark gap technology and a transmission line transformer have been tested for several hundred hours at a 60-MW pulse level. High reliability and above 90% overall efficiency are

  5. Analysis of repetitive DNA in chromosomes by flow cytometry

    NARCIS (Netherlands)

    Brind'Amour, Julie; Lansdorp, Peter M.

    We developed a flow cytometry method, chromosome flow fluorescence in situ hybridization (FISH), called CFF, to analyze repetitive DNA in chromosomes using FISH with directly labeled peptide nucleic acid (PNA) probes. We used CFF to measure the abundance of interstitial telomeric sequences in

  6. Impact of repetitive DNA on sex chromosome evolution in plants

    Czech Academy of Sciences Publication Activity Database

    Hobza, Roman; Kubát, Z.; Čegan, R.; Jesionek, W.; Vyskot, B.; Kejnovský, E.

    2015-01-01

    Roč. 23, č. 3 (2015), s. 561-570 ISSN 0967-3849 R&D Projects: GA ČR GBP501/12/G090; GA ČR GAP501/12/2220 Institutional support: RVO:61389030 Keywords : repetitive sequences * transposable elements * tandem repeats (satellites) Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.590, year: 2015

  7. Post-exercise cortical depression following repetitive passive finger movement.

    Science.gov (United States)

    Otsuka, Ryohei; Sasaki, Ryoki; Tsuiki, Shota; Kojima, Sho; Onishi, Hideaki

    2017-08-24

    This study aimed to clarify the influence of range of repetitive passive finger movement on corticospinal excitability. Thirteen healthy subjects participated in this study. Passive index finger adduction-abduction movements were performed from 15° abduction to 15° adduction, 15° abduction to 0°, 0° to 15° adduction, and 15° adduction to 30° adduction, each at 15°/s for 10min on separate days. Motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation and M- and F-waves were measured before and after each repetitive passive index finger movement protocol to evaluate changes in corticospinal excitability. MEP amplitude significantly decreased after all passive movements, while F-wave amplitude, F-wave persistence, and M-wave amplitude remained stable. These results suggest that cortical excitability decreases after repetitive passive movement. However, the range of repetitive passive movement does not markedly influence the magnitude of cortical depression. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Use of Repetitive Transcranial Magnetic Stimulation for Treatment in Psychiatry

    NARCIS (Netherlands)

    Aleman, Andre

    The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory verbal hallucinations in schizophrenia.

  9. Repetitive controller for improving grid-connected photovoltaic systems

    NARCIS (Netherlands)

    Almeida, de P.M.; Duarte, J.L.; Ribeiro, P.F.; Barbosa, P.G.

    2014-01-01

    This study presents the modelling and design steps of a discrete time recursive repetitive controller (RC) to be used in a grid-connected photovoltaic (PV) system. It is shown that the linear synchronous reference frame proportional-integral controller, originally designed to control the converter's

  10. Task type and incidental L2 vocabulary learning: Repetition versus ...

    African Journals Online (AJOL)

    This study investigated the effect of task type on incidental L2 vocabulary learning. The different tasks investigated in this study differed in terms of repetition of encounters and task involvement load. In a within-subjects design, 72 Iranian learners of English practised 18 target words in three exercise conditions: three ...

  11. Exact Repetition as Input Enhancement in Second Language Acquisition.

    Science.gov (United States)

    Jensen, Eva Dam; Vinther, Thora

    2003-01-01

    Reports on two studies on input enhancement used to support learners' selection of focus of attention in Spanish second language listening material. Input consisted of video recordings of dialogues between native speakers. Exact repetition and speech rate reduction were examined for effect on comprehension, acquisition of decoding strategies, and…

  12. Repetition of Attempted Suicide Among Immigrants in Europe

    Science.gov (United States)

    Lipsicas, Cendrine Bursztein; Mäkinen, Ilkka Henrik; Wasserman, Danuta; Apter, Alan; Kerkhof, Ad; Michel, Konrad; Renberg, Ellinor Salander; van Heeringen, Kees; Värnik, Airi; Schmidtke, Armin

    2014-01-01

    Objectives To compare frequencies of suicide attempt repetition in immigrants and local European populations, and the timing of repetition in these groups. Method: Data from 7 European countries, comprising 10 574 local and 3032 immigrant subjects, were taken from the World Health Organization European Multicentre Study on Suicidal Behaviour and the ensuing Monitoring Suicidal Behaviour in Europe (commonly referred to as MONSUE) project. The relation between immigrant status and repetition of suicide attempt within 12-months following first registered attempt was analyzed with binary logistic regression, controlling for sex, age, and method of attempt. Timing of repetition was controlled for sex, age, and the recommended type of aftercare. Results: Lower odds of repeating a suicide attempt were found in Eastern European (OR 0.50; 95% CI 0.41 to 0.61, P Europe stands in contrast to their markedly higher tendency to attempt suicide in general, possibly pointing to situational stress factors related to their suicidal crisis that are less persistent over time. Our findings also raise the possibility that suicide attempters and repeaters constitute only partially overlapping populations. PMID:25565687

  13. Understanding the relationship between repetition priming and mere exposure.

    Science.gov (United States)

    Butler, Laurie T; Berry, Dianne C

    2004-11-01

    Over the last two decades interest in implicit memory, most notably repetition priming, has grown considerably. During the same period, research has also focused on the mere exposure effect. Although the two areas have developed relatively independently, a number of studies has described the mere exposure effect as an example of implicit memory. Tacit in their comparisons is the assumption that the effect is more specifically a demonstration of repetition priming. Having noted that this assumption has attracted relatively little attention, this paper reviews current evidence and shows that it is by no means conclusive. Although some evidence is suggestive of a common underlying mechanism, even a modified repetition priming (perceptual fluency/attribution) framework cannot accommodate all of the differences between the two phenomena. Notwithstanding this, it seems likely that a version of this theoretical framework still offers the best hope of a comprehensive explanation for the mere exposure effect and its relationship to repetition priming. As such, the paper finishes by offering some initial guidance as to ways in which the perceptual fluency/attribution framework might be extended, as well as outlining important areas for future research.

  14. Instruction, Repetition, Discovery: Restoring the Historical Educational Role of Practice

    Science.gov (United States)

    Trninic, Dragan

    2018-01-01

    This conceptual paper considers what it would mean to take seriously Freudenthal's suggestion that mathematics should be taught like swimming. The general claim being made is that "direct instruction" and "discovery" are not opposite but complementary, linked by repetitive yet explorative practice. This claim is elaborated…

  15. Phylogenetic analysis of the genus Hordeum using repetitive DNA sequences

    DEFF Research Database (Denmark)

    Svitashev, S.; Bryngelsson, T.; Vershinin, A.

    1994-01-01

    A set of six cloned barley (Hordeum vulgare) repetitive DNA sequences was used for the analysis of phylogenetic relationships among 31 species (46 taxa) of the genus Hordeum, using molecular hybridization techniques. In situ hybridization experiments showed dispersed organization of the sequences...

  16. Pulsed electron beam generation with fast repetitive double pulse system

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Surender Kumar; Deb, Pankaj; Shyam, Anurag, E-mail: surender80@gmail.com [Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Visakhapatnam (India); Sharma, Archana [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai (India)

    2014-07-01

    Longer duration high voltage pulse (∼ 100 kV, 260 ns) is generated and reported using helical pulse forming line in compact geometry. The transmission line characteristics of the helical pulse forming line are also used to develop fast repetition double pulse system with very short inter pulse interval. It overcomes the limitations caused due to circuit parameters, power supplies and load characteristics for fast repetitive high voltage pulse generation. The high voltage double pulse of 100 kV, 100 ns with an inter pulse repetition interval of 30 ns is applied across the vacuum field emission diode for pulsed electron beam generation. The electron beam is generated from cathode material by application of negative high voltage (> 100 kV) across the diode by explosive electron emission process. The vacuum field emission diode is made of 40 mm diameter graphite cathode and SS mesh anode. The anode cathode gap was 6 mm and the drift tube diameter was 10 cm. The initial experimental results of pulsed electron beam generation with fast repetitive double pulse system are reported and discussed. (author)

  17. Evidence for the involvement of a nonlexical route in the repetition of familiar words: A comparison of single and dual route models of auditory repetition.

    Science.gov (United States)

    Hanley, J Richard; Dell, Gary S; Kay, Janice; Baron, Rachel

    2004-03-01

    In this paper, we attempt to simulate the picture naming and auditory repetition performance of two patients reported by Hanley, Kay, and Edwards (2002), who were matched for picture naming score but who differed significantly in their ability to repeat familiar words. In Experiment 1, we demonstrate that the model of naming and repetition put forward by Foygel and Dell (2000) is better able to accommodate this pattern of performance than the model put forward by Dell, Schwartz, Martin, Saffran, and Gagnon (1997). Nevertheless, Foygel and Dell's model underpredicted the repetition performance of both patients. In Experiment 2, we attempt to simulate their performance using a new dual route model of repetition in which Foygel and Dell's model is augmented by an additional nonlexical repetition pathway. The new model provided a more accurate fit to the real-word repetition performance of both patients. It is argued that the results provide support for dual route models of auditory repetition.

  18. Active power filter for harmonic compensation using a digital dual-mode-structure repetitive control approach

    DEFF Research Database (Denmark)

    Zou, Zhixiang; Wang, Zheng; Cheng, Ming

    2012-01-01

    This paper presents an digital dual-mode-structure repetitive control approach for the single-phase shunt active power filter (APF), which aims to enhance the tracking ability and eliminate arbitrary order harmonic. The proposed repetitive control scheme blends the characteristics of both odd......-harmonic repetitive control and even-harmonic repetitive control. Moreover, the convergence rate is faster than conventional repetitive controller. Additionally, the parameters have been designed and optimized for the dual-mode structure repetitive control to improve the performance of APF system. Experimental...

  19. Repetition rate multiplication of frequency comb using all-pass fiber resonator

    International Nuclear Information System (INIS)

    Yang, Lijun; Yang, Honglei; Zhang, Hongyuan; Wei, Haoyun; Li, Yan

    2016-01-01

    We propose a stable method for repetition rate multiplication of a 250-MHz Er-fiber frequency comb by a phase-locked all-pass fiber ring resonator, whose phase-locking configuration is simple. The optical path length of the fiber ring resonator is automatically controlled to be accurately an odd multiple of half of the original cavity length using an electronical phase-locking unit with an optical delay line. As for shorter cavity length of the comb, high-order odd multiple is preferable. Because the power loss depends only on the net-attenuation of the fiber ring resonator, the energetic efficiency of the proposed method is high. The input and output optical spectrums show that the spectral width of the frequency comb is clearly preserved. Besides, experimental results show less pulse intensity fluctuation and 35 dB suppression ratio of side-modes while providing a good long-term and short-term frequency stability. Higher-order repetition rate multiplication to several GHz can be obtained by using several fiber ring resonators in cascade configuration.

  20. Repetition rate multiplication of frequency comb using all-pass fiber resonator

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lijun; Yang, Honglei; Zhang, Hongyuan; Wei, Haoyun; Li, Yan, E-mail: liyan@mail.tsinghua.edu.cn [State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084 (China)

    2016-09-15

    We propose a stable method for repetition rate multiplication of a 250-MHz Er-fiber frequency comb by a phase-locked all-pass fiber ring resonator, whose phase-locking configuration is simple. The optical path length of the fiber ring resonator is automatically controlled to be accurately an odd multiple of half of the original cavity length using an electronical phase-locking unit with an optical delay line. As for shorter cavity length of the comb, high-order odd multiple is preferable. Because the power loss depends only on the net-attenuation of the fiber ring resonator, the energetic efficiency of the proposed method is high. The input and output optical spectrums show that the spectral width of the frequency comb is clearly preserved. Besides, experimental results show less pulse intensity fluctuation and 35 dB suppression ratio of side-modes while providing a good long-term and short-term frequency stability. Higher-order repetition rate multiplication to several GHz can be obtained by using several fiber ring resonators in cascade configuration.

  1. High genetic diversity among Mycobacterium tuberculosis strains in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Taher Azimi

    2018-05-01

    Full Text Available Introduction: Tuberculosis (TB still remains an important public health problem in Iran. The genotyping of Mycobacterium tuberculosis isolates is expected to lead to a better understanding of M. tuberculosis transmission in Tehran, the most populated city of Iran. Materials and Methods: A total of 2300 clinical specimens were obtained from TB suspected patients who were referred to a TB center in Tehran from Jan 2014 to Dec 2016. Identification was performed using both conventional and molecular methods. The presence of resistance to rifampicin was examined by the GeneXpert MTB/RIF. The standard 15-locus mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR typing method was applied to genotype of clinical isolates. Results: Of 2300 specimens, 80 isolates were identified as M. tuberculosis by using biochemical and molecular tests. Of 80 M. tuberculosis isolates, 76 (95% had unique genotypic profiles and 4 (5% shared a profile with one or more other strains. Based on single loci variation (SLV 4 clonal complexes were observed. NEW-1 was found to be the most predominant lineage (22.5% followed by West African (1.25%, Central Asian (CAS/Delhi (1.25%, Bovis (1.25%, H37Rv (1.25% and multiple matches (1.25%. Loci MIRU10, MIRU26, MTUB21 and QUB26 were found as highly discriminative. No mutation was detected in the hotspot region of rifampicin by using GeneXpert MTB/RIF. Conclusions: Our study findings show that there was considerable genotypic diversity among M. tuberculosis isolates in Tehran. The 15-locus MIRU-VNTR showed high HGDI and could be used as a first-line genotyping method for epidemiological studies. Keywords: Mycobacterium tuberculosis, Genotyping, MIRU-VNTR, Tehran, Iran

  2. Predominance of Central Asian and European families among Mycobacterium tuberculosis isolates in Kashmir Valley, India.

    Science.gov (United States)

    Bashir, Gulnaz; Wani, Tehmeena; Sharma, Pragya; Katoch, V M; Lone, Rubina; Shah, Azra; Katoch, Kiran; Kakru, D K; Chauhan, Devendra Singh

    2017-10-01

    As there are no data available regarding the strains of Mycobacterium tuberculosis circulating in Kashmir Valley, India, the current study aimed at describing the genetic diversity of M. tuberculosis strains in this region, by spoligotyping and 12-locus-based MIRU-VNTR typing (Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat). Sputa from 207 smear positive cases with newly diagnosed pulmonary tuberculosis were subjected to culture for M. tuberculosis. Eighty-five isolates confirmed as M. tuberculosis were subjected to drug susceptibility testing and molecular typing by spoligotyping and MIRU-VNTRs. Drug susceptibility results of 72 isolates revealed 76.3% as fully sensitive while 5.5% as multidrug resistant (MDR). Spoligotyping of 85 isolates detected 42 spoligotypes with 50 isolates (58.8%) clustered into seven spoligotypes. SIT26/CAS1_Del was the major spoligotype (23, 27%) followed by SIT127/H4 (12, 14.1%); CAS lineage (37.6%) was predominant, followed by Haarlem (25.8%) and ill-defined T clade (23.5%). MIRU-VNTR analysis displayed 82 MIRU patterns from 85 strains, including 3 small clusters and 79 unique. MIRU 26 was found to be the most discriminatory locus. Kashmir Valley has CAS as the predominant lineage of M. tuberculosis similar to the rest of the Indian sub-continent, while it is peculiar in having Euro American lineages such as Haarlem and ill-defined T clade. Copyright © 2017 Tuberculosis Association of India. Published by Elsevier B.V. All rights reserved.

  3. Perseveration and other repetitive verbal behaviors: functional dissociations.

    Science.gov (United States)

    Christman, Sarah S; Boutsen, Frank R; Buckingham, Hugh W

    2004-11-01

    This article will review types of perseveration from a neurolinguistic perspective. During the course of the article, continuous, stuck-in-set, and recurrent perseveration will be placed in contradistinction to several other types of repetitive behaviors commonly associated with neurogenic communication disorders. These include echolalia in mixed transcortical aphasia; conduite d'approche and conduite d'ecart in fluent aphasias; lexical and nonlexical automatisms in nonfluent aphasias; palilalia in neuromotor disorders, such as Parkinson's disease (PD); and sound, syllable, word, and phrase repetitions in neurogenic stuttering. When differentiating these phenomena from perseveration, it is helpful to consider the salient factors that condition observed behaviors in individual patients, such as overall speech fluency, inventory of available utterances, nature of eliciting tasks, and propositionality of responses. Information such as communication disorder diagnosis, underlying etiology, and known sites of lesion from each patient's total clinical profile may also assist with differentiation.

  4. Repetitive motion planning and control of redundant robot manipulators

    CERN Document Server

    Zhang, Yunong

    2013-01-01

    Repetitive Motion Planning and Control of Redundant Robot Manipulators presents four typical motion planning schemes based on optimization techniques, including the fundamental RMP scheme and its extensions. These schemes are unified as quadratic programs (QPs), which are solved by neural networks or numerical algorithms. The RMP schemes are demonstrated effectively by the simulation results based on various robotic models; the experiments applying the fundamental RMP scheme to a physical robot manipulator are also presented. As the schemes and the corresponding solvers presented in the book have solved the non-repetitive motion problems existing in redundant robot manipulators, it is of particular use in applying theoretical research based on the quadratic program for redundant robot manipulators in industrial situations. This book will be a valuable reference work for engineers, researchers, advanced undergraduate and graduate students in robotics fields. Yunong Zhang is a professor at The School of Informa...

  5. Interaction of Repetitively Pulsed High Energy Laser Radiation With Matter

    Science.gov (United States)

    Hugenschmidt, Manfred

    1986-10-01

    The paper is concerned with laser target interaction processes involving new methods of improving the overall energy balance. As expected theoretically, this can be achieved with high repetition rate pulsed lasers even for initially highly reflecting materials, such as metals. Experiments were performed by using a pulsed CO2 laser at mean powers up to 2 kW and repetition rates up to 100 Hz. The rates of temperature rise of aluminium for example were thereby increased by lore than a factor of 3 as compared to cw-radiation of comparable power density. Similar improvements were found for the overall absorptivities that were increased by this method by more than an order of magnitude.

  6. Long-term repetition priming with symmetrical polygons and words.

    Science.gov (United States)

    Kersteen-Tucker, Z

    1991-01-01

    In two different tasks, subjects were asked to make lexical decisions (word or nonword) and symmetry judgments (symmetrical or nonsymmetrical) about two-dimensional polygons. In both tasks, every stimulus was repeated at one of four lags (0, 1, 4, or 8 items interposed between the first and second stimulus presentations). This paradigm, known as repetition priming, revealed comparable short-term priming (Lag 0) and long-term priming (Lags 1, 4, and 8) both for symmetrical polygons and for words. A shorter term component (Lags 0 and 1) of priming was observed for nonwords, and only very short-term priming (Lag 0) was observed for nonsymmetrical polygons. These results indicate that response facilitation accruing from repeated exposure can be observed for stimuli that have no preexisting memory representations and suggest that perceptual factors contribute to repetition-priming effects.

  7. Closed cycle high-repetition-rate pulsed HF laser

    Science.gov (United States)

    Harris, Michael R.; Morris, A. V.; Gorton, Eric K.

    1997-04-01

    The design and performance of a closed cycle high repetition rate HF laser is described. A short pulse, glow discharge is formed in a 10 SF6:1 H2 gas mixture at a total pressure of approximately 110 torr within a 15 by 0.5 by 0.5 cm3 volume. Transverse, recirculated gas flow adequate to enable repetitive operation up to 3 kHz is imposed by a centrifugal fan. The fan also forces the gas through a scrubber cell to eliminate ground state HF from the gas stream. An automated gas make-up system replenishes spent gas removed by the scrubber. Typical mean laser output powers up to 3 W can be maintained for extended periods of operation.

  8. Spared behavioral repetition effects in Alzheimer's disease linked to an altered neural mechanism at posterior cortex.

    Science.gov (United States)

    Broster, Lucas S; Li, Juan; Wagner, Benjamin; Smith, Charles D; Jicha, Gregory A; Schmitt, Frederick A; Munro, Nancy; Haney, Ryan H; Jiang, Yang

    2018-02-20

    Individuals with dementia of the Alzheimer type (AD) classically show disproportionate impairment in measures of working memory, but repetition learning effects are relatively preserved. As AD affects brain regions implicated in both working memory and repetition effects, the neural basis of this discrepancy is poorly understood. We hypothesized that the posterior repetition effect could account for this discrepancy due to the milder effects of AD at visual cortex. Participants with early AD, amnestic mild cognitive impairment (MCI), and healthy controls performed a working memory task with superimposed repetition effects while electroencephalography was collected to identify possible neural mechanisms of preserved repetition effects. Participants with AD showed preserved behavioral repetition effects and a change in the posterior repetition effect. Visual cortex may play a role in maintained repetition effects in persons with early AD.

  9. High repetition rate burst-mode spark gap

    International Nuclear Information System (INIS)

    Faltens, A.; Reginato, L.; Hester, R.; Chesterman, A.; Cook, E.; Yokota, T.; Dexter, W.

    1978-01-01

    Results are presented on the design and testing of a pressurized gas blown spark gap switch capable of high repetition rates in a burst mode of operation. The switch parameters which have been achieved are as follows: 220-kV, 42-kA, a five pulse burst at 1-kHz, 12-ns risetime, 2-ns jitter at a pulse width of 50-ns

  10. Context-dependent repetition effects on recognition memory.

    OpenAIRE

    Opitz, B

    2010-01-01

    One widely acknowledged way to improve our memory performance is to repeatedly study the to be learned material. One aspect that has received little attention in past research regards the context sensitivity of this repetition effect, that is whether the item is repeated within the same or within different contexts. The predictions of a neuro-computational model (O'Reilly & Norman, 2002) were tested in an experiment requiring participants to study visual objects either once or three times. Cr...

  11. Repetitive nanosecond electron accelerators type URT-1 for radiation technology

    Science.gov (United States)

    Sokovnin, S. Yu.; Balezin, M. E.

    2018-03-01

    The electron accelerator URT-1М-300 for mobile installation was created for radiation disinfecting to correct drawbacks that were found the URT-1M electron accelerator operation (the accelerating voltage up to 1 МV, repetition rate up to 300 pps, electron beam size 400 × 100 mm, the pulse width about 100 ns). Accelerator configuration was changed that allowed to reduce significantly by 20% tank volume with oil where is placed the system of formation high-voltage pulses, thus the average power of the accelerator is increased by 6 times at the expense of increase in pulses repetition rate. Was created the system of the computerized monitoring parameters (output parameters and thermal mode) and remote control of the accelerator (charge voltage, pulse repetition rate), its elements and auxiliary systems (heat of the thyratron, vacuum system), the remote control panel is connected to the installation by the fiber-optical channel, what lightens the work for service personnel. For generating an electron beam up to 400 mm wide there are used metal- ceramic] and metal-dielectric cold cathodes of several emission elements (plates) with a non-uniform distribution of the electron beam current density on the output foil ± 15%. It was found that emission drop of both type of cathodes, during the operation at the high repetition rate (100 pps) is substantial at the beginning of the process, and then proceeds rather slowly that allows for continuous operation up to 40 h. Experiments showed that linear dependence of the voltage and a signal from the pin-diode remains within the range of the charge voltage 45-65 kV. Thus, voltage increases from 690 to 950 kV, and the signal from the pin-diode - from (2,8-4,6)*104 Gy/s. It allows to select electron energy quite precisely with consideration of the radiation technology requirements.

  12. A Repetition Test for Pseudo-Random Number Generators

    OpenAIRE

    Gil, Manuel; Gonnet, Gaston H.; Petersen, Wesley P.

    2017-01-01

    A new statistical test for uniform pseudo-random number generators (PRNGs) is presented. The idea is that a sequence of pseudo-random numbers should have numbers reappear with a certain probability. The expectation time that a repetition occurs provides the metric for the test. For linear congruential generators (LCGs) failure can be shown theoretically. Empirical test results for a number of commonly used PRNGs are reported, showing that some PRNGs considered to have good statistical propert...

  13. Progress toward a microsecond duration, repetitively pulsed, intense- ion beam

    International Nuclear Information System (INIS)

    Davis, H.A.; Olson, J.C.; Reass, W.A.; Coates, D.M.; Hunt, J.W.; Schleinitz, H.M.; Greenly, J.B.

    1996-01-01

    A number of intense ion beams applications are emerging requiring repetitive high-average-power beams. These applications include ablative deposition of thin films, rapid melt and resolidification for surface property enhancement, advanced diagnostic neutral beams for the next generation of Tokamaks, and intense pulsed-neutron sources. We are developing a 200-250 keV, 15 kA, 1 μs duration, 1-30 Hz intense ion beam accelerator to address these applications

  14. Effects of Navigated Repetitive Transcranial Magnetic Stimulation After Stroke.

    Science.gov (United States)

    Chervyakov, Alexander V; Poydasheva, Alexandra G; Lyukmanov, Roman H; Suponeva, Natalia A; Chernikova, Ludmila A; Piradov, Michael A; Ustinova, Ksenia I

    2018-03-01

    The purpose of this study was to test the effects of navigated repetitive transcranial magnetic stimulation, delivered in different modes, on motor impairments and functional limitations after stroke. The study sample included 42 patients (58.5 ± 10.7 years; 26 males) who experienced a single unilateral stroke (1-12 months previously) in the area of the middle cerebral artery. Patients completed a course of conventional rehabilitation, together with 10 sessions of navigated repetitive transcranial magnetic stimulation or sham stimulation. Stimulation was scheduled five times a week over two consecutive weeks in an inpatient clinical setting. Patients were randomly assigned to one of four groups and received sham stimulation (n = 10), low-frequency (1-Hz) stimulation of the nonaffected hemisphere (n = 11), high-frequency (10-Hz) stimulation of the affected hemisphere (n = 13), or sequential combination of low- and high-frequency stimulations (n = 8). Participants were evaluated before and after stimulation with clinical tests, including the arm and hand section of the Fugl-Meyer Assessment Scale, modified Ashworth Scale of Muscle Spasticity, and Barthel Index of Activities of Daily Living. Participants in the three groups receiving navigated repetitive transcranial magnetic stimulation showed improvements in arm and hand functions on the Fugl-Meyer Stroke Assessment Scale. Ashworth Scale of Muscle Spasticity and Barthel Index scores were significantly reduced in groups receiving low- or high-frequency stimulation alone. Including navigated repetitive transcranial magnetic stimulation in a conventional rehabilitation program positively influenced motor and functional recovery in study participants, demonstrating the clinical potential of the method. The results of this study will be used for designing a large-scale clinical trial.

  15. Repetitive display system of line profiles for Doppler broadening measurement

    International Nuclear Information System (INIS)

    Mohri, A.; Narihara, K.; Haba, K.

    1982-10-01

    Line profiles of impurities in visible and ultraviolet regions are repetitively displayed on a CRT with an interval of 250 mu s or 500 mu s, using a system composed of a Czerny-Turner monochromator with 1 m F.L., a self-resonant optical scanner, a photomultiplier shielded against hard X-rays and electronic circuits. The profile resolution is 0.035 nm FWHM. This system can be used in the environment of strong hard X-rays. (author)

  16. Repetitive Observation of Coniferous Samples in ESEM and SEM

    Czech Academy of Sciences Publication Activity Database

    Tihlaříková, Eva; Neděla, Vilém

    2015-01-01

    Roč. 21, S3 (2015), s. 1695-1696 ISSN 1431-9276 R&D Projects: GA ČR(CZ) GA14-22777S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : SEM * ESEM * biological samples * repetitive observation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.730, year: 2015

  17. The Influence of Level of Processing on Advertising Repetition Effects.

    OpenAIRE

    Nordhielm, Christie L

    2002-01-01

    This research examines whether or not repetition of features of a stimulus are subject to wear-out effects that have until now only been tested for the stimulus as a whole. When consumers process features in either a shallower or deeper manner, the level of processing performed dictates the effect of repeated feature exposure on their judgments. When repeated exposures to features are processed in a shallower fashion, there is an enhancement in evaluations with no subsequent downturn, whereas...

  18. High repetition rate ultrashort laser cuts a path through fog

    Science.gov (United States)

    de la Cruz, Lorena; Schubert, Elise; Mongin, Denis; Klingebiel, Sandro; Schultze, Marcel; Metzger, Thomas; Michel, Knut; Kasparian, Jérôme; Wolf, Jean-Pierre

    2016-12-01

    We experimentally demonstrate that the transmission of a 1030 nm, 1.3 ps laser beam of 100 mJ energy through fog increases when its repetition rate increases to the kHz range. Due to the efficient energy deposition by the laser filaments in the air, a shockwave ejects the fog droplets from a substantial volume of the beam, at a moderate energy cost. This process opens prospects for applications requiring the transmission of laser beams through fogs and clouds.

  19. High-repetition-rate hydrogen chamber: Preliminary studies

    International Nuclear Information System (INIS)

    1967-01-01

    This report is a conclusion to the tests realised with an experimental bubbles chamber in view to study the possibilities to increase the repetition rate. The more important parameters (the evolution of the bubbles, the expansion system) are considered in a theoretical way. Then the hardware is described. To end, experimental results are compared with the first evaluations. The calculations and the experimentation are against an oscillation system for the expansion. A system with a locking is to he considered. (authors) [fr

  20. The Role of Memory Processes in Repetition Blindness

    Science.gov (United States)

    Johnston, James C.; Hochhaus, Larry; Null, Cynthia H. (Technical Monitor)

    1995-01-01

    We investigated whether Repetition Blindness (RB) in processing RSVP strings depends critically on memory demands. When all items in the sequence had to be reported, strong RB was found. When only the 2 critical items (cued by color) had to be reported, no RB was found. Preliminary results show that imposing a separate memory load, while reporting only the critical items, also produces little RB. Implications for the processing locus of RB will be discussed.

  1. A compact, repetitive accelerator for military and industrial applications

    International Nuclear Information System (INIS)

    Zutavern, F.J.; O'Malley, M.W.; Ruebush, M.H.; Rinehart, L.F.; Loubriel, G.M.; Babcock, S.R.; Denison, G.J.

    1998-04-01

    A compact, short pulse, repetitive accelerator has many useful military and commercial applications in biological counter proliferation, materials processing, radiography, and sterilization (medical instruments, waste, and food). The goal of this project was to develop and demonstrate a small, 700 kV accelerator, which can produce 7 kA particle beams with pulse lengths of 10--30 ns at rates up to 50 Hz. At reduced power levels, longer pulses or higher repetition rates (up to 10 kHz) could be achieved. Two switching technologies were tested: (1) spark gaps, which have been used to build low repetition rate accelerators for many years; and (2) high gain photoconductive semiconductor switches (PCSS), a new solid state switching technology. This plan was economical, because it used existing hardware for the accelerator, and the PCSS material and fabrication for one module was relatively inexpensive. It was research oriented, because it provided a test bed to examine the utility of other emerging switching technologies, such as magnetic switches. At full power, the accelerator will produce 700 kV and 7 kA with either the spark gap or PCSS pulser

  2. Sound segregation via embedded repetition is robust to inattention.

    Science.gov (United States)

    Masutomi, Keiko; Barascud, Nicolas; Kashino, Makio; McDermott, Josh H; Chait, Maria

    2016-03-01

    The segregation of sound sources from the mixture of sounds that enters the ear is a core capacity of human hearing, but the extent to which this process is dependent on attention remains unclear. This study investigated the effect of attention on the ability to segregate sounds via repetition. We utilized a dual task design in which stimuli to be segregated were presented along with stimuli for a "decoy" task that required continuous monitoring. The task to assess segregation presented a target sound 10 times in a row, each time concurrent with a different distractor sound. McDermott, Wrobleski, and Oxenham (2011) demonstrated that repetition causes the target sound to be segregated from the distractors. Segregation was queried by asking listeners whether a subsequent probe sound was identical to the target. A control task presented similar stimuli but probed discrimination without engaging segregation processes. We present results from 3 different decoy tasks: a visual multiple object tracking task, a rapid serial visual presentation (RSVP) digit encoding task, and a demanding auditory monitoring task. Load was manipulated by using high- and low-demand versions of each decoy task. The data provide converging evidence of a small effect of attention that is nonspecific, in that it affected the segregation and control tasks to a similar extent. In all cases, segregation performance remained high despite the presence of a concurrent, objectively demanding decoy task. The results suggest that repetition-based segregation is robust to inattention. (c) 2016 APA, all rights reserved).

  3. Repetitive, small-bore two-stage light gas gun

    International Nuclear Information System (INIS)

    Combs, S.K.; Foust, C.R.; Fehling, D.T.; Gouge, M.J.; Milora, S.L.

    1991-01-01

    A repetitive two-stage light gas gun for high-speed pellet injection has been developed at Oak Ridge National Laboratory. In general, applications of the two-stage light gas gun have been limited to only single shots, with a finite time (at least minutes) needed for recovery and preparation for the next shot. The new device overcomes problems associated with repetitive operation, including rapidly evacuating the propellant gases, reloading the gun breech with a new projectile, returning the piston to its initial position, and refilling the first- and second-stage gas volumes to the appropriate pressure levels. In addition, some components are subjected to and must survive severe operating conditions, which include rapid cycling to high pressures and temperatures (up to thousands of bars and thousands of kelvins) and significant mechanical shocks. Small plastic projectiles (4-mm nominal size) and helium gas have been used in the prototype device, which was equipped with a 1-m-long pump tube and a 1-m-long gun barrel, to demonstrate repetitive operation (up to 1 Hz) at relatively high pellet velocities (up to 3000 m/s). The equipment is described, and experimental results are presented. 124 refs., 6 figs., 5 tabs

  4. Inverted U-shaped model: How frequent repetition affects perceived risk

    OpenAIRE

    Xi Lu; Xiaofei Xie; Lu Liu

    2015-01-01

    We asked how repeated media reports on technological hazards influence an individual's risk perception. We looked for two contradictory effects, an increasing effect of repetition on perceived risk with the first few repetitions and a decreasing effect with later repetitions, leading to the inverted U-shaped pattern. In an experiment, we demonstrated the inverted U-shaped relationship between the repetition and perceived risk in the context of food risk. The finding broaden...

  5. Molecular characterization of Mycobacterium orygis isolates from wild animals of Nepal.

    Science.gov (United States)

    Thapa, Jeewan; Nakajima, Chie; Maharjan, Bhagwan; Poudell, Ajay; Suzuki, Yasuhiko

    2015-08-01

    Mycobacterium orygis, a new member of the Mycobacterium tuberculosis complex, was isolated from a captive spotted deer (Axis axis) and a blue bull (Boselaphus tragocamelus) in Nepal. Analyses by spoligotyping, mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing, region of difference and single nucleotide polymorphism of genes gyrB, mmpL6, TbD1, PPE55 and Rv2042c confirmed the isolates as M. orygis. Moreover, analyses by spoligotyping (SIT587) as well as MIRU-VNTR showed that the isolates shared a similar pattern with many reported isolates. From previous and the present studies, it can be inferred that South Asia is one of the endemic regions for M. orygis. Further investigation including a larger sample size and different host interaction will help to understand the ecology and epidemiology of M. orygis in Nepal.

  6. Don't Throw out the Baby with the Bathwater: Verbal Repetition, Mnemonics, and Active Learning

    Science.gov (United States)

    Saber, Jane Lee; Johnson, Richard D.

    2008-01-01

    The effectiveness of using verbal repetition and first-letter acronyms to teach a common marketing framework was examined in two experiments. In Experiment 1, 345 undergraduate students were exposed to the framework using one of four conditions: control, verbal repetition, acronym, and verbal repetition plus acronym in a traditional learning…

  7. Repetition suppression and multi-voxel pattern similarity differentially track implicit and explicit visual memory.

    Science.gov (United States)

    Ward, Emily J; Chun, Marvin M; Kuhl, Brice A

    2013-09-11

    Repeated exposure to a visual stimulus is associated with corresponding reductions in neural activity, particularly within visual cortical areas. It has been argued that this phenomenon of repetition suppression is related to increases in processing fluency or implicit memory. However, repetition of a visual stimulus can also be considered in terms of the similarity of the pattern of neural activity elicited at each exposure--a measure that has recently been linked to explicit memory. Despite the popularity of each of these measures, direct comparisons between the two have been limited, and the extent to which they differentially (or similarly) relate to behavioral measures of memory has not been clearly established. In the present study, we compared repetition suppression and pattern similarity as predictors of both implicit and explicit memory. Using functional magnetic resonance imaging, we scanned 20 participants while they viewed and categorized repeated presentations of scenes. Repetition priming (facilitated categorization across repetitions) was used as a measure of implicit memory, and subsequent scene recognition was used as a measure of explicit memory. We found that repetition priming was predicted by repetition suppression in prefrontal, parietal, and occipitotemporal regions; however, repetition priming was not predicted by pattern similarity. In contrast, subsequent explicit memory was predicted by pattern similarity (across repetitions) in some of the same occipitotemporal regions that exhibited a relationship between priming and repetition suppression; however, explicit memory was not related to repetition suppression. This striking double dissociation indicates that repetition suppression and pattern similarity differentially track implicit and explicit learning.

  8. Repetition suppression and repetition enhancement underlie auditory memory-trace formation in the human brain: an MEG study.

    Science.gov (United States)

    Recasens, Marc; Leung, Sumie; Grimm, Sabine; Nowak, Rafal; Escera, Carles

    2015-03-01

    The formation of echoic memory traces has traditionally been inferred from the enhanced responses to its deviations. The mismatch negativity (MMN), an auditory event-related potential (ERP) elicited between 100 and 250ms after sound deviation is an indirect index of regularity encoding that reflects a memory-based comparison process. Recently, repetition positivity (RP) has been described as a candidate ERP correlate of direct memory trace formation. RP consists of repetition suppression and enhancement effects occurring in different auditory components between 50 and 250ms after sound onset. However, the neuronal generators engaged in the encoding of repeated stimulus features have received little interest. This study intends to investigate the neuronal sources underlying the formation and strengthening of new memory traces by employing a roving-standard paradigm, where trains of different frequencies and different lengths are presented randomly. Source generators of repetition enhanced (RE) and suppressed (RS) activity were modeled using magnetoencephalography (MEG) in healthy subjects. Our results show that, in line with RP findings, N1m (~95-150ms) activity is suppressed with stimulus repetition. In addition, we observed the emergence of a sustained field (~230-270ms) that showed RE. Source analysis revealed neuronal generators of RS and RE located in both auditory and non-auditory areas, like the medial parietal cortex and frontal areas. The different timing and location of neural generators involved in RS and RE points to the existence of functionally separated mechanisms devoted to acoustic memory-trace formation in different auditory processing stages of the human brain. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. The development of interactive multimedia based on auditory, intellectually, repetition in repetition algorithm learning to increase learning outcome

    Science.gov (United States)

    Munir; Sutarno, H.; Aisyah, N. S.

    2018-05-01

    This research aims to find out how the development of interactive multimedia based on auditory, intellectually, and repetition can improve student learning outcomes. This interactive multimedia is developed through 5 stages. Analysis stages include the study of literature, questionnaire, interviews and observations. The design phase is done by the database design, flowchart, storyboards and repetition algorithm material while the development phase is done by the creation of web-based framework. Presentation material is adapted to the model of learning such as auditory, intellectually, repetition. Auditory points are obtained by recording the narrative material that presented by a variety of intellectual points. Multimedia as a product is validated by material and media experts. Implementation phase conducted on grade XI-TKJ2 SMKN 1 Garut. Based on index’s gain, an increasing of student learning outcomes in this study is 0.46 which is fair due to interest of student in using interactive multimedia. While the multimedia assessment earned 84.36% which is categorized as very well.

  10. Molecular structure and chromosome distribution of three repetitive DNA families in Anemone hortensis L. (Ranunculaceae).

    Science.gov (United States)

    Mlinarec, Jelena; Chester, Mike; Siljak-Yakovlev, Sonja; Papes, Drazena; Leitch, Andrew R; Besendorfer, Visnja

    2009-01-01

    The structure, abundance and location of repetitive DNA sequences on chromosomes can characterize the nature of higher plant genomes. Here we report on three new repeat DNA families isolated from Anemone hortensis L.; (i) AhTR1, a family of satellite DNA (stDNA) composed of a 554-561 bp long EcoRV monomer; (ii) AhTR2, a stDNA family composed of a 743 bp long HindIII monomer and; (iii) AhDR, a repeat family composed of a 945 bp long HindIII fragment that exhibits some sequence similarity to Ty3/gypsy-like retroelements. Fluorescence in-situ hybridization (FISH) to metaphase chromosomes of A. hortensis (2n = 16) revealed that both AhTR1 and AhTR2 sequences co-localized with DAPI-positive AT-rich heterochromatic regions. AhTR1 sequences occur at intercalary DAPI bands while AhTR2 sequences occur at 8-10 terminally located heterochromatic blocks. In contrast AhDR sequences are dispersed over all chromosomes as expected of a Ty3/gypsy-like element. AhTR2 and AhTR1 repeat families include polyA- and polyT-tracks, AT/TA-motifs and a pentanucleotide sequence (CAAAA) that may have consequences for chromatin packing and sequence homogeneity. AhTR2 repeats also contain TTTAGGG motifs and degenerate variants. We suggest that they arose by interspersion of telomeric repeats with subtelomeric repeats, before hybrid unit(s) amplified through the heterochromatic domain. The three repetitive DNA families together occupy approximately 10% of the A. hortensis genome. Comparative analyses of eight Anemone species revealed that the divergence of the A. hortensis genome was accompanied by considerable modification and/or amplification of repeats.

  11. Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

    DEFF Research Database (Denmark)

    Bonde, J. P.; Mikkelsen, S.; Andersen, JH

    2005-01-01

    for development of regional pain in repetitive work, stress symptoms would likely be on the causal path. AIMS: To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms. METHODS: In 1994-95, 2033 unskilled workers with continuous repetitive...... Profile Inventory. RESULTS: Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up. CONCLUSIONS......: The findings do not indicate that repetitive work is associated with stress symptoms, but small effects cannot be ruled out. Thus the results question the importance of mental stress mechanisms in the causation of regional pain related to repetitive work. However, the findings should be interpreted...

  12. Refining borders of genome-rearrangements including repetitions

    Directory of Open Access Journals (Sweden)

    JA Arjona-Medina

    2016-10-01

    Full Text Available Abstract Background DNA rearrangement events have been widely studied in comparative genomic for many years. The importance of these events resides not only in the study about relatedness among different species, but also to determine the mechanisms behind evolution. Although there are many methods to identify genome-rearrangements (GR, the refinement of their borders has become a huge challenge. Until now no accepted method exists to achieve accurate fine-tuning: i.e. the notion of breakpoint (BP is still an open issue, and despite repeated regions are vital to understand evolution they are not taken into account in most of the GR detection and refinement methods. Methods and results We propose a method to refine the borders of GR including repeated regions. Instead of removing these repetitions to facilitate computation, we take advantage of them using a consensus alignment sequence of the repeated region in between two blocks. Using the concept of identity vectors for Synteny Blocks (SB and repetitions, a Finite State Machine is designed to detect transition points in the difference between such vectors. The method does not force the BP to be a region or a point but depends on the alignment transitions within the SBs and repetitions. Conclusion The accurate definition of the borders of SB and repeated genomic regions and consequently the detection of BP might help to understand the evolutionary model of species. In this manuscript we present a new proposal for such a refinement. Features of the SBs borders and BPs are different and fit with what is expected. SBs with more diversity in annotations and BPs short and richer in DNA replication and stress response, which are strongly linked with rearrangements.

  13. A characterization of linearly repetitive cut and project sets

    Science.gov (United States)

    Haynes, Alan; Koivusalo, Henna; Walton, James

    2018-02-01

    For the development of a mathematical theory which can be used to rigorously investigate physical properties of quasicrystals, it is necessary to understand regularity of patterns in special classes of aperiodic point sets in Euclidean space. In one dimension, prototypical mathematical models for quasicrystals are provided by Sturmian sequences and by point sets generated by substitution rules. Regularity properties of such sets are well understood, thanks mostly to well known results by Morse and Hedlund, and physicists have used this understanding to study one dimensional random Schrödinger operators and lattice gas models. A key fact which plays an important role in these problems is the existence of a subadditive ergodic theorem, which is guaranteed when the corresponding point set is linearly repetitive. In this paper we extend the one-dimensional model to cut and project sets, which generalize Sturmian sequences in higher dimensions, and which are frequently used in mathematical and physical literature as models for higher dimensional quasicrystals. By using a combination of algebraic, geometric, and dynamical techniques, together with input from higher dimensional Diophantine approximation, we give a complete characterization of all linearly repetitive cut and project sets with cubical windows. We also prove that these are precisely the collection of such sets which satisfy subadditive ergodic theorems. The results are explicit enough to allow us to apply them to known classical models, and to construct linearly repetitive cut and project sets in all pairs of dimensions and codimensions in which they exist. Research supported by EPSRC grants EP/L001462, EP/J00149X, EP/M023540. HK also gratefully acknowledges the support of the Osk. Huttunen foundation.

  14. Relationship to carcinogenesis of repetitive low-dose radiation exposure

    International Nuclear Information System (INIS)

    Ootsuyama, Akira

    2016-01-01

    We studied the carcinogenic effects caused by repetitive irradiation at a low dose, which has received attention in recent years, and examined the experimental methods used to evaluate radiation-induced carcinogenesis. For this experiment, we selected a mouse with as few autochthonous cancers as possible. Skin cancer was selected as the target for analysis, because it is a rare cancer in mice. Beta-rays were selected as the radiation source. The advantage of using beta-rays is weaker penetration power into tissues, thus protecting organs, such as the digestive and hematogenous organs. The benefit of our experimental method is that only skin cancer requires monitoring, and it is possible to perform long-term experiments. The back skin of mice was exposed repetitively to beta-rays three times a week until the occurrence of cancer or death, and the dose per exposure ranged from 0.5 to 11.8 Gy. With the high-dose range (2.5-11.8 Gy), the latency period and carcinogenic rate were almost the same in each experimental group. When the dose was reduced to 1-1.5 Gy, the latency period increased, but the carcinogenic rate remained. When the dose was further reduced to 0.5 Gy, skin cancer never happened, even though we continued irradiation until death of the last mouse in this group. The lifespan of 0.5 Gy group mice was the same as that of the controls. We showed that the 0.5 Gy dose did not cause cancer, even in mice exposed repetitively throughout their life span, and thus refer to 0.5 Gy as the threshold-like dose. (author)

  15. High-repetition intra-cavity source of Compton radiation

    International Nuclear Information System (INIS)

    Pogorelsky, I; Polyanskiy, M; Agustsson, R; Campese, T; Murokh, A; Ovodenko, A; Shaftan, T

    2014-01-01

    We report our progress in developing a high-power Compton source for a diversity of applications ranging from university-scale compact x-ray light sources and metrology tools for EUV lithography, to high-brilliance gamma-sources for nuclear analysis. Our conceptual approach lies in multiplying the source’s repetition rate and increasing its average brightness by placing the Compton interaction point inside the optical cavity of an active laser. We discuss considerations in its design, our simulations, and tests of the laser’s cavity that confirm the feasibility of the proposed concept. (paper)

  16. Repetitive Transcranial Magnetic Stimulation in Patients with Hereditary Spastic Paraplegia

    Directory of Open Access Journals (Sweden)

    Mehmet Ağırman

    2011-06-01

    Full Text Available Hereditary spastic paraplegia (HSPP is a heterogeneous genetic disease characterized by progressive spasticity of lower extremities. Spasticity is a major cause of long-term disability in HSPP and significantly affects the functional life of patients. Repetitive transcranial magnetic stimulation (rTMS is widely used in diagnosis and treatment of many neurological and psychiatric diseases. Although the positive impacts of rTMS for spasticity have been reported, no study has been found on HSPP. We present two HSPP patients treated with low frequency rTMS (20 minutes at a frequency of 1 Hz (1200 pulses, for a period of 10 treatment sessions.

  17. Repetitive Transcranial Magnetic Stimulation in Patients with Hereditary Spastic Paraplegia

    Directory of Open Access Journals (Sweden)

    Mehmet Ağırman

    2011-06-01

    Full Text Available Hereditary spastic paraplegia (HSPP is a heterogeneous genetic disease characterized by progressive spasticity of lower extremities. Spasticity is a major cause of long-term disability in HSPP and significantly affects the functional life of patients. Repetitive transcranial magnetic stimulation (rTMS is widely used in diagnosis and treatment of many neurological and psychiatric diseases. Although the positive impacts of rTMS for spasticity have been reported, no study has been found on HSPP. We present two HSPP patients treated with low frequency rTMS (20 minutes at a frequency of 1 Hz (1200 pulses, for a period of 10 treatment sessions

  18. About the Infinite Repetition of Histories in Space

    Directory of Open Access Journals (Sweden)

    Manuel Alfonseca

    2014-08-01

    Full Text Available This paper analyzes two different proposals, one by Ellis and Brundrit, based on classical relativistic cosmology, the other by Garriga and Vilenkin, based on the DH interpretation of quantum mechanics, both concluding that, in an infinite universe, planets and beings must be repeated an infinite number of times. We point to possible shortcomings in these arguments. We conclude that the idea of an infinite repetition of histories in space cannot be considered strictly speaking a consequence of current physics and cosmology. Such ideas should be seen rather as examples of «ironic science» in the terminology of John Horgan.

  19. ARCA II - a new apparatus for fast, repetitive HPLC separations

    International Nuclear Information System (INIS)

    Schaedel, M.; Bruechle, W.; Jaeger, E.; Schimpf, E.; Kratz, J.V.; Scherer, U.W.; Zimmermann, H.P.

    1989-04-01

    The microcomputer controlled Automated Rapid Chemistry Apparatus, ARCA, is described in its newly designed version for the study of chemical properties of element 105 in aqueous solutions. This improved version, ARCA II, is adapted to the needs of fast and repetitive separations to be carried out in a chemically inert automated micro high performance liquid chromatography system. As an example, the separation of several group IIIB, IVB, and VB elements in the system triisooctylamine/hydrochloric acid within 30 s is demonstrated. Furthermore, a new method for the fast preparation of samples for α-particle spectroscopy by evaporation of the aqueous effluent with an intense light source is presented. (orig.)

  20. Design of a repetitively pulsed megajoule dense-plasma focus

    International Nuclear Information System (INIS)

    Zucker, O.; Bostick, W.; Gullickson, R.; Long, J.; Luce, J.; Sahlin, H.

    1975-01-01

    This report describes a 1 pulse per second, dense-plasma-focus (DPF) materials-testing device capable of delivering a minimum of 10 15 neutrons per pulse. Moderate scaling up from existing designs is shown to be sufficient to provide 2 x 10 13 neutrons/ cm 2 . s to a suitable target. The average power consumption, which has become a major issue due to the energy crisis, is analyzed with respect to other plasma devices and is shown to be highly favorable. Also discussed is a novel approach to capacitor-bank and switch design with respect to repetitive-pulse operation. (auth)

  1. Environmentally stable picosecond Yb fiber laser with low repetition rate

    Science.gov (United States)

    Baumgartl, M.; Abreu-Afonso, J.; Díez, A.; Rothhardt, M.; Limpert, J.; Tünnermann, A.

    2013-04-01

    A SESAM-mode-locked, all-polarization-maintaining Ytterbium fiber laser producing picosecond pulses with narrow spectral bandwidth is presented. A simple linear all-fiber cavity without dispersion compensation is realized using a uniform fiber Bragg grating (FBG). Different cavity lengths are investigated and repetition rates down to 0.7 MHz are obtained. Bandwidth and pulse duration of the output pulses are mainly determined by the choice of FBG. Pulses between 30 and 200 ps are generated employing different FBGs with bandwidths between 17 and 96 pm. The experimental results are in good agreement with numerical simulations. The laser holds great potential for simple amplification setups without pulse picking.

  2. Transcutaneous Auricular Vagus Nerve Stimulation with Concurrent Upper Limb Repetitive Task Practice for Poststroke Motor Recovery: A Pilot Study.

    Science.gov (United States)

    Redgrave, Jessica N; Moore, Lucy; Oyekunle, Tosin; Ebrahim, Maryam; Falidas, Konstantinos; Snowdon, Nicola; Ali, Ali; Majid, Arshad

    2018-03-23

    Invasive vagus nerve stimulation (VNS) has the potential to enhance the effects of physiotherapy for upper limb motor recovery after stroke. Noninvasive, transcutaneous auricular branch VNS (taVNS) may have similar benefits, but this has not been evaluated in stroke recovery. We sought to determine the feasibility of taVNS delivered alongside upper limb repetitive task-specific practice after stroke and its effects on a range of outcome measures evaluating limb function. Thirteen participants at more than 3 months postischemic stroke with residual upper limb dysfunction were recruited from the community of Sheffield, United Kingdom (October-December 2016). Participants underwent 18 × 1-hour sessions over 6 weeks in which they made 30-50 repetitions of 8-10 arm movements concurrently with taVNS (NEMOS; Cerbomed, Erlangen, Germany, 25 Hz, .1-millisecond pulse width) at maximum tolerated intensity (mA). An electrocardiogram and rehabilitation outcome scores were obtained at each visit. Qualitative interviews determined the acceptability of taVNS to participants. Median time after stroke was 1.16 years, and baseline median/interquartile range upper limb Fugl-Meyer (UFM) score was 63 (54.5-99.5). Participants attended 92% of the planned treatment sessions. Three participants reported side effects, mainly fatigue, but all performed mean of more than 300 arm repetitions per session with no serious adverse events. There was a significant change in the UFM score with a mean increase per participant of 17.1 points (standard deviation 7.8). taVNS is feasible and well-tolerated alongside upper limb repetitive movements in poststroke rehabilitation. The motor improvements observed justify a phase 2 trial in patients with residual arm weakness. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  3. Identification of an O-linked repetitive glycan chain of the polar flagellum flagellin of Azospirillum brasilense Sp7.

    Science.gov (United States)

    Belyakov, Alexei Ye; Burygin, Gennady L; Arbatsky, Nikolai P; Shashkov, Alexander S; Selivanov, Nikolai Yu; Matora, Larisa Yu; Knirel, Yuriy A; Shchyogolev, Sergei Yu

    2012-11-01

    This is the first report to have identified an O-linked repetitive glycan in bacterial flagellin, a structural protein of the flagellum. Studies by sugar analysis, Smith degradation, (1)H and (13)C NMR spectroscopy, and mass spectrometry showed that the glycan chains of the polar flagellum flagellin of the plant-growth-promoting rhizobacterium Azospirillum brasilense Sp7 are represented by a polysaccharide with a molecular mass of 7.7 kDa, which has a branched tetrasaccharide repeating unit of the following structure: Copyright © 2012. Published by Elsevier Ltd.

  4. Repetitive pulse accelerator technology for light ion inertial confinement fusion

    International Nuclear Information System (INIS)

    Buttram, M.T.

    1985-01-01

    Successful ignition of an inertial confinement fusion (ICF) pellet is calculated to require that several megajoules of energy be deposited in the pellet's centimeter-sized shell within 10 ns. This implies a driver power of several hundreds of terawatts and power density around 100 TW/cm 2 . The Sandia ICF approach is to deposit the energy with beams of 30 MV lithium ions. The first accelerator capable of producing these beams (PBFA II, 100 TW) will be used to study beam formation and target physics on a single pulse basis. To utilize this technology for power production, repetitive pulsing at rates that may be as high as 10 Hz will be required. This paper will overview the technologies being studied for a repetitively pulsed ICF accelerator. As presently conceived, power is supplied by rotating machinery providing 16 MJ in 1 ms. The generator output is transformed to 3 MV, then switched into a pulse compression system using laser triggered spark gaps. These must be synchronized to about 1 ns. Pulse compression is performed with saturable inductor switches, the output being 40 ns, 1.5 MV pulses. These are transformed to 30 MV in a self-magnetically insulated cavity adder structure. Space charge limited ion beams are drawn from anode plasmas with electron counter streaming being magnetically inhibited. The ions are ballistically focused into the entrances of guiding discharge channels for transport to the pellet. The status of component development from the prime power to the ion source will be reviewed

  5. Verbal behavior in Alzheimer's disease patients: Analysis of phrase repetition.

    Science.gov (United States)

    Cecato, Juliana Francisca; Martinellil, José Eduardo; Bartholomeu, Luana Luz; Basqueira, Ana Paula; Yassuda, Mônica Sanches; Aprahamian, Ivan

    2010-01-01

    Language problems in the elderly with AD are due to the fact that deterioration occurs not only in semantic memory, but in a group of cognitive factors, evidenced by a deficiency in search strategies for linguistic information. To evaluate phrase repetition in two cognitive tests, the MMSE and MoCA, in a group of Alzheimer disease patients (AD) and normal controls. A Cross-sectional study was conducted involving 20 patients who sought medical assistance at a geriatric institute in Jundiaí, São Paulo. The subjects underwent a detailed clinical examination and neuropsychometric evaluation. All subjects with AD met DSM-IV and NINCDS-ADRDA criteria. Ten patients received a diagnosis of AD and 10 were healthy subjects, forming the control group (CG). All participants correctly answered the phrase from the MMSE (phrase 1). The MoCA phrases (phrases 2 and 3) were correct in 80% and 90%, respectively in the CG and in 40% and 50%, respectively in the AD group. The MoCA test proved more effective in evaluating the echoic behavior in AD patients compared to the MMSE. The simpler phrase repetition task in the MMSE was found to be less sensitive in detecting mild language decline in AD patients.

  6. Identification of multiple modes of axisymmetric or circularly repetitive structures

    International Nuclear Information System (INIS)

    Kopff, P.

    1983-01-01

    The axisymmetric structures, or those composed with circularly repetitive elements, often display multiple modes, which are not easy to separate by modal identification of experimental responses. To be able to solve in situ some problems related to the vibrational behaviour of reactor vessels or other such huge structures, ELECTRICITY DE FRANCE developed a few years ago, experimental capabilities providing heavy harmonic driving forces, and elaborate data acquisition, signal processing and modal identification software, self-contained in an integrated mobile test facility. The modal analysis techniques we have developed with the LABORATOIRE DE MECANIQUE Appliquee of University of BESANCON (FRANCE) were especially suited for identification of multiple or separation of quasi-multiple modes, i.e. very close and strongly coupled resonances. Besides, the curve fitting methods involved, compute the same complex eigen-frequencies for all the vibration pick-ups, for better accuracy of the related eigen-vector components. Moreover, the latest extensions of these algorithms give us the means to deal with non-linear behaviour. The performances of these programs are drawn from some experimental results on axisymmetric or circularly repetitive structure, we tested in our laboratory to validate the computational hypothesis used in models for seismic responses of breeder reactor vessels. (orig.)

  7. Verbal behavior in Alzheimer disease patients: Analysis of phrase repetition

    Directory of Open Access Journals (Sweden)

    Juliana Francisca Cecato

    Full Text Available Abstract Language problems in the elderly with AD are due to the fact that deterioration occurs not only in semantic memory, but in a group of cognitive factors, evidenced by a deficiency in search strategies for linguistic information. Objectives: To evaluate phrase repetition in two cognitive tests, the MMSE and MoCA, in a group of Alzheimer disease patients (AD and normal controls. Methods: A Cross-sectional study was conducted involving 20 patients who sought medical assistance at a geriatric institute in Jundiaí, São Paulo. The subjects underwent a detailed clinical examination and neuropsychometric evaluation. All subjects with AD met DSM-IV and NINCDS-ADRDA criteria. Ten patients received a diagnosis of AD and 10 were healthy subjects, forming the control group (CG. Results: All participants correctly answered the phrase from the MMSE (phrase 1. The MoCA phrases (phrases 2 and 3 were correct in 80% and 90%, respectively in the CG and in 40% and 50%, respectively in the AD group. Conclusions: The MoCA test proved more effective in evaluating the echoic behavior in AD patients compared to the MMSE. The simpler phrase repetition task in the MMSE was found to be less sensitive in detecting mild language decline in AD patients.

  8. A repetitive probe for FISH analysis of bovine interphase nuclei

    Directory of Open Access Journals (Sweden)

    Cribiu Edmond

    2000-03-01

    Full Text Available Abstract The purpose of this study was to generate repetitive DNA sequence probes for the analysis of interphase nuclei by fluorescent in situ hybridisation (FISH. Such probes are useful for the diagnosis of chromosomal abnormalities in bovine preimplanted embryos. Of the seven probes (E1A, E4A, Ba, H1A, W18, W22, W5 that were generated and partially sequenced, five corresponded to previously described Bos taurus repetitive DNA (E1A, E4A, Ba, W18, W5, one probe (W22 shared no homology with other DNA sequences and one (H1A displayed a significant homology with Rattus norvegicus mRNA for secretin receptor transmembrane domain 3. Fluorescent in situ hybridisation was performed on metaphase bovine fibroblast cells and showed that five of the seven probes hybridised most centromeres (E1A, E4A, Ba, W18, W22, one labelled the arms of all chromosomes (W5 and the H1A probe was specific to three chromosomes (ch14, ch20, and ch25. Moreover, FISH with H1A resulted in interpretable signals on interphase nuclei in 88% of the cases, while the other probes yielded only dispersed overlapping signals.

  9. Rotated balance in humans due to repetitive rotational movement

    Science.gov (United States)

    Zakynthinaki, M. S.; Madera Milla, J.; López Diaz De Durana, A.; Cordente Martínez, C. A.; Rodríguez Romo, G.; Sillero Quintana, M.; Sampedro Molinuevo, J.

    2010-03-01

    We show how asymmetries in the movement patterns during the process of regaining balance after perturbation from quiet stance can be modeled by a set of coupled vector fields for the derivative with respect to time of the angles between the resultant ground reaction forces and the vertical in the anteroposterior and mediolateral directions. In our model, which is an adaption of the model of Stirling and Zakynthinaki (2004), the critical curve, defining the set of maximum angles one can lean to and still correct to regain balance, can be rotated and skewed so as to model the effects of a repetitive training of a rotational movement pattern. For the purposes of our study a rotation and a skew matrix is applied to the critical curve of the model. We present here a linear stability analysis of the modified model, as well as a fit of the model to experimental data of two characteristic "asymmetric" elite athletes and to a "symmetric" elite athlete for comparison. The new adapted model has many uses not just in sport but also in rehabilitation, as many work place injuries are caused by excessive repetition of unaligned and rotational movement patterns.

  10. New solid state opening switches for repetitive pulsed power technology

    Energy Technology Data Exchange (ETDEWEB)

    Lyubutin, S K; Mesyats, G A; Rukin, S N; Slovikovskii, B G; Turov, A M [Russian Academy of Sciences, Ekaterinburg (Russian Federation). Inst. of Electrophysics

    1997-12-31

    In 1991 the authors discovered a semiconductor opening switch (SOS) effect that occurs in p{sup +}-p-n-n{sup +} silicon structures at a current density of up to 60 kA/cm{sup 2}. This effect was used to develop high-power semiconductor opening switches in intermediate inductive storage circuits. The breaking power of the opening switches was as high as 5 GW, the interrupted current being up to 45 kA, reverse voltage up to 1 MV and the current interruption time between 10 and 60 ns. The opening switches were assembled from quantity-produced Russian-made rectifying diodes type SDL with hard recovery characteristic. On the basis of experimental and theoretical investigations of the SOS effect, new SOS diodes were designed and manufactured by the Electrophysical Institute. The paper gives basic parameters of the SOS diodes. The new diodes offer higher values of interrupted current and shorter times of current interruption together with a considerable increase in the energy switching efficiency. The new SOS diodes were used to develop repetitive all-solid-state pulsed generators with an output voltage of up to 250 kV, pulse repetition rate up to 5 kHz, and pulse duration between 10 and 30 ns. (author). 2 tabs., 3 figs., 4 refs.

  11. Application of repetitive pulsed power technology to chemical processing

    International Nuclear Information System (INIS)

    Kaye, R.J.; Hamil, R.

    1995-01-01

    The numerous sites of soil and water contaminated with organic chemicals present an urgent environmental concern that continues to grow. Electron and x-ray irradiation have been shown to be effective methods to destroy a wide spectrum of organic chemicals, nitrates, nitrites, and cyanide in water by breaking molecules to non-toxic products or entirely mineralizing the by-products to gas, water, and salts. Sandia National Laboratories is developing Repetitive High Energy Pulsed Power (RHEPP) technology capable of producing high average power, broad area electron or x-ray beams. The 300 kW RHEPP-II facility accelerates electrons to 2.5 MeV at 25 kA over 1,000 cm 2 in 60 ns pulses at repetition rates of over 100 Hz. Linking this modular treatment capability with the rapid optical-sensing diagnostics and neutral network characterization software algorithms will provide a Smart Waste Treatment (SWaT) system. Such a system would also be applicable for chemical manufacture and processing of industrial waste for reuse or disposal. This talk describes both the HREPP treatment capability and sensing technologies. Measurements of the propagated RHEPP-II beam and dose profiles are presented. Sensors and rapid detection software are discussed with application toward chemical treatment

  12. Evolution of repetitive explosive instabilities in space and time

    International Nuclear Information System (INIS)

    Wilhelmsson, H.

    1984-01-01

    A nonlinear rate equation describing nonlinear, explosive type interaction of waves in plasmas is studied, assuming that amplitude saturation occurs due to nonlinear frequency shifts. Emphasis is put on the space dependence of the solution caused by the assumption of a given initial amplitude distribution in space. An analysis is given of the problem of repetitive peaks governed by the nonlinear rate equation for the time development of the amplitudes of plasma waves and by a Lorentzian shape distribution of the initial amplitudes. For the one-dimensional case, the peaks developed by explosive instability move in the direction of lower initial amplitude values, and the speed and the repetition rate of the peaks are determined. The possible forms of equilibria for the nonlinear rate equation in the explosive case are also studied, including, in addition to the quadratic nonlinearity, diffusion and linear damping effects. A solution to the nonlinear rate equation including diffusion is also given for the case where the quadratic nonlinearity represents recombination. (Auth.)

  13. 200 ps FWHM and 100 MHz repetition rate ultrafast gated camera for optical medical functional imaging

    Science.gov (United States)

    Uhring, Wilfried; Poulet, Patrick; Hanselmann, Walter; Glazenborg, René; Zint, Virginie; Nouizi, Farouk; Dubois, Benoit; Hirschi, Werner

    2012-04-01

    The paper describes the realization of a complete optical imaging device to clinical applications like brain functional imaging by time-resolved, spectroscopic diffuse optical tomography. The entire instrument is assembled in a unique setup that includes a light source, an ultrafast time-gated intensified camera and all the electronic control units. The light source is composed of four near infrared laser diodes driven by a nanosecond electrical pulse generator working in a sequential mode at a repetition rate of 100 MHz. The resulting light pulses, at four wavelengths, are less than 80 ps FWHM. They are injected in a four-furcated optical fiber ended with a frontal light distributor to obtain a uniform illumination spot directed towards the head of the patient. Photons back-scattered by the subject are detected by the intensified CCD camera; there are resolved according to their time of flight inside the head. The very core of the intensified camera system is the image intensifier tube and its associated electrical pulse generator. The ultrafast generator produces 50 V pulses, at a repetition rate of 100 MHz and a width corresponding to the 200 ps requested gate. The photocathode and the Micro-Channel-Plate of the intensifier have been specially designed to enhance the electromagnetic wave propagation and reduce the power loss and heat that are prejudicial to the quality of the image. The whole instrumentation system is controlled by an FPGA based module. The timing of the light pulses and the photocathode gating is precisely adjustable with a step of 9 ps. All the acquisition parameters are configurable via software through an USB plug and the image data are transferred to a PC via an Ethernet link. The compactness of the device makes it a perfect device for bedside clinical applications.

  14. Effect of parallel magnetic field on repetitively unipolar nanosecond pulsed dielectric barrier discharge under different pulse repetition frequencies

    Science.gov (United States)

    Liu, Yidi; Yan, Huijie; Guo, Hongfei; Fan, Zhihui; Wang, Yuying; Wu, Yun; Ren, Chunsheng

    2018-03-01

    A magnetic field, with the direction parallel to the electric field, is applied to the repetitively unipolar positive nanosecond pulsed dielectric barrier discharge. The effect of the parallel magnetic field on the plasma generated between two parallel-plate electrodes in quiescent air is experimentally studied under different pulse repetition frequencies (PRFs). It is indicated that only the current pulse in the rising front of the voltage pulse occurs, and the value of the current is increased by the parallel magnetic field under different PRFs. The discharge uniformity is improved with the decrease in PRF, and this phenomenon is also observed in the discharge with the parallel magnetic field. By using the line-ratio technique of optical emission spectra, it is found that the average electron density and electron temperature under the considered PRFs are both increased when the parallel magnetic field is applied. The incremental degree of average electron density is basically the same under the considered PRFs, while the incremental degree of electron temperature under the higher-PRFs is larger than that under the lower-PRFs. All the above phenomena are explained by the effect of parallel magnetic field on diffusion and dissipation of electrons.

  15. Effects of modality and repetition in a continuous recognition memory task: Repetition has no effect on auditory recognition memory.

    Science.gov (United States)

    Amir Kassim, Azlina; Rehman, Rehan; Price, Jessica M

    2018-04-01

    Previous research has shown that auditory recognition memory is poorer compared to visual and cross-modal (visual and auditory) recognition memory. The effect of repetition on memory has been robust in showing improved performance. It is not clear, however, how auditory recognition memory compares to visual and cross-modal recognition memory following repetition. Participants performed a recognition memory task, making old/new discriminations to new stimuli, stimuli repeated for the first time after 4-7 intervening items (R1), or repeated for the second time after 36-39 intervening items (R2). Depending on the condition, participants were either exposed to visual stimuli (2D line drawings), auditory stimuli (spoken words), or cross-modal stimuli (pairs of images and associated spoken words). Results showed that unlike participants in the visual and cross-modal conditions, participants in the auditory recognition did not show improvements in performance on R2 trials compared to R1 trials. These findings have implications for pedagogical techniques in education, as well as for interventions and exercises aimed at boosting memory performance. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. High-repetition-rate hydrogen chamber: Preliminary studies; Chambre a hydrogene a haut taux de repetition: Etudes preliminaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1967-01-01

    This report is a conclusion to the tests realised with an experimental bubbles chamber in view to study the possibilities to increase the repetition rate. The more important parameters (the evolution of the bubbles, the expansion system) are considered in a theoretical way. Then the hardware is described. To end, experimental results are compared with the first evaluations. The calculations and the experimentation are against an oscillation system for the expansion. A system with a locking is to he considered. (authors) [French] Ce rapport est une conclusion aux essais realises avec une chambre a bulles experimentale en vue d'etudier les possibilites d'accroitre les taux de repetition. Les parametres les plus importants (evolution des bulles, mecanique de la detente) sont etudies par voie theorique. Puis l'appareillage est decrit. Enfin, les resultats experimentaux sont compares aux evaluations donnees au debut. Ces calculs et cette experimentation ne sont pas en faveur d'un systeme oscillant pour la detente et il faut envisager un systeme avec verrouillage. (auteurs)

  17. Relationship between the number of repetitions and selected percentages of one repetition maximum in free weight exercises in trained and untrained men.

    Science.gov (United States)

    Shimano, Tomoko; Kraemer, William J; Spiering, Barry A; Volek, Jeff S; Hatfield, Disa L; Silvestre, Ricardo; Vingren, Jakob L; Fragala, Maren S; Maresh, Carl M; Fleck, Steven J; Newton, Robert U; Spreuwenberg, Luuk P B; Häkkinen, Keijo

    2006-11-01

    Resistance exercise intensity is commonly prescribed as a percent of 1 repetition maximum (1RM). However, the relationship between percent 1RM and the number of repetitions allowed remains poorly studied, especially using free weight exercises. The purpose of this study was to determine the maximal number of repetitions that trained (T) and untrained (UT) men can perform during free weight exercises at various percentages of 1RM. Eight T and 8 UT men were tested for 1RM strength. Then, subjects performed 1 set to failure at 60, 80, and 90% of 1RM in the back squat, bench press, and arm curl in a randomized, balanced design. There was a significant (p squat than the bench press or arm curl at 60% 1RM for T and UT. At 80 and 90% 1RM, there were significant differences between the back squat and other exercises; however, differences were much less pronounced. No differences in number of repetitions performed at a given exercise intensity were noted between T and UT (except during bench press at 90% 1RM). In conclusion, the number of repetitions performed at a given percent of 1RM is influenced by the amount of muscle mass used during the exercise, as more repetitions can be performed during the back squat than either the bench press or arm curl. Training status of the individual has a minimal impact on the number of repetitions performed at relative exercise intensity.

  18. Two discharge modes of a repetitive nanosecond pulsed helium glow discharge under sub-atmospheric pressure in the repetition frequency range of 20 to 600 kHz

    Science.gov (United States)

    Kikuchi, Yusuke; Maegawa, Takuya; Otsubo, Akira; Nishimura, Yoshimi; Nagata, Masayoshi; Yatsuzuka, Mitsuyasu

    2018-05-01

    Two discharge modes, α and γ, of a repetitive nanosecond pulsed helium glow discharge at a gas pressure of 10 kPa in the repetition frequency range from 20 to 600 kHz are reported for the first time. The pulsed glow discharge is produced in a pair of parallel plate metal electrodes without insertion of dielectrics. The α mode discharge is volumetrically produced in the electrode gap at a low-repetition frequency, whereas the γ mode discharge is localized at the cathode surface at a high-repetition frequency. At high-repetition frequency, the time interval between voltage pulses is shorter than the lifetime of the afterglow produced by the preceding discharge. Then, the γ mode discharge is maintained by a large number of secondary electrons emitted from the cathode exposed to high-density ions and metastable helium atoms in the afterglow. In the α mode discharge with a low-repetition frequency operation, primary electrons due to gas ionization dominate the ionization process. Thus, a large discharge voltage is needed for the excitation of the α mode discharge. It is established that the bifurcation of α-γ discharge mode, accompanied by a decrease in the discharge voltage, occurs at the high-repetition frequency of ∼120 kHz.

  19. Optimality based repetitive controller design for track-following servo system of optical disk drives.

    Science.gov (United States)

    Chen, Wentao; Zhang, Weidong

    2009-10-01

    In an optical disk drive servo system, to attenuate the external periodic disturbances induced by inevitable disk eccentricity, repetitive control has been used successfully. The performance of a repetitive controller greatly depends on the bandwidth of the low-pass filter included in the repetitive controller. However, owing to the plant uncertainty and system stability, it is difficult to maximize the bandwidth of the low-pass filter. In this paper, we propose an optimality based repetitive controller design method for the track-following servo system with norm-bounded uncertainties. By embedding a lead compensator in the repetitive controller, both the system gain at periodic signal's harmonics and the bandwidth of the low-pass filter are greatly increased. The optimal values of the repetitive controller's parameters are obtained by solving two optimization problems. Simulation and experimental results are provided to illustrate the effectiveness of the proposed method.

  20. Functions of repetition in the discourse of elderly speakers: The role of prosody and gesture

    OpenAIRE

    Bolly, Catherine; Gerstenberg, Annette; 14th International Pragmatics Conference (IPra), Panel session "Age and language use"

    2015-01-01

    Cognitively speaking, repetition can work as a facilitator for both the planning and the understanding of spoken language. It can work as a cohesive and interactive device or, at a higher-level function of discourse, to engage in interaction by creating interpersonal involvement: repetition always conveys altered meaning, as it has to be re-interpreted by the interlocutor “in light of the accretion, juxtaposition, or expansion” (Tannen 2007: 62). Repetition is thus useful for the building of ...

  1. Nonword repetition in lexical decision: support for two opposing processes.

    Science.gov (United States)

    Wagenmakers, Eric-Jan; Zeelenberg, René; Steyvers, Mark; Shiffrin, Richard; Raaijmakers, Jeroen

    2004-10-01

    We tested and confirmed the hypothesis that the prior presentation of nonwords in lexical decision is the net result of two opposing processes: (1) a relatively fast inhibitory process based on global familiarity; and (2) a relatively slow facilitatory process based on the retrieval of specific episodic information. In three studies, we manipulated speed-stress to influence the balance between the two processes. Experiment 1 showed item-specific improvement for repeated nonwords in a standard "respond-when-ready" lexical decision task. Experiment 2 used a 400-ms deadline procedure and showed performance for nonwords to be unaffected by up to four prior presentations. In Experiment 3 we used a signal-to-respond procedure with variable time intervals and found negative repetition priming for repeated nonwords. These results can be accounted for by dual-process models of lexical decision.

  2. Repetitive Bunches from RF-Photo Gun Radiate Coherently

    CERN Document Server

    Van der Geer, C A J; Van der Geer, S B

    2004-01-01

    We consider to feed the laser wake field accelerator of the alpha-X project by a train of low charge pancake electron bunches to reduce undesired expansion due to space-charge forces. To this purpose the photo excitation laser of the rf-injector is split into a train of sub-pulses, such that each of the produced electron bunches falls into a successive ponderomotive well of the plasma accelerator. This way the total accelerated charge is not reduced. The repetitive photo gun can be tested, at low energy, by connecting it directly to the undulator and monitoring the radiation. The assertions are based on the results of new GPT simulations.

  3. Report on computation of repetitive hyperbaric-hypobaric decompression tables

    Science.gov (United States)

    Edel, P. O.

    1975-01-01

    The tables were constructed specifically for NASA's simulated weightlessness training program; they provide for 8 depth ranges covering depths from 7 to 47 FSW, with exposure times of 15 to 360 minutes. These tables were based up on an 8 compartment model using tissue half-time values of 5 to 360 minutes and Workmanline M-values for control of the decompression obligation resulting from hyperbaric exposures. Supersaturation ratios of 1.55:1 to 2:1 were used for control of ascents to altitude following such repetitive dives. Adequacy of the method and the resultant tables were determined in light of past experience with decompression involving hyperbaric-hypobaric interfaces in human exposures. Using these criteria, the method showed conformity with empirically determined values. In areas where a discrepancy existed, the tables would err in the direction of safety.

  4. [Repetitive impulse-associated behavioral disorders in Parkinson's disease].

    Science.gov (United States)

    Katzenschlager, R; Goerlich, K S; van Eimeren, T

    2012-12-01

    Parkinson's disease (PD) is associated with a number of behavioral disorders which may cause considerable social, professional or financial problems. Impulse control disorders (ICDs), such as pathological gambling, binge eating, compulsive shopping and hypersexuality occur in approximately 13-14% of PD patients. Further behavioral disorders are the dopamine dysregulation syndrome (DDS), a substance dependence characterized by craving for dopaminergic substances and punding (prolonged repetitive activities which are not goal-oriented).Treatment-related risk factors are dopamine agonists for ICDs and a high total dopaminergic dose for DDS and punding. Shared risk factors are young age at onset, impulsive personality traits, depression and possibly dyskinesia. At the neuronal level these behavioral disorders seem to be associated with changes in the reward system and dysfunction of the orbitofrontal cortex. The evidence level for management strategies is at present insufficient. For ICDs current clinical practice consists of discontinuation or reduction of dopamine agonists.

  5. Repetitive pulse accelerator technology for light ion inertial confinement fusion

    International Nuclear Information System (INIS)

    Buttram, M.T.

    1985-01-01

    This paper will overview the technologies being studied for a repetitively pulsed ICF accelerator. As presently conceived, power is supplied by rotating machinery providing 16 MJ in 1 ms. The generator output is transformed to 3 MV, then switched into a pulse compression system using laser triggered spark gaps. These must be synchronized to about 1 ns. Pulse compression is performed with saturable inductor switches, the output being 40 ns, 1.5 MV pulses. These are transformed to 30 MV in a self-magnetically insulated cavity adder structure. Space charge limited ion beams are drawn from anode plasmas with electron counter streaming being magnetically inhibited. The ions are ballistically focused into the entrances of guiding discharge channels for transport to the pellet. The status of component development from the prime power to the ion source will be reviewed

  6. High repetition rate driver circuit for modulation of injection lasers

    International Nuclear Information System (INIS)

    Dornan, B.R.; Goel, J.; Wolkstein, H.J.

    1981-01-01

    An injection laser modulator comprises a self-biased field effect transistor (FET) and an injection laser to provide a quiescent state during which lasing of the injection laser occurs in response to a high repetition rate signal of pulse coded modulation (pcm). The modulator is d.c. coupled to an input pulse source of pcm rendering it compatible with an input pulse referenced to ground and not being subject to voltage level shifting of the input pulse. The modulator circuit in its preferred and alternate embodiments provides various arrangements for high impedance input and low impedance output matching. In addition, means are provided for adjusting the bias of the FET as well as the bias of the injection laser

  7. A high repetition rate XUV seeding source for FLASH2

    International Nuclear Information System (INIS)

    Willner, Arik

    2012-05-01

    Improved performance of free-electron laser (FEL) light sources in terms of timing stability, pulse shape and spectral properties of the amplified FEL pulses is of interest in material science, the fields of ultrafast dynamics, biology, chemistry and even special branches in industry. A promising scheme for such an improvement is direct seeding with high harmonic generation (HHG) in a noble gas target. A free-electron laser seeded by an external extreme ultraviolet (XUV) source is planned for FLASH2 at DESY in Hamburg. The requirements for the XUV/soft X-ray source can be summarized as follows: A repetition rate of at least 100 kHz in a 10 Hz burst is needed at variable wavelengths from 10 to 40 nm and pulse energies of several nJ within a single laser harmonic. This application requires a laser amplifier system with exceptional parameters, mJ-level pulse energy, 10-15 fs pulse duration at 100 kHz (1 MHz) burst repetition rate. A new optical parametric chirped-pulse amplification (OPCPA) system is under development in order to meet these requirements, and very promising results have been achieved in the last three years. In parallel to this development, a new HHG concept is necessary to sustain high average power of the driving laser system and to generate harmonics with high conversion efficiencies. Currently, the highest conversion efficiency with HHG has been demonstrated using gas-filled capillary targets. For our application, only a free-jet target can be used for HHG, in order to overcome damage threshold limitations of HHG target optics at a high repetition rate. A novel dual-gas multijet gas target has been developed and first experiments show remarkable control of the degree of phase matching forming the basis for improved control of the harmonic photon flux and the XUV pulse characteristics. The basic idea behind the dual-gas concept is the insertion of matching zones in between multiple HHG sources. These matching sections are filled with hydrogen which

  8. A high repetition rate XUV seeding source for FLASH2

    Energy Technology Data Exchange (ETDEWEB)

    Willner, Arik

    2012-05-15

    Improved performance of free-electron laser (FEL) light sources in terms of timing stability, pulse shape and spectral properties of the amplified FEL pulses is of interest in material science, the fields of ultrafast dynamics, biology, chemistry and even special branches in industry. A promising scheme for such an improvement is direct seeding with high harmonic generation (HHG) in a noble gas target. A free-electron laser seeded by an external extreme ultraviolet (XUV) source is planned for FLASH2 at DESY in Hamburg. The requirements for the XUV/soft X-ray source can be summarized as follows: A repetition rate of at least 100 kHz in a 10 Hz burst is needed at variable wavelengths from 10 to 40 nm and pulse energies of several nJ within a single laser harmonic. This application requires a laser amplifier system with exceptional parameters, mJ-level pulse energy, 10-15 fs pulse duration at 100 kHz (1 MHz) burst repetition rate. A new optical parametric chirped-pulse amplification (OPCPA) system is under development in order to meet these requirements, and very promising results have been achieved in the last three years. In parallel to this development, a new HHG concept is necessary to sustain high average power of the driving laser system and to generate harmonics with high conversion efficiencies. Currently, the highest conversion efficiency with HHG has been demonstrated using gas-filled capillary targets. For our application, only a free-jet target can be used for HHG, in order to overcome damage threshold limitations of HHG target optics at a high repetition rate. A novel dual-gas multijet gas target has been developed and first experiments show remarkable control of the degree of phase matching forming the basis for improved control of the harmonic photon flux and the XUV pulse characteristics. The basic idea behind the dual-gas concept is the insertion of matching zones in between multiple HHG sources. These matching sections are filled with hydrogen which

  9. Intrinsic and extrinsic motivation for stereotypic and repetitive behavior.

    Science.gov (United States)

    Joosten, Annette V; Bundy, Anita C; Einfeld, Stewart L

    2009-03-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess anxiety as an intrinsic motivator. Rasch analysis of data from 279 MASs (74 children) revealed that the items formed two unidimensional scales. Anxiety was a more likely intrinsic motivator than sensory seeking for children with dual diagnoses; the reverse was true for children with intellectual disability only. Escape and gaining a tangible object were the most common extrinsic motivators for those with dual diagnoses and attention and escape for children with intellectual disability.

  10. Repetitive elements dynamics in cell identity programming, maintenance and disease

    KAUST Repository

    Bodega, Beatrice

    2014-12-01

    The days of \\'junk DNA\\' seem to be over. The rapid progress of genomics technologies has been unveiling unexpected mechanisms by which repetitive DNA and in particular transposable elements (TEs) have evolved, becoming key issues in understanding genome structure and function. Indeed, rather than \\'parasites\\', recent findings strongly suggest that TEs may have a positive function by contributing to tissue specific transcriptional programs, in particular as enhancer-like elements and/or modules for regulation of higher order chromatin structure. Further, it appears that during development and aging genomes experience several waves of TEs activation, and this contributes to individual genome shaping during lifetime. Interestingly, TEs activity is major target of epigenomic regulation. These findings are shedding new light on the genome-phenotype relationship and set the premises to help to explain complex disease manifestation, as consequence of TEs activity deregulation.

  11. Repetition blindness for natural images of objects with viewpoint changes

    Directory of Open Access Journals (Sweden)

    Stephane eBuffat

    2013-01-01

    Full Text Available When stimuli are repeated in a rapid serial visual presentation (RSVP, observers sometimes fail to report the second occurrence of a target. This phenomenon is referred to as repetition blindness (RB. We report an RSVP experiment with photographs in which we manipulated object viewpoints between the first and second occurrences of a target (0-, 45-, or 90-degree changes, and spatial frequency content. Natural images were spatially filtered to produce low, medium, or high spatial-frequency stimuli. RB was observed for all filtering conditions. Surprisingly, for full-spectrum images, RB increased significantly as the viewpoint reached 90 degrees. For filtered images, a similar pattern of results was found for all conditions except for medium spatial-frequency stimuli. These findings suggest that object recognition in RSVP are subtended by viewpoint-specific representations for all spatial frequencies except medium ones.

  12. Influence of Music Style and Rate on Repetitive Finger Tapping.

    Science.gov (United States)

    Stegemöller, Elizabeth L; Tatz, Joshua R; Warnecke, Alison; Hibbing, Paul; Bates, Brandon; Zaman, Andrew

    2018-03-09

    Auditory cues, including music, are commonly used in the treatment of persons with Parkinson's disease. Yet, how music style and movement rate modulate movement performance in persons with Parkinson's disease have been neglected and remain limited in healthy young populations. The purpose of this study was to determine how music style and movement rate influence movement performance in healthy young adults. Healthy participants were asked to perform repetitive finger movements at two pacing rates (70 and 140 beats per minute) for the following conditions: (a) a tone only, (b) activating music, and (c) relaxing music. Electromyography, movement kinematics, and variability were collected. Results revealed that the provision of music, regardless of style, reduced amplitude variability at both pacing rates. Intermovement interval was longer, and acceleration variability was reduced during both music conditions at the lower pacing rate only. These results may prove beneficial for designing therapeutic interventions for persons with Parkinson's disease.

  13. Repetitive fueling pellet injection in large helical device

    International Nuclear Information System (INIS)

    Yamada, H.; Sakamoto, R.; Viniar, I.; Oda, Y.; Kikuchi, K.; Lukin, A.; Skoblikov, S.; Umov, A.; Takaura, K.; Onozuka, M.; Kato, S.; Sudo, S.

    2003-01-01

    A repetitive pellet injector has been developed for investigation of fueling issues towards the steady-state operation in Large Helical Device (LHD). The goal of this approach is achievement of the plasma operation for longer than 1000 s. A principal technical element of the pellet injector is solidification of hydrogen and extrusion of a solid hydrogen rod through a cryogenic screw extruder cooled by Giffard-McMahon (GM) cryo-coolers. Continuous operation of more than 10000 pellet launches at 10 Hz has been demonstrated. The reliability of pellet launch exceeds 99%. The pellet mass and velocity, the consumption of propellant gas and quality of pellets have been successfully tested to fit the experimental requirement in LHD

  14. Repetitive fueling pellet injection in large helical device

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H. E-mail: hyamada@lhd.nifs.ac.jp; Sakamoto, R.; Viniar, I.; Oda, Y.; Kikuchi, K.; Lukin, A.; Skoblikov, S.; Umov, A.; Takaura, K.; Onozuka, M.; Kato, S.; Sudo, S

    2003-09-01

    A repetitive pellet injector has been developed for investigation of fueling issues towards the steady-state operation in Large Helical Device (LHD). The goal of this approach is achievement of the plasma operation for longer than 1000 s. A principal technical element of the pellet injector is solidification of hydrogen and extrusion of a solid hydrogen rod through a cryogenic screw extruder cooled by Giffard-McMahon (GM) cryo-coolers. Continuous operation of more than 10000 pellet launches at 10 Hz has been demonstrated. The reliability of pellet launch exceeds 99%. The pellet mass and velocity, the consumption of propellant gas and quality of pellets have been successfully tested to fit the experimental requirement in LHD.

  15. BANSHEE: High-voltage repetitively pulsed electron-beam driver

    International Nuclear Information System (INIS)

    VanHaaften, F.

    1992-01-01

    BANSHEE (Beam Accelerator for a New Source of High-Energy Electrons) this is a high-voltage modulator is used to produce a high-current relativistic electron beam for high-power microwave tube development. The goal of the BANSHEE research is first to achieve a voltage pulse of 700--750 kV with a 1-μs pulse width driving a load of ∼100 Ω, the pulse repetition frequency (PRF) of a few hertz. The ensuing goal is to increase the pulse amplitude to a level approaching 1 MV. We conducted tests using half the modulator with an output load of 200 Ω, up to a level of ∼650 kV at a PRF of 1 Hz and 525 kV at a PRF of 5 Hz. We then conducted additional testing using the complete system driving a load of ∼100 Ω

  16. Repetition rates in heavy ion beam driven fusion reactors

    Science.gov (United States)

    Peterson, Robert R.

    1986-01-01

    The limits on the cavity gas density required for beam propagation and condensation times for material vaporized by target explosions can determine the maximum repetition rate of Heavy Ion Beam (HIB) driven fusion reactors. If the ions are ballistically focused onto the target, the cavity gas must have a density below roughly 10-4 torr (3×1012 cm-3) at the time of propagation; other propagation schemes may allow densities as high as 1 torr or more. In some reactor designs, several kilograms of material may be vaporized off of the target chamber walls by the target generated x-rays, raising the average density in the cavity to 100 tor or more. A one-dimensional combined radiation hydrodynamics and vaporization and condensation computer code has been used to simulate the behavior of the vaporized material in the target chambers of HIB fusion reactors.

  17. Repetition rates in heavy ion beam driven fusion reactors

    International Nuclear Information System (INIS)

    Peterson, R.R.

    1986-01-01

    The limits on the cavity gas density required for beam propagation and condensation times for material vaporized by target explosions can determine the maximum repetition rate of Heavy Ion Beam (HIB) driven fusion reactors. If the ions are ballistically focused onto the target, the cavity gas must have a density below roughly 10 -4 torr (3 x 10 12 cm -3 ) at the time of propagation; other propagation schemes may allow densities as high as 1 torr or more. In some reactor designs, several kilograms of material may be vaporized off of the target chamber walls by the target generated x-rays, raising the average density in the cavity to 100 tor or more. A one-dimensional combined radiation hydrodynamics and vaporization and condensation computer code has been used to simulate the behavior of the vaporized material in the target chambers of HIB fusion reactors

  18. On the non-Poissonian repetition pattern of FRB121102

    Science.gov (United States)

    Oppermann, Niels; Yu, Hao-Ran; Pen, Ue-Li

    2018-04-01

    The Fast Radio Burst FRB121102 has been observed to repeat in an irregular fashion. Using published timing data of the observed bursts, we show that Poissonian statistics are not a good description of this random process. As an alternative, we suggest to describe the intervals between bursts with a Weibull distribution with a shape parameter smaller than one, which allows for the clustered nature of the bursts. We quantify the amount of clustering using the parameters of the Weibull distribution and discuss the consequences that it has for the detection probabilities of future observations and for the optimization of observing strategies. Allowing for this generalization, we find a mean repetition rate of r=5.7^{+3.0}_{-2.0} per day and index k=0.34^{+0.06}_{-0.05} for a correlation function ξ(t) = (t/t0)k - 1.

  19. Dose Measurements in a 20-J Repetitive Plasma Focus

    Science.gov (United States)

    Goudarzi, S.; Babaee, H.; Esmaeli, A.; Nasiri, A.; Mazandarani, A.

    2018-02-01

    In this article, the results of X-ray dose measurements executed using thermoluminescent dosimeters in experiments with a very small (20 J) repetitive plasma focus device named SORENA-1 are presented and analyzed. The working gas in these experiments was Argon. Also, pinch formation in experiments with this device has been observed. This device has been designed and constructed in Plasma and Nuclear Fusion Research School of Nuclear Science and Technology Research Institute of Iran. From these results, it is concluded that we can do experiments with this device using Ar as working gas all over the working days of year, and a good symmetry for measured dose around the device has been seen.

  20. Energy coupling to the plasma in repetitive nanosecond pulse discharges

    International Nuclear Information System (INIS)

    Adamovich, Igor V.; Nishihara, Munetake; Choi, Inchul; Uddi, Mruthunjaya; Lempert, Walter R.

    2009-01-01

    A new analytic quasi-one-dimensional model of energy coupling to nanosecond pulse discharge plasmas in plane-to-plane geometry has been developed. The use of a one-dimensional approach is based on images of repetitively pulsed nanosecond discharge plasmas in dry air demonstrating that the plasma remains diffuse and uniform on a nanosecond time scale over a wide range of pressures. The model provides analytic expressions for the time-dependent electric field and electron density in the plasma, electric field in the sheath, sheath boundary location, and coupled pulse energy. The analytic model predictions are in very good agreement with numerical calculations. The model demonstrates that (i) the energy coupled to the plasma during an individual nanosecond discharge pulse is controlled primarily by the capacitance of the dielectric layers and by the breakdown voltage and (ii) the pulse energy coupled to the plasma during a burst of nanosecond pulses decreases as a function of the pulse number in the burst. This occurs primarily because of plasma temperature rise and resultant reduction in breakdown voltage, such that the coupled pulse energy varies approximately proportionally to the number density. Analytic expression for coupled pulse energy scaling has been incorporated into the air plasma chemistry model, validated previously by comparing with atomic oxygen number density measurements in nanosecond pulse discharges. The results of kinetic modeling using the modified air plasma chemistry model are compared with time-resolved temperature measurements in a repetitively pulsed nanosecond discharge in air, by emission spectroscopy, and purely rotational coherent anti-Stokes Raman spectroscopy showing good agreement.

  1. Repetitive Pediatric Anesthesia in a Non-Hospital Setting

    International Nuclear Information System (INIS)

    Buchsbaum, Jeffrey C.; McMullen, Kevin P.; Douglas, James G.; Jackson, Jeffrey L.; Simoneaux, R. Victor; Hines, Matthew; Bratton, Jennifer; Kerstiens, John; Johnstone, Peter A.S.

    2013-01-01

    Purpose: Repetitive sedation/anesthesia (S/A) for children receiving fractionated radiation therapy requires induction and recovery daily for several weeks. In the vast majority of cases, this is accomplished in an academic center with direct access to pediatric faculty and facilities in case of an emergency. Proton radiation therapy centers are more frequently free-standing facilities at some distance from specialized pediatric care. This poses a potential dilemma in the case of children requiring anesthesia. Methods and Materials: The records of the Indiana University Health Proton Therapy Center were reviewed for patients requiring anesthesia during proton beam therapy (PBT) between June 1, 2008, and April 12, 2012. Results: A total of 138 children received daily anesthesia during this period. A median of 30 fractions (range, 1-49) was delivered over a median of 43 days (range, 1-74) for a total of 4045 sedation/anesthesia procedures. Three events (0.0074%) occurred, 1 fall from a gurney during anesthesia recovery and 2 aspiration events requiring emergency department evaluation. All 3 children did well. One aspiration patient needed admission to the hospital and mechanical ventilation support. The other patient returned the next day for treatment without issue. The patient who fell was not injured. No patient required cessation of therapy. Conclusions: This is the largest reported series of repetitive pediatric anesthesia in radiation therapy, and the only available data from the proton environment. Strict adherence to rigorous protocols and a well-trained team can safely deliver daily sedation/anesthesia in free-standing proton centers

  2. Environmental Enrichment Mitigates Deficits after Repetitive Mild Traumatic Brain Injury.

    Science.gov (United States)

    Liu, Xixia; Qiu, Jianhua; Alcon, Sasha; Hashim, Jumana; Meehan, William P; Mannix, Rebekah

    2017-08-15

    Although environmental enrichment has been shown to improve functional and histologic outcomes in pre-clinical moderate-to-severe traumatic brain injury (TBI), there are a paucity of pre-clinical data regarding enrichment strategies in the setting of repetitive mild traumatic brain injury (rmTBI). Given the vast numbers of athletes and those in the military who sustain rmTBI, the mounting evidence of the long-term and progressive sequelae of rmTBI, and the lack of targeted therapies to mitigate these sequelae, successful enrichment interventions in rmTBI could have large public health significance. Here, we evaluated enrichment strategies in an established pre-clinical rmTBI model. Seventy-one male C57BL/6 mice were randomized to two different housing conditions, environmental enrichment (EE) or normal condition (NC), then subjected to rmTBI injury (seven injuries in 9 days) or sham injury (anesthesia only). Functional outcomes in all four groups (NC-TBI, EE-TBI, NC-sham, and EE-sham) were assessed by motor, exploratory/anxiety, and mnemonic behavioral tests. At the synaptic level, N-methyl d-aspartate receptor (NMDAR) subunit expression of phosphorylated glutamate receptor 1 (GluR1), phosphorylated Ca 2+ /calmodulin-dependent protein kinase II (CaMKII), and calpain were evaluated by western blot. Compared to injured NC-TBI mice, EE-TBI mice had improved memory and decreased anxiety and exploratory activity post-injury. Treatment with enrichment also corresponded to normal NMDAR subunit expression, decreased GluR1 phosphorylation, decreased phosphorylated CaMKII, and normal calpain expression post-rmTBI. These data suggest that enrichment strategies may improve functional outcomes and mitigate synaptic changes post-rmTBI. Given that enrichment strategies are feasible in the clinical setting, particularly for athletes and soldiers for whom the risk of repetitive injury is greatest, these data suggest that clinical trials may be warranted.

  3. Electrophysiological signatures of phonological and semantic maintenance in sentence repetition.

    Science.gov (United States)

    Meltzer, Jed A; Kielar, Aneta; Panamsky, Lilia; Links, Kira A; Deschamps, Tiffany; Leigh, Rosie C

    2017-08-01

    Verbal short-term memory comprises resources for phonological rehearsal, which have been characterized anatomically, and for maintenance of semantic information, which are less understood. Sentence repetition tasks tap both processes interactively. To distinguish brain activity involved in phonological vs. semantic maintenance, we recorded magnetoencephalography during a sentence repetition task, incorporating three manipulations emphasizing one mechanism over the other. Participants heard sentences or word lists and attempted to repeat them verbatim after a 5-second delay. After MEG, participants completed a cued recall task testing how much they remembered of each sentence. Greater semantic engagement relative to phonological rehearsal was hypothesized for 1) sentences vs. word lists, 2) concrete vs. abstract sentences, and 3) well recalled vs. poorly recalled sentences. During auditory perception and the memory delay period, we found highly left-lateralized activation in the form of 8-30 Hz event-related desynchronization. Compared to abstract sentences, concrete sentences recruited posterior temporal cortex bilaterally, demonstrating a neural signature for the engagement of visual imagery in sentence maintenance. Maintenance of arbitrary word lists recruited right hemisphere dorsal regions, reflecting increased demands on phonological rehearsal. Sentences that were ultimately poorly recalled in the post-test also elicited extra right hemisphere activation when they were held in short-term memory, suggesting increased demands on phonological resources. Frontal midline theta oscillations also reflected phonological rather than semantic demand, being increased for word lists and poorly recalled sentences. These findings highlight distinct neural resources for phonological and semantic maintenance, with phonological maintenance associated with stronger oscillatory modulations. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Kolonizatsija Palestinõ prepjatstvujet miru / Jimmy Carter

    Index Scriptorium Estoniae

    Carter, Jimmy

    2006-01-01

    Iisraeli poliitika vastuolulisus, Palestiina koloniseerimine takistab rahulepingu sõlmimist, olenemata sellest, kes Palestiina riiki parajasti juhib. USA ekspresident Jimmy Carteri hinnang protsessidele regioonis

  5. The roles of stimulus repetition and hemispheric activation in visual half-field asymmetries.

    Science.gov (United States)

    Sullivan, K F; McKeever, W F

    1985-10-01

    Hardyck, Tzeng, and Wang (1978, Brain and Language, 5, 56-71) hypothesized that ample repetition of a small number of stimuli is required in order to obtain VHF differences in tachistoscopic tasks. Four experiments, with varied levels of repetition, were conducted to test this hypothesis. Three experiments utilized the general task of object-picture naming and one utilized a word-naming task. Naming latencies constituted the dependent measure. The results demonstrate that for the object-naming paradigm repetition is required for RVF superiority to emerge. Repetition was found to be unnecessary for RVF superiority in the word-naming paradigm, with repetition actually reducing RVF superiority. Experiment I suggested the possibility that RVF superiority developed for the second half of the trials as a function of practice or hemispheric activation, regardless of repetition level. Subsequent experiments, better designed to assess this possibility, clearly refuted it. It was concluded that the effect of repetition depends on the processing requirements of the task. We propose that, for tasks which can be processed efficiently by one hemisphere, the effect of repetition will be to reduce VHF asymmetries; but tasks requiring substantial processing by both hemispheres will show shifts to RVF superiority as a function of repetition.

  6. Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

    Science.gov (United States)

    Bonde, J P; Mikkelsen, S; Andersen, J H; Fallentin, N; Baelum, J; Svendsen, S W; Thomsen, J F; Frost, P; Kaergaard, A

    2005-01-01

    Pain in the neck and upper extremity is reported with high frequency in repetitive work. Mechanical overload of soft tissues seems a plausible mechanism, but psychological factors have received considerable attention during the past decade. If psychological factors are important for development of regional pain in repetitive work, stress symptoms would likely be on the causal path. To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms. In 1994-95, 2033 unskilled workers with continuous repetitive work and 813 workers with varied work were enrolled. Measures of repetitiveness and force requirements were quantified using video observations to obtain individual exposure estimates. Stress symptoms were recorded at baseline and after approximately one, two, and three years by the Setterlind Stress Profile Inventory. Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up. The findings do not indicate that repetitive work is associated with stress symptoms, but small effects cannot be ruled out. Thus the results question the importance of mental stress mechanisms in the causation of regional pain related to repetitive work. However, the findings should be interpreted with caution because the stress inventory has not been validated against a gold standard.

  7. Frequency Adaptive Repetitive Control of Grid-Tied Three-Phase PV Inverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current in the prese......Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current...

  8. Pulse repetition rate multiplication by Talbot effect in a coaxial fiber

    Science.gov (United States)

    Dhingra, Nikhil; Saxena, Geetika Jain; Anand, Jyoti; Sharma, Enakshi K.

    2018-03-01

    We use a coaxial fiber, which is a cylindrical coupled waveguide structure consisting of two concentric cores, the inner rod and an outer ring core as a first order dispersive media to achieve temporal Talbot effect for pulse repetition rate multiplication (PRRM) in high bit rate optical fiber communication. It is observed that for an input Gaussian pulse train with pulse width, 2τ0=1ps at a repetition rate of 40 Gbps (repetition period, T=25ps), an output repetition rate of 640 Gbps can be achieved without significant distortion at a length of 40.92 m.

  9. Identification of two new repetitive elements and chromosomal mapping of repetitive DNA sequences in the fish Gymnothorax unicolor (Anguilliformes: Muraenidae

    Directory of Open Access Journals (Sweden)

    E. Coluccia

    2011-05-01

    Full Text Available Muraenidae is a species-rich family, with relationships among genera and species and taxonomy that have not been completely clarified. Few cytogenetic studies have been conducted on this family, and all of them showed the same diploid chromosome number (2n=42 but with conspicuous karyotypic variation among species. The Mediterranean moray eel Gymnothorax unicolor was previously cytogenetically studied using classical techniques that allowed the characterization of its karyotype structure and the constitutive heterochromatin and argyrophilic nucleolar organizer regions (Ag-NORs distribution pattern. In the present study, we describe two new repetitive elements (called GuMboI and GuDdeI obtained from restricted genomic DNA of G. unicolor that were characterized by Southern blot and physically localized by in situ hybridization on metaphase chromosomes. As they are highly repetitive DNA sequences, they map in heterochromatic regions. However, while GuDdeI was localized in the centromeric regions, the GuMboI fraction was distributed on some centromeres and was co-localized with the nucleolus organizer region (NOR. Comparative analysis with other Mediterranean species such as Muraena helena pointed out that these DNA fractions are species-specific and could potentially be used for species discrimination. As a new contribution to the karyotype of this species, we found that the major ribosomal genes are localized on acrocentric chromosome 9 and that the telomeres of each chromosome are composed of a tandem repeat derived from a poly-TTAGGG DNA sequence, as it occurs in most vertebrate species. The results obtained add new information useful in comparative genomics at the chromosomal level and contribute to the cytogenetic knowledge regarding this fish family, which has not been extensively studied.

  10. Hemispheric Asymmetries in Repetition Enhancement and Suppression Effects in the Newborn Brain.

    Science.gov (United States)

    Bouchon, Camillia; Nazzi, Thierry; Gervain, Judit

    2015-01-01

    The repeated presentation of stimuli typically attenuates neural responses (repetition suppression) or, less commonly, increases them (repetition enhancement) when stimuli are highly complex, degraded or presented under noisy conditions. In adult functional neuroimaging research, these repetition effects are considered as neural correlates of habituation. The development and respective functional significance of these effects in infancy remain largely unknown. This study investigates repetition effects in newborns using functional near-infrared spectroscopy, and specifically the role of stimulus complexity in evoking a repetition enhancement vs. a repetition suppression response, following up on Gervain et al. (2008). In that study, abstract rule-learning was found at birth in cortical areas specific to speech processing, as evidenced by a left-lateralized repetition enhancement of the hemodynamic response to highly variable speech sequences conforming to a repetition-based ABB artificial grammar, but not to a random ABC grammar. Here, the same paradigm was used to investigate how simpler stimuli (12 different sequences per condition as opposed to 140), and simpler presentation conditions (blocked rather than interleaved) would influence repetition effects at birth. Results revealed that the two grammars elicited different dynamics in the two hemispheres. In left fronto-temporal areas, we reproduce the early perceptual discrimination of the two grammars, with ABB giving rise to a greater response at the beginning of the experiment than ABC. In addition, the ABC grammar evoked a repetition enhancement effect over time, whereas a stable response was found for the ABB grammar. Right fronto-temporal areas showed neither initial discrimination, nor change over time to either pattern. Taken together with Gervain et al. (2008), this is the first evidence that manipulating methodological factors influences the presence or absence of neural repetition enhancement effects in

  11. Hemispheric Asymmetries in Repetition Enhancement and Suppression Effects in the Newborn Brain.

    Directory of Open Access Journals (Sweden)

    Camillia Bouchon

    Full Text Available The repeated presentation of stimuli typically attenuates neural responses (repetition suppression or, less commonly, increases them (repetition enhancement when stimuli are highly complex, degraded or presented under noisy conditions. In adult functional neuroimaging research, these repetition effects are considered as neural correlates of habituation. The development and respective functional significance of these effects in infancy remain largely unknown.This study investigates repetition effects in newborns using functional near-infrared spectroscopy, and specifically the role of stimulus complexity in evoking a repetition enhancement vs. a repetition suppression response, following up on Gervain et al. (2008. In that study, abstract rule-learning was found at birth in cortical areas specific to speech processing, as evidenced by a left-lateralized repetition enhancement of the hemodynamic response to highly variable speech sequences conforming to a repetition-based ABB artificial grammar, but not to a random ABC grammar.Here, the same paradigm was used to investigate how simpler stimuli (12 different sequences per condition as opposed to 140, and simpler presentation conditions (blocked rather than interleaved would influence repetition effects at birth.Results revealed that the two grammars elicited different dynamics in the two hemispheres. In left fronto-temporal areas, we reproduce the early perceptual discrimination of the two grammars, with ABB giving rise to a greater response at the beginning of the experiment than ABC. In addition, the ABC grammar evoked a repetition enhancement effect over time, whereas a stable response was found for the ABB grammar. Right fronto-temporal areas showed neither initial discrimination, nor change over time to either pattern.Taken together with Gervain et al. (2008, this is the first evidence that manipulating methodological factors influences the presence or absence of neural repetition enhancement

  12. Translation of Syntactic Repetitions as Formal-Aesthetic Marker in Das Brot

    Directory of Open Access Journals (Sweden)

    Rosyidah

    2017-03-01

    Full Text Available Translating repetition as a formal-aesthetic marker in a literary text is a hard task and challenge for translators. The topic of this study is translation of syntactic repetition as formal-aesthetic marker in literary text. The problems examined include: (1 the syntactic repetitions in the source text and (2 the strategies to translate these repetitions carried out by the students. This is a case study with a qualitative approach which is aimed to describe the syntactic repetitions as formal aesthetic markers in the German short story Das Brot written by Wolfgang Borchert and to explain the strategies used by Indonesian students to translate the syntactic repetitions. The research data are repetitive sentences gained from the German short story and from the translated versions done by 60 students. The analysis was carried out interactively and sociosemiotically. The results show that there were repetitions at the sentence level including sentence parts, sentences and content repetition in the source text. The strategies used by the students to translate the repetitions of sentence part and sentence were exact preservation and modified preservation with reduction, implicitation and addition of extra words, avoidance with deletion, explicitation, implicitation, nominalization, and synonymy. In the meantime, content repetitions were translated using the strategy of exact preservation and preservation with modification by adding extra words and using role-based terms of address. Thus, the results lead to two new variations of modified preservation, namely preservation by adding extra words and by changing addressing terms and one new variation of avoidance that is explicitation.

  13. Repetitive Behavior in Rubinstein-Taybi Syndrome: Parallels with Autism Spectrum Phenomenology

    Science.gov (United States)

    Waite, Jane; Moss, Joanna; Beck, Sarah R.; Richards, Caroline; Nelson, Lisa; Arron, Kate; Burbidge, Cheryl; Berg, Katy; Oliver, Chris

    2015-01-01

    Syndrome specific repetitive behavior profiles have been described previously. A detailed profile is absent for Rubinstein-Taybi syndrome (RTS). The Repetitive Behaviour Questionnaire and Social Communication Questionnaire were completed for children and adults with RTS (N = 87), Fragile-X (N = 196) and Down (N = 132) syndromes, and individuals…

  14. High-speed repetitive pellet injector prototype for magnetic confinement fusion devices

    International Nuclear Information System (INIS)

    Frattolillo, A.; Gasparotto, M.; Migliori, S.; Angelone, G.; Baldarelli, M.; Scaramuzzi, F.; Ronci, G.; Reggiori, A.; Riva, G.; Carlevaro, R.; Daminelli, G.B.

    1992-01-01

    The design of a test facility aimed at demonstrating the feasibility of high-speed repetitive acceleration of solid D 2 pellets for fusion applications, developed in a collaboration between Oak Ridge National Laboratory and ENEA Frascati, is presented. The results of tests performed at the CNPM/CNR on the piston wear in a repetitively operating two-stage gun are also reported

  15. The Function of Repeating: The Relation between Word Class and Repetition Type in Developmental Stuttering

    Science.gov (United States)

    Buhr, Anthony P.; Jones, Robin M.; Conture, Edward G.; Kelly, Ellen M.

    2016-01-01

    Background: It is already known that preschool-age children who stutter (CWS) tend to stutter on function words at the beginning of sentences. It is also known that phonological errors potentially resulting in part-word repetitions tend to occur on content words. However, the precise relation between word class and repetition type in preschool-age…

  16. Functional dissociations in top-down control dependent neural repetition priming.

    NARCIS (Netherlands)

    Klaver, P.; Schnaidt, M.; Fell, J.; Ruhlmann, J.; Elger, C.E.; Fernandez, G.S.E.

    2007-01-01

    Little is known about the neural mechanisms underlying top-down control of repetition priming. Here, we use functional brain imaging to investigate these mechanisms. Study and repetition tasks used a natural/man-made forced choice task. In the study phase subjects were required to respond to either

  17. Target-to-Target Repetition Cost and Location Negative Priming Are Dissociable: Evidence for Different Mechanisms

    Science.gov (United States)

    Chao, Hsuan-Fu

    2011-01-01

    In a location-selection task, the repetition of a prior distractor location as the target location would slow down the response. This effect is termed the location negative priming (NP) effect. Recently, it has been demonstrated that repetition of a prior target location as the current target location would also slow down response. Because such…

  18. Changes of the Prefrontal EEG (Electroencephalogram) Activities According to the Repetition of Audio-Visual Learning.

    Science.gov (United States)

    Kim, Yong-Jin; Chang, Nam-Kee

    2001-01-01

    Investigates the changes of neuronal response according to a four time repetition of audio-visual learning. Obtains EEG data from the prefrontal (Fp1, Fp2) lobe from 20 subjects at the 8th grade level. Concludes that the habituation of neuronal response shows up in repetitive audio-visual learning and brain hemisphericity can be changed by…

  19. Genome-wide survey of repetitive DNA elements in the button mushroom Agaricus bisporus

    NARCIS (Netherlands)

    Foulongne-Oriol, M.; Murat, C.; Castanera, R.; Ramírez, L.; Sonnenberg, A.S.M.

    2013-01-01

    Repetitive DNA elements are ubiquitous constituents of eukaryotic genomes. The biological roles of these repetitive elements, supposed to impact genome organization and evolution, are not completely elucidated yet. The availability of whole genome sequence offers the opportunity to draw a picture of

  20. Repetition suppression in ventral visual cortex is diminished as a function of increasing autistic traits

    NARCIS (Netherlands)

    Ewbank, M.P.; Rhodes, G.; von dem Hagen, E.A.H.; Powell, T.E.; Bright, N.; Stoyanova, R.Z.; Baron-Cohen, S.; Calder, A.J.

    2015-01-01

    Repeated viewing of a stimulus causes a change in perceptual sensitivity, known as a visual aftereffect. Similarly, in neuroimaging, repetitions of the same stimulus result in a reduction in the neural response, known as repetition suppression (RS). Previous research shows that aftereffects for

  1. Cumulative Repetition Effects across Multiple Readings of a Word: Evidence from Eye Movements

    Science.gov (United States)

    Kamienkowski, Juan E.; Carbajal, M. Julia; Bianchi, Bruno; Sigman, Mariano; Shalom, Diego E.

    2018-01-01

    When a word is read more than once, reading time generally decreases in the successive occurrences. This Repetition Effect has been used to study word encoding and memory processes in a variety of experimental measures. We studied naturally occurring repetitions of words within normal texts (stories of around 3,000 words). Using linear mixed…

  2. Electrophysiological Repetition Effects in Persons with Mild Cognitive Impairment depend upon Working Memory Demand.

    Science.gov (United States)

    Broster, Lucas S; Jenkins, Shonna L; Holmes, Sarah D; Edwards, Matthew G; Jicha, Gregory A; Jiang, Yang

    2018-05-07

    Forms of implicit memory, including repetition effects, are preserved relative to explicit memory in clinical Alzheimer's disease. Consequently, cognitive interventions for persons with Alzheimer's disease have been developed that leverage this fact. However, despite the clinical robustness of behavioral repetition effects, altered neural mechanisms of repetition effects are studied as biomarkers of both clinical Alzheimer's disease and pre-morbid Alzheimer's changes in the brain. We hypothesized that the clinical preservation of behavioral repetition effects results in part from concurrent operation of discrete memory systems. We developed two experiments that included probes of emotional repetition effects differing in that one included an embedded working memory task. We found that neural repetition effects manifested in patients with amnestic mild cognitive impairment, the earliest form of clinical Alzheimer's disease, during emotional working memory tasks, but they did not manifest during the task that lacked the embedded working memory manipulation. Specifically, the working memory task evoked neural repetition effects in the P600 time-window, but the same neural mechanism was only minimally implicated in the task without a working memory component. We also found that group differences in behavioral repetition effects were smaller in the experiment with a working memory task. We suggest that cross-domain cognitive challenge can expose "defunct" neural capabilities of individuals with amnestic mild cognitive impairment. Copyright © 2018. Published by Elsevier Ltd.

  3. Relationship between Subtypes of Restricted and Repetitive Behaviors and Sleep Disturbance in Autism Spectrum Disorder

    Science.gov (United States)

    Hundley, Rachel J.; Shui, Amy; Malow, Beth A.

    2016-01-01

    We examined the association of two types of restricted and repetitive behaviors, repetitive sensory motor (RSM) and insistence on sameness (IS), with sleep problems in children with autism spectrum disorder (ASD). Participants included 532 children (aged 2-17) who participated in the Autism Speaks Autism Treatment Network research registry.…

  4. A Framework for Crosslinguistic Nonword Repetition Tests: Effects of Bilingualism and Socioeconomic Status on Children's Performance

    Science.gov (United States)

    Chiat, Shula; Polišenská, Kamila

    2016-01-01

    Purpose: As a recognized indicator of language impairment, nonword repetition has unique potential for distinguishing language impairment from difficulties due to limited experience and knowledge of a language. This study focused on a new Crosslinguistic Nonword Repetition framework, comprising 3 tests that vary the phonological characteristics of…

  5. Task Repetition Effects on L1 Use in EFL Child Task-Based Interaction

    Science.gov (United States)

    Azkarai, Agurtzane; García Mayo, María del Pilar

    2017-01-01

    Research has shown that tasks provide second language (L2) learners with many opportunities to learn the L2. Task repetition has been claimed to benefit L2 learning since familiarity with procedure and/or content gives learners the chance to focus on more specific aspects of language. Most research on task repetition has focused on adult…

  6. Investigating a tuberculosis cluster among Filipino health care workers in a low-incidence country.

    Science.gov (United States)

    Davidson, J A; Fulton, N; Thomas, H L; Lalor, M K; Zenner, D; Brown, T; Murphy, S; Anderson, L F

    2018-03-01

    Nearly 8% of adult tuberculosis (TB) cases in England, Wales and Northern Ireland (EW&NI) occur among health care workers (HCWs), the majority of whom are from high TB incidence countries. To determine if a TB cluster containing multiple HCWs was due to nosocomial transmission. A cluster of TB cases notified in EW&NI from 2009 to 2014, with indistinguishable 24-locus mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR) profiles, was identified through routine national cluster review. Cases were investigated to identify epidemiological links, and occupational health (OH) information was collected for HCW cases. To further discriminate strains, typing of eight additional loci was conducted. Of the 53 cases identified, 22 were HCWs. The majority (n = 43), including 21 HCWs, were born in the Philippines. Additional typing split the cluster into three subclusters and seven unique strains. No epidemiological links were identified beyond one household and a common residential area. HCWs in this cluster received no or inadequate OH assessment. The MIRU-VNTR profile of this cluster probably reflects common endemic strains circulating in the Philippines, with reactivation occurring in the UK. Furthermore, 32-locus typing showed that 24-locus MIRU-VNTR failed to distinguish strain diversity. The lack of OH assessment indicates that latent tuberculous infection could have been identified and treated, thereby preventing active cases from occurring.

  7. Genetic diversity of the Mycobacterium tuberculosis East African–Indian family in three tropical Asian countries

    Directory of Open Access Journals (Sweden)

    Yih-Yuan Chen

    2017-12-01

    Full Text Available Background: The Beijing lineage of Mycobacterium tuberculosis (MTB is the most predominant MTB strain in Asian countries and is spreading worldwide, however, the East African–Indian (EAI lineage is also particularly prevalent in many tropical Asian countries. The evolutionary relationships among MTB EAI isolates from Taiwan and those of tropical Asian countries remain unknown. Methods: The EAI strains collected from patients in Taiwan were analyzed using spacer oligonucleotide typing and mycobacterial interspersed repetitive unit–variable number of tandem repeats (MIRU-VNTR typing, and compared with published profiles from Cambodia and Singapore to investigate potential epidemiological linkages. Results: Among the three countries, the EAI lineage was most prevalent in Cambodia (60%; Singapore, 25.62%; and Taiwan, 21.85%, having also the highest rates of multidrug resistance and lowest rates of clustering of MTB isolates. We describe a convenient method using seven selected MIRU-VNTR loci for first-line typing to discriminate Beijing and EAI lineages. A potential epidemiological linkage in these tropical Asian countries is also discussed based on a minimum-spanning tree constructed using 24 MIRU-VNTR loci of MTB EAI strains. Conclusion: This study identified evolutionary relationships among MTB EAI isolates from Taiwan and those of two other tropical Asian countries, Cambodia and Singapore. Keywords: East African–Indian family, Mycobacterium tuberculosis, tropical Asian countries

  8. Interest of repetitive transcranial magnetic stimulation of the motor cortex in the management of refractory cancer pain in palliative care: Two case reports.

    Science.gov (United States)

    Nizard, Julien; Levesque, Amélie; Denis, Nathalie; de Chauvigny, Edwige; Lepeintre, Aurélie; Raoul, Sylvie; Labat, Jean-Jacques; Bulteau, Samuel; Maillard, Benoît; Buffenoir, Kevin; Potel, Gilles; Lefaucheur, Jean-Pascal; Nguyen, Jean Paul

    2015-06-01

    Non-drug treatments should be systematically associated to the medical analgesic treatment during the terminal phase of cancer. Patient 1, a 23-year-old woman, presented an adenocarcinoma of the rectum, with liver and lung metastases. Pain was initially treated by oral morphine and a combination of pregabalin and amitriptyline. Ketamine and intrathecal administration of morphine were both ineffective. Patient 2, a 69-year-old woman, presented a cutaneous T-cell lymphoma. She was admitted to the palliative care unit with mixed pain related to cutaneous lymphomatous infiltration. World Health Organization (WHO) step 3 analgesics had not been tolerated. Both patients received five consecutive 20-min sessions of repetitive transcranial magnetic stimulation to the right motor cortex. Patient 1 experienced a marked improvement of her pain over the days following the first repetitive transcranial magnetic stimulation session. Medical treatment was able to be rapidly decreased by about 50%, which restored an almost normal level of consciousness and lucidity. Patient 2's pain was also markedly decreased over the days following these five consecutive sessions, and repetitive transcranial magnetic stimulation also appeared to have had a beneficial effect on the patient's anxiety and mood. In the context of palliative care of cancer patients experiencing refractory pain that is difficult to control by the usual treatments, motor cortex repetitive transcranial magnetic stimulation, due to its noninvasive nature, can be used as an adjuvant therapy to improve various components of pain, including the emotional components. By reducing the doses of analgesics, repetitive transcranial magnetic stimulation decreases the severity of their adverse effects and improves the patient's quality of life. © The Author(s) 2015.

  9. Generation of µW level plateau harmonics at high repetition rate.

    Science.gov (United States)

    Hädrich, S; Krebs, M; Rothhardt, J; Carstens, H; Demmler, S; Limpert, J; Tünnermann, A

    2011-09-26

    The process of high harmonic generation allows for coherent transfer of infrared laser light to the extreme ultraviolet spectral range opening a variety of applications. The low conversion efficiency of this process calls for optimization or higher repetition rate intense ultrashort pulse lasers. Here we present state-of-the-art fiber laser systems for the generation of high harmonics up to 1 MHz repetition rate. We perform measurements of the average power with a calibrated spectrometer and achieved µW harmonics between 45 nm and 61 nm (H23-H17) at a repetition rate of 50 kHz. Additionally, we show the potential for few-cycle pulses at high average power and repetition rate that may enable water-window harmonics at unprecedented repetition rate. © 2011 Optical Society of America

  10. Human β satellite DNA: Genomic organization and sequence definition of a class of highly repetitive tandem DNA

    International Nuclear Information System (INIS)

    Waye, J.S.; Willard, H.F.

    1989-01-01

    The authors describe a class of human repetitive DNA, called β satellite, that, at a most fundamental level, exists as tandem arrays of diverged ∼68-base-pair monomer repeat units. The monomer units are organized as distinct subsets, each characterized by a multimeric higher-order repeat unit that is tandemly reiterated and represents a recent unit of amplification. They have cloned, characterized, and determined the sequence of two β satellite higher-order repeat units: one located on chromosome 9, the other on the acrocentric chromosomes (13, 14, 15, 21, and 22) and perhaps other sites in the genome. Analysis by pulsed-field gel electrophoresis reveals that these tandem arrays are localized in large domains that are marked by restriction fragment length polymorphisms. In total, β-satellite sequences comprise several million base pairs of DNA in the human genome. Analysis of this DNA family should permit insights into the nature of chromosome-specific and nonspecific modes of satellite DNA evolution and provide useful tools for probing the molecular organization and concerted evolution of the acrocentric chromosomes

  11. Auditory phonological priming in children and adults during word repetition

    Science.gov (United States)

    Cleary, Miranda; Schwartz, Richard G.

    2004-05-01

    Short-term auditory phonological priming effects involve changes in the speed with which words are processed by a listener as a function of recent exposure to other similar-sounding words. Activation of phonological/lexical representations appears to persist beyond the immediate offset of a word, influencing subsequent processing. Priming effects are commonly cited as demonstrating concurrent activation of word/phonological candidates during word identification. Phonological priming is controversial, the direction of effects (facilitating versus slowing) varying with the prime-target relationship. In adults, it has repeatedly been demonstrated, however, that hearing a prime word that rhymes with the following target word (ISI=50 ms) decreases the time necessary to initiate repetition of the target, relative to when the prime and target have no phonemic overlap. Activation of phonological representations in children has not typically been studied using this paradigm, auditory-word + picture-naming tasks being used instead. The present study employed an auditory phonological priming paradigm being developed for use with normal-hearing and hearing-impaired children. Initial results from normal-hearing adults replicate previous reports of faster naming times for targets following a rhyming prime word than for targets following a prime having no phonemes in common. Results from normal-hearing children will also be reported. [Work supported by NIH-NIDCD T32DC000039.

  12. Fusion neutron generation by high-repetitive target injection

    International Nuclear Information System (INIS)

    Kitagawa, Yoneyoshi

    2015-01-01

    Pellet injection and repetitive laser illumination are key technologies for realizing inertial fusion energy. The Graduate School for the Creation of New Photonics Industries, Hamamatsu Photonics K. K. and Toyota Motor Corporation demonstrate the pellet injection, counter laser beams' engagement and neutron generation. Deuterated polystyrene (CD) bead pellets, after free-falling for a distance of 18 cm at 1 Hz, are successfully engaged by two counter laser beams from a diode-pumped, ultra-intense laser HAMA. The laser energy, pulse duration, wavelength and the intensity are 0.63 J per beam, 104 fs, 811 nm and 4.7 x 10 18 W/cm 2 , respectively. The irradiated pellets produce D (D, n) 3 He-reacted neutrons with a maximum yield of 9.5 x 10 4 /4π sr/shot. A straight channel with 10 μm-diameter is found through the beads. The pellet size is 1 mm. The results indicate potentially useful technologies for the next step in realizing inertial fusion energy. The results are reviewed as well as some oversea activities. (author)

  13. LANGUAGE REPETITION AND SHORT-TERM MEMORY: AN INTEGRATIVE FRAMEWORK

    Directory of Open Access Journals (Sweden)

    Steve eMajerus

    2013-07-01

    Full Text Available Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the nonword-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury.

  14. Language repetition and short-term memory: an integrative framework.

    Science.gov (United States)

    Majerus, Steve

    2013-01-01

    Short-term maintenance of verbal information is a core factor of language repetition, especially when reproducing multiple or unfamiliar stimuli. Many models of language processing locate the verbal short-term maintenance function in the left posterior superior temporo-parietal area and its connections with the inferior frontal gyrus. However, research in the field of short-term memory has implicated bilateral fronto-parietal networks, involved in attention and serial order processing, as being critical for the maintenance and reproduction of verbal sequences. We present here an integrative framework aimed at bridging research in the language processing and short-term memory fields. This framework considers verbal short-term maintenance as an emergent function resulting from synchronized and integrated activation in dorsal and ventral language processing networks as well as fronto-parietal attention and serial order processing networks. To-be-maintained item representations are temporarily activated in the dorsal and ventral language processing networks, novel phoneme and word serial order information is proposed to be maintained via a right fronto-parietal serial order processing network, and activation in these different networks is proposed to be coordinated and maintained via a left fronto-parietal attention processing network. This framework provides new perspectives for our understanding of information maintenance at the non-word-, word- and sentence-level as well as of verbal maintenance deficits in case of brain injury.

  15. Variation and Repetition in the Spelling of Young Children

    Science.gov (United States)

    Treiman, Rebecca; Decker, Kristina; Kessler, Brett; Pollo, Tatiana

    2015-01-01

    A number of investigators have suggested that young children, even those do not yet represent the phonological forms of words in their spellings, tend to use different strings of letters for different words. However, empirical evidence that children possess a concept of between-word variation has been weak. In a study by Pollo, Kessler, and Treiman (2009), in fact, prephonological spellers were more likely to write different words in the same way than would be expected on the basis of chance, not less likely. In the present study, preschool-age prephonological and phonological spellers showed a tendency to repeat spellings and parts of spellings that they had recently used. However, even prephonological spellers (mean age 4 years, 8 months) showed more repetition when spelling the same word twice in succession than when spelling different words. The results suggest that children who have not yet learned to use writing to represent the sounds of speech show some knowledge that writing represents words and should thus vary to show differences between them. The results further suggest that in spelling, as in other domains, children have a tendency to repeat recent behaviors. PMID:25637713

  16. Use of repetitive transcranial magnetic stimulation for treatment in psychiatry.

    Science.gov (United States)

    Aleman, André

    2013-08-01

    The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory-verbal hallucinations in schizophrenia. The present review briefly describes the background of this novel treatment modality and summarizes evidence from clinical trials into the efficacy of rTMS for depression and hallucinations. Evidence for efficacy in depression is stronger than for hallucinations, although a number of studies have reported clinically relevant improvements for hallucinations too. Different stimulation parameters (frequency, duration, location of stimulation) are discussed. There is a paucity of research into other psychiatric disorders, but initial evidence suggests that rTMS may also hold promise for the treatment of negative symptoms in schizophrenia, obsessive compulsive disorder and post-traumatic stress disorder. It can be concluded that rTMS induces alterations in neural networks relevant for psychiatric disorders and that more research is needed to elucidate efficacy and underlying mechanisms of action.

  17. [Repetitive transcranial magnetic stimulation: A potential therapy for cognitive disorders?

    Science.gov (United States)

    Nouhaud, C; Sherrard, R M; Belmin, J

    2017-03-01

    Considering the limited effectiveness of drugs treatments in cognitive disorders, the emergence of noninvasive techniques to modify brain function is very interesting. Among these techniques, repetitive transcranial magnetic stimulation (rTMS) can modulate cortical excitability and have potential therapeutic effects on cognition and behaviour. These effects are due to physiological modifications in the stimulated cortical tissue and their associated circuits, which depend on the parameters of stimulation. The objective of this article is to specify current knowledge and efficacy of rTMS in cognitive disorders. Previous studies found very encouraging results with significant improvement of higher brain functions. Nevertheless, these few studies have limits: a few patients were enrolled, the lack of control of the mechanisms of action by brain imaging, insufficiently formalized technique and variability of cognitive tests. It is therefore necessary to perform more studies, which identify statistical significant improvement and to specify underlying mechanisms of action and the parameters of use of the rTMS to offer rTMS as a routine therapy for cognitive dysfunction. Copyright © 2016 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  18. Improved discrimination of visual stimuli following repetitive transcranial magnetic stimulation.

    Directory of Open Access Journals (Sweden)

    Michael L Waterston

    Full Text Available BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS at certain frequencies increases thresholds for motor-evoked potentials and phosphenes following stimulation of cortex. Consequently rTMS is often assumed to introduce a "virtual lesion" in stimulated brain regions, with correspondingly diminished behavioral performance. METHODOLOGY/PRINCIPAL FINDINGS: Here we investigated the effects of rTMS to visual cortex on subjects' ability to perform visual psychophysical tasks. Contrary to expectations of a visual deficit, we find that rTMS often improves the discrimination of visual features. For coarse orientation tasks, discrimination of a static stimulus improved consistently following theta-burst stimulation of the occipital lobe. Using a reaction-time task, we found that these improvements occurred throughout the visual field and lasted beyond one hour post-rTMS. Low-frequency (1 Hz stimulation yielded similar improvements. In contrast, we did not find consistent effects of rTMS on performance in a fine orientation discrimination task. CONCLUSIONS/SIGNIFICANCE: Overall our results suggest that rTMS generally improves or has no effect on visual acuity, with the nature of the effect depending on the type of stimulation and the task. We interpret our results in the context of an ideal-observer model of visual perception.

  19. Combinatorics on words Christoffel words and repetitions in words

    CERN Document Server

    Berstel, Jean; Reutenauer, Christophe; Saliola, Franco V

    2008-01-01

    The two parts of this text are based on two series of lectures delivered by Jean Berstel and Christophe Reutenauer in March 2007 at the Centre de Recherches Mathématiques, Montréal, Canada. Part I represents the first modern and comprehensive exposition of the theory of Christoffel words. Part II presents numerous combinatorial and algorithmic aspects of repetition-free words stemming from the work of Axel Thue-a pioneer in the theory of combinatorics on words. A beginner to the theory of combinatorics on words will be motivated by the numerous examples, and the large variety of exercises, which make the book unique at this level of exposition. The clean and streamlined exposition and the extensive bibliography will also be appreciated. After reading this book, beginners should be ready to read modern research papers in this rapidly growing field and contribute their own research to its development. Experienced readers will be interested in the finitary approach to Sturmian words that Christoffel words offe...

  20. Embryotoxicity following repetitive maternal exposure to scorpion venom

    Directory of Open Access Journals (Sweden)

    BN Hmed

    2012-01-01

    Full Text Available Although it is a frequent accident in a few countries, scorpion envenomation during pregnancy remains scarcely studied. In the present study, the effects of repetitive maternal exposure to Buthus occitanus tunetanus venom are investigated and its possible embryotoxic consequences on rats. Primigravid rats received a daily intraperitoneal dose of 1 mL/kg of saline solution or 300 µg/kg of crude scorpion venom, from the 7th to the 13th day of gestation. On the 21st day, the animals were deeply anesthetized using diethyl-ether. Then, blood was collected for chemical parameter analysis. Following euthanasia, morphometric measurements were carried out. The results showed a significant increase in maternal heart and lung absolute weights following venom treatment. However, the mean placental weight per rat was significantly diminished. Furthermore, blood urea concentration was higher in exposed rats (6.97 ± 0.62 mmol/L than in those receiving saline solution (4.94 ± 0.90 mmol/L. Many organs of venom-treated rat fetuses (brain, liver, kidney and spleen were smaller than those of controls. On the contrary, fetal lungs were significantly heavier in fetuses exposed to venom (3.2 ± 0.4 g than in the others (3.0 ± 0.2 g. Subcutaneous blood clots, microphthalmia and total body and tail shortening were also observed in venom-treated fetuses. It is concluded that scorpion envenomation during pregnancy potentially causes intrauterine fetal alterations and growth impairment.

  1. Repetitive transcranial magnetic stimulator with controllable pulse parameters

    Science.gov (United States)

    Peterchev, Angel V.; Murphy, David L.; Lisanby, Sarah H.

    2011-06-01

    The characteristics of transcranial magnetic stimulation (TMS) pulses influence the physiological effect of TMS. However, available TMS devices allow very limited adjustment of the pulse parameters. We describe a novel TMS device that uses a circuit topology incorporating two energy storage capacitors and two insulated-gate bipolar transistor (IGBT) modules to generate near-rectangular electric field pulses with adjustable number, polarity, duration, and amplitude of the pulse phases. This controllable pulse parameter TMS (cTMS) device can induce electric field pulses with phase widths of 10-310 µs and positive/negative phase amplitude ratio of 1-56. Compared to conventional monophasic and biphasic TMS, cTMS reduces energy dissipation up to 82% and 57% and decreases coil heating up to 33% and 41%, respectively. We demonstrate repetitive TMS trains of 3000 pulses at frequencies up to 50 Hz with electric field pulse amplitude and width variability less than the measurement resolution (1.7% and 1%, respectively). Offering flexible pulse parameter adjustment and reduced power consumption and coil heating, cTMS enhances existing TMS paradigms, enables novel research applications and could lead to clinical applications with potentially enhanced potency.

  2. Unraveling the cellular and molecular mechanisms of repetitive magnetic stimulation

    Directory of Open Access Journals (Sweden)

    Florian eMüller-Dahlhaus

    2013-12-01

    Full Text Available Despite numerous clinical studies, which have investigated the therapeutic potential of repetitive transcranial magnetic stimulation (rTMS in various brain diseases, our knowledge of the cellular and molecular mechanisms underlying rTMS-based therapies remains limited. Thus, a deeper understanding of rTMS-induced neural plasticity is required to optimize current treatment protocols. Studies in small animals or appropriate in vitro preparations (including models of brain diseases provide highly useful experimental approaches in this context. State-of-the-art electrophysiological and live-cell imaging techniques that are well established in basic neuroscience can help answering some of the major questions in the field, such as (i which neural structures are activated during TMS, (ii how does rTMS induce Hebbian plasticity, and (iii are other forms of plasticity (e.g., metaplasticity, structural plasticity induced by rTMS? We argue that data gained from these studies will support the development of more effective and specific applications of rTMS in clinical practice.

  3. Left prefrontal repetitive transcranial magnetic stimulation in schizophrenia.

    Science.gov (United States)

    Holi, Matti M; Eronen, Markku; Toivonen, Kari; Toivonen, Päivi; Marttunen, Mauri; Naukkarinen, Hannu

    2004-01-01

    In a double-blind, controlled study, we examined the therapeutic effects of high-frequency left prefrontal repetitive transcranial magnetic stimulation (rTMS) on schizophrenia symptoms. A total of 22 chronic hospitalized schizophrenia patients were randomly assigned to 2 weeks (10 sessions) of real or sham rTMS. rTMS was given with the following parameters: 20 trains of 5-second 10-Hz stimulation at 100 percent motor threshold, 30 seconds apart. Effects on positive and negative symptoms, self-reported symptoms, rough neuropsychological functioning, and hormones were assessed. Although there was a significant improvement in both groups in most of the symptom measures, no real differences were found between the groups. A decrease of more than 20 percent in the total PANSS score was found in 7 control subjects but only 1 subject from the real rTMS group. There was no change in hormone levels or neuropsychological functioning, measured by the MMSE, in either group. Left prefrontal rTMS (with the used parameters) seems to produce a significant nonspecific effect of the treatment procedure but no therapeutic effect in the most chronic and severely ill schizophrenia patients.

  4. Exploring the repetition bias in voluntary task switching.

    Science.gov (United States)

    Mittelstädt, Victor; Dignath, David; Schmidt-Ott, Magdalena; Kiesel, Andrea

    2018-01-01

    In the voluntary task-switching paradigm, participants are required to randomly select tasks. We reasoned that the consistent finding of a repetition bias (i.e., participants repeat tasks more often than expected by chance) reflects reasonable adaptive task selection behavior to balance the goal of random task selection with the goals to minimize the time and effort for task performance. We conducted two experiments in which participants were provided with variable amount of preview for the non-chosen task stimuli (i.e., potential switch stimuli). We assumed that switch stimuli would initiate some pre-processing resulting in improved performance in switch trials. Results showed that reduced switch costs due to extra-preview in advance of each trial were accompanied by more task switches. This finding is in line with the characteristics of rational adaptive behavior. However, participants were not biased to switch tasks more often than chance despite large switch benefits. We suggest that participants might avoid effortful additional control processes that modulate the effects of preview on task performance and task choice.

  5. Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders: A meta-analysis.

    Science.gov (United States)

    Zhang, Yingli; Liang, Wei; Yang, Shichang; Dai, Ping; Shen, Lijuan; Wang, Changhong

    2013-10-05

    This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hallucination of patients with schizophrenia spectrum disorders. Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Controlled Trials databases from January 1985 to May 2012. Key words were "transcranial magnetic stimulation", "TMS", "repetitive transcranial magnetic stimulation", and "hallucination". Selected studies were randomized controlled trials assessing therapeutic efficacy of repetitive transcranial magnetic stimulation for hallucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hallucination in schizophrenia spectrum disorders. Control groups received sham stimulation. The primary outcome was total scores of Auditory Hallucinations Rating Scale, Auditory Hallucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hallucination item, and Hallucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. All data were completely effective, involving 398 patients. Overall mean weighted effect size for repetitive transcranial magnetic stimulation versus sham stimulation was statistically significant (MD = -0.42, 95%CI: -0.64 to -0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%CI: 1.39 to 6.24, P = 0.005). No significant differences were found between active repetitive transcranial magnetic stimulation and sham stimulation for

  6. A clinical repetitive transcranial magnetic stimulation service in Australia: 6 years on.

    Science.gov (United States)

    Galletly, Cherrie A; Clarke, Patrick; Carnell, Benjamin L; Gill, Shane

    2015-11-01

    There is considerable research evidence for the effectiveness of repetitive transcranial magnetic stimulation in the treatment of depression. However, there is little information about its acceptability and outcomes in clinical settings. This naturalistic study reports on a clinical repetitive transcranial magnetic stimulation service that has been running in Adelaide, South Australia (SA), for 6 years. During this time, 214 complete acute courses were provided to patients with treatment-resistant Major Depressive Disorder. Patients received either sequential bilateral or right unilateral repetitive transcranial magnetic stimulation treatment involving either 18 or 20 sessions given over 6 or 4 weeks respectively. Data included patient demographic details, duration of depression, and medication at the beginning of their repetitive transcranial magnetic stimulation course. The Hamilton Depression Rating Scale was used to assess response to repetitive transcranial magnetic stimulation. Of those undergoing a first-time acute treatment course of repetitive transcranial magnetic stimulation (N = 167), 28% achieved remission, while a further 12% met the criteria for a response to treatment. Most patients (N = 123, 77%) had previously been treated with five or more antidepressant medications, and 77 (47%) had previously received electroconvulsive therapy. Referral rates remained high over the 6 years, indicating acceptance of the treatment by referring psychiatrists. There were no significant adverse events, and the treatment was generally well tolerated. In all, 41 patients (25%) had a second course of repetitive transcranial magnetic stimulation and 6 (4%) patients had a third course; 21 patients subsequently received maintenance repetitive transcranial magnetic stimulation. This naturalistic study showed that repetitive transcranial magnetic stimulation was well accepted by both psychiatrists and patients, and has good efficacy and safety. Furthermore

  7. Characterization and distribution of repetitive elements in association with genes in the human genome.

    Science.gov (United States)

    Liang, Kai-Chiang; Tseng, Joseph T; Tsai, Shaw-Jenq; Sun, H Sunny

    2015-08-01

    Repetitive elements constitute more than 50% of the human genome. Recent studies implied that the complexity of living organisms is not just a direct outcome of a number of coding sequences; the repetitive elements, which do not encode proteins, may also play a significant role. Though scattered studies showed that repetitive elements in the regulatory regions of a gene control gene expression, no systematic survey has been done to report the characterization and distribution of various types of these repetitive elements in the human genome. Sequences from 5' and 3' untranslated regions and upstream and downstream of a gene were downloaded from the Ensembl database. The repetitive elements in the neighboring of each gene were identified and classified using cross-matching implemented in the RepeatMasker. The annotation and distribution of distinct classes of repetitive elements associated with individual gene were collected to characterize genes in association with different types of repetitive elements using systems biology program. We identified a total of 1,068,400 repetitive elements which belong to 37-class families and 1235 subclasses that are associated with 33,761 genes and 57,365 transcripts. In addition, we found that the tandem repeats preferentially locate proximal to the transcription start site (TSS) of genes and the major function of these genes are involved in developmental processes. On the other hand, interspersed repetitive elements showed a tendency to be accumulated at distal region from the TSS and the function of interspersed repeat-containing genes took part in the catabolic/metabolic processes. Results from the distribution analysis were collected and used to construct a gene-based repetitive element database (GBRED; http://www.binfo.ncku.edu.tw/GBRED/index.html). A user-friendly web interface was designed to provide the information of repetitive elements associated with any particular gene(s). This is the first study focusing on the gene

  8. Use of percentile rank sum method in identifying repetitive high occupational radiation dose jobs in a nuclear power plant

    International Nuclear Information System (INIS)

    Cho, Y.H.; Ko, H.S.; Kim, S.H.; Kang, C.S.; Moon, J.H.; Kim, K.D.

    2004-01-01

    The cost-effective reduction of occupational radiation dose (ORD) at a nuclear power plant could not be achieved without going through an extensive analysis of accumulated ORD data of existing plants. Through the data analysis, it is required to identify what are the jobs of repetitive high ORD at the nuclear power plant. In general the point value method commonly used, over-estimates the role of mean and median values to identify the high ORD jobs which can lead to misjudgment. In this study, Percentile Rank Sum Method (PRSM) is proposed to identify repetitive high ORD jobs, which is based on non-parametric statistical theory. As a case study, the method is applied to ORD data of maintenance and repair jobs at Kori units 3 and 4 that are pressurized water reactors with 950 MWe capacity and have been operated since 1986 and 1987, respectively in Korea. The results were verified and validated, and PRSM has been demonstrated to be an efficient method of analyzing the data. (authors)

  9. Repetitive Solid Spherical Pellet Injection and Irradiation toward the Repetitive-mode Fast-Ignition Fusion miniReactor CANDY

    International Nuclear Information System (INIS)

    HANAYAMA, Ryohei; KOMEDA, Osamu; NISHIMURA, Yasuhiko; MORI, Yoshitaka; ISHII, Katsuhiro; NAKAYAMA, Suisei; OKIHARA, Shinichiro; FUJITA, Kazuhisa; SEKINE, Takashi; SATO, Nakahiro; KAWASHIMA, Toshiyuki; KAN, Hirofumi; KURITA, Takashi; NAKAMURA, Naoki; KONDO, Takuya; FUJINE, Manabu; AZUMA, Hirozumi; HIOKI, Tatsumi; KAKENO, Mitsutaka; MOTOHIRO, Tomoyoshi

    2016-01-01

    Pellet injection and repetitive laser illumination are key technologies for realizing inertial fusion energy [1-4]. Neutron generator using lasers also requires a repeating pellet target supplier. Here we present the first demonstration of target injection and neutron generation[5]. We injected more than 1300 spherical deuterated polystyrene(C 8 D 8 ) bead pellet targets during 23 minutes at 1 Hz(Fig. 1). After the pellet targets fell for a distance of 18 cm, we applied the synchronized laser-diode-pumped ultra-intense laser HAMA. The laser intensity at the focal point is 5 x 10 18 W/cm 2 , which is high enough to generate neutrons. As a result of the irradiation, we produced 2.45-MeV DD neutrons. Figure 2 shows the neutron time-of-flight signals detected by plastic scintillators coupled to photomultipliers. The neutron energy was calculated by the time-of-flight method. The maximum neutron yield was 9.5 x 10 4 /4π sr. The result is a step toward fusion power and also suggests possible industrial neutron sources. (paper)

  10. Prediction of pavement remaining service life based on repetition of load and permanent deformation

    Science.gov (United States)

    Usman, R. S.; Setyawan, A.; Suprapto, M.

    2018-03-01

    One of the methods which was applied in the assessment of flexible pavement performance was mechanistic method assuming structures of road pavement to become multi-layer structure for flexible pavement, that the vehicle load working on the pavement layer under repetition with power failure worth 1 (one) unit which was assumed as evenly distributed static load, and therefore the pavement material would provide response in the form of stress, strain, and deflection. This is closely related in order to assess the structure of flexible pavement and to predict the remaining service life on the roads of Pulau Indah sta 0 + 000 to sta. 0 + 845 in Kota Kupang, Nusa Tenggara Timur. The performance appraisal indicator which was used was fatigue cracking happening bottom of the asphalt layer and permanent deformation (rutting) on the surface of subgrade. The strain estimate on the flexible pavement layer structure needs carefulness and high accuracy and therefore a software like KENPAVE which produces horizontal tensile strain of 8,802E-05 and vertical compressive strain of 2,642E-04 was used. By applying equation of The Asphalt Instituteit was obtained repetition of permit load when reaching fatigue cracking (Nf) was 16.071.516 ESAL and permanent deformation (rutting) was 14.703.867 ESAL and also it was predicted the remaining service life of pavement applied the equation of AASTHO 1993 by considering Traffic Multiplier factor (TM 1.8, TM 1.9 and TM 2.0) obtained the remaining life service due to fatigue of 5.51% in the year of 13th (TM 1.8), 7.95% in the year of12th (TM 1.9) and 3.11% (TM 2.0) in the year of 12th, also the remaining service life due to rutting of 4.69% in the year of 12th(TM 1.8), 7.79% in the year of 11th (TM 1.9), and 2.94 in the year of 11th (TM 2.0).

  11. Contribution of fronto-striatal regions to emotional valence and repetition under cognitive conflict.

    Science.gov (United States)

    Chun, Ji-Won; Park, Hae-Jeong; Kim, Dai Jin; Kim, Eosu; Kim, Jae-Jin

    2017-07-01

    Conflict processing mediated by fronto-striatal regions may be influenced by emotional properties of stimuli. This study aimed to examine the effects of emotion repetition on cognitive control in a conflict-provoking situation. Twenty-one healthy subjects were scanned using functional magnetic resonance imaging while performing a sequential cognitive conflict task composed of emotional stimuli. The regional effects were analyzed according to the repetition or non-repetition of cognitive congruency and emotional valence between the preceding and current trials. Post-incongruence interference in error rate and reaction time was significantly smaller than post-congruence interference, particularly under repeated positive and non-repeated positive, respectively, and post-incongruence interference, compared to post-congruence interference, increased activity in the ACC, DLPFC, and striatum. ACC and DLPFC activities were significantly correlated with error rate or reaction time in some conditions, and fronto-striatal connections were related to the conflict processing heightened by negative emotion. These findings suggest that the repetition of emotional stimuli adaptively regulates cognitive control and the fronto-striatal circuit may engage in the conflict adaptation process induced by emotion repetition. Both repetition enhancement and repetition suppression of prefrontal activity may underlie the relationship between emotion and conflict adaptation. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. A longitudinal investigation of perfectionism and repetitive negative thinking in perinatal depression.

    Science.gov (United States)

    Egan, Sarah J; Kane, Robert T; Winton, Karen; Eliot, Catherine; McEvoy, Peter M

    2017-10-01

    Repetitive negative thinking and perfectionism have both been proposed as processes that are related to depressive symptoms. The purpose of this study was to investigate concurrent and prospective relationships between antenatal and postnatal depression, perfectionism, and repetitive negative thinking. A longitudinal design was used and 71 women were followed from their third trimester of pregnancy to six weeks post birth. A structural equation model was tested with antenatal perfectionism predicting antenatal repetitive negative thinking, perfectionism predicting postnatal depression, and antenatal repetitive negative thinking predicting antenatal and postnatal depression. The final model provided an adequate fit to the data but the pathway from antenatal repetitive negative thinking to postnatal depression was not significant. The findings provide support for the role of perfectionism and repetitive negative thinking in the onset and maintenance of perinatal symptoms of depression. It is suggested that future research investigates the efficacy of targeting repetitive negative thinking and perfectionism in pregnancy to examine if this can reduce perinatal depression. Copyright © 2017. Published by Elsevier Ltd.

  13. Word Recognition during Reading: The Interaction between Lexical Repetition and Frequency

    Science.gov (United States)

    Lowder, Matthew W.; Choi, Wonil; Gordon, Peter C.

    2013-01-01

    Memory studies utilizing long-term repetition priming have generally demonstrated that priming is greater for low-frequency words than for high-frequency words and that this effect persists if words intervene between the prime and the target. In contrast, word-recognition studies utilizing masked short-term repetition priming typically show that the magnitude of repetition priming does not differ as a function of word frequency and does not persist across intervening words. We conducted an eye-tracking while reading experiment to determine which of these patterns more closely resembles the relationship between frequency and repetition during the natural reading of a text. Frequency was manipulated using proper names that were high-frequency (e.g., Stephen) or low-frequency (e.g., Dominic). The critical name was later repeated in the sentence, or a new name was introduced. First-pass reading times and skipping rates on the critical name revealed robust repetition-by-frequency interactions such that the magnitude of the repetition-priming effect was greater for low-frequency names than for high-frequency names. In contrast, measures of later processing showed effects of repetition that did not depend on lexical frequency. These results are interpreted within a framework that conceptualizes eye-movement control as being influenced in different ways by lexical- and discourse-level factors. PMID:23283808

  14. BOLD repetition decreases in object-responsive ventral visual areas depend on spatial attention.

    Science.gov (United States)

    Eger, E; Henson, R N A; Driver, J; Dolan, R J

    2004-08-01

    Functional imaging studies of priming-related repetition phenomena have become widely used to study neural object representation. Although blood oxygenation level-dependent (BOLD) repetition decreases can sometimes be observed without awareness of repetition, any role for spatial attention in BOLD repetition effects remains largely unknown. We used fMRI in 13 healthy subjects to test whether BOLD repetition decreases for repeated objects in ventral visual cortices depend on allocation of spatial attention to the prime. Subjects performed a size-judgment task on a probe object that had been attended or ignored in a preceding prime display of 2 lateralized objects. Reaction times showed faster responses when the probe was the same object as the attended prime, independent of the view tested (identical vs. mirror image). No behavioral effect was evident from unattended primes. BOLD repetition decreases for attended primes were found in lateral occipital and fusiform regions bilaterally, which generalized across identical and mirror-image repeats. No repetition decreases were observed for ignored primes. Our results suggest a critical role for attention in achieving visual representations of objects that lead to both BOLD signal decreases and behavioral priming on repeated presentation.

  15. Brain signal complexity rises with repetition suppression in visual learning.

    Science.gov (United States)

    Lafontaine, Marc Philippe; Lacourse, Karine; Lina, Jean-Marc; McIntosh, Anthony R; Gosselin, Frédéric; Théoret, Hugo; Lippé, Sarah

    2016-06-21

    Neuronal activity associated with visual processing of an unfamiliar face gradually diminishes when it is viewed repeatedly. This process, known as repetition suppression (RS), is involved in the acquisition of familiarity. Current models suggest that RS results from interactions between visual information processing areas located in the occipito-temporal cortex and higher order areas, such as the dorsolateral prefrontal cortex (DLPFC). Brain signal complexity, which reflects information dynamics of cortical networks, has been shown to increase as unfamiliar faces become familiar. However, the complementarity of RS and increases in brain signal complexity have yet to be demonstrated within the same measurements. We hypothesized that RS and brain signal complexity increase occur simultaneously during learning of unfamiliar faces. Further, we expected alteration of DLPFC function by transcranial direct current stimulation (tDCS) to modulate RS and brain signal complexity over the occipito-temporal cortex. Participants underwent three tDCS conditions in random order: right anodal/left cathodal, right cathodal/left anodal and sham. Following tDCS, participants learned unfamiliar faces, while an electroencephalogram (EEG) was recorded. Results revealed RS over occipito-temporal electrode sites during learning, reflected by a decrease in signal energy, a measure of amplitude. Simultaneously, as signal energy decreased, brain signal complexity, as estimated with multiscale entropy (MSE), increased. In addition, prefrontal tDCS modulated brain signal complexity over the right occipito-temporal cortex during the first presentation of faces. These results suggest that although RS may reflect a brain mechanism essential to learning, complementary processes reflected by increases in brain signal complexity, may be instrumental in the acquisition of novel visual information. Such processes likely involve long-range coordinated activity between prefrontal and lower order visual

  16. A Review of Repetitive Transcranial Magnetic Stimulation Use in Psychiatry

    Directory of Open Access Journals (Sweden)

    Onur Durmaz

    2013-08-01

    Full Text Available Repetitive transcranial magnetic stimulation (rTMS is a non-invasive brain stimulation technique first introduced by Barker et al. in 1985. The principle of rTMS is based on a cortical neuronal transmembrane potential stimulated by a pulsative magnetic field. This magnetic field is induced by a direct electrical current sent through a circular coil. rTMS is an effective and widely used therapeutic stimulation method for psychiatric disorders, primarily for unipolar depression. Cost-effectiveness, minor side effects and well-tolerated profile of rTMS with no need to hospitalization for administation are the prominent features of this method. Beside the information for depression, rTMS has been reported to have some remarkable impacts in alleviating symptoms of anxiety disorders. Although data regarding efficacy of rTMS in anxiety disorders is conflicting, there are positive outcomes about generalized anxiety disorder, post-traumatic stress disorder and panic disorder whereas results of rTMS treatment in obsessive-compulsive disorder are generally not favorable. Since low frequency stimulation techniques have been found to be effective in treatment of auditory hallucinations, methodological similarity in concerned studies could be accepted as a supportive aspect of efficacy. Additionally, high frequency stimulation techniques applied to prefrontal area have a potential to impact negative symptoms of schizophrenia. With improving novel techniques of this stimulation method, rTMS is being used increasingly in psychiatric disorders. However, some issues concerning rTMS treatment such as maintenance or prophilactic therapy procedures, duration of effect are remain unclear. Hence, we conclude that multicenter sham controlled studies including similar designs, sociodemographic and clinical variables, methodological protocols with larger sample sizes and studies guieded by imaging methods are warranted to determinate efficacy and side effects of rTMS use

  17. Assessment of Vascular Stent Heating with Repetitive Transcranial Magnetic Stimulation.

    Science.gov (United States)

    Varnerin, Nicole; Mirando, David; Potter-Baker, Kelsey A; Cardenas, Jesus; Cunningham, David A; Sankarasubramanian, Vishwanath; Beall, Erik; Plow, Ela B

    2017-05-01

    A high proportion of patients with stroke do not qualify for repetitive transcranial magnetic stimulation (rTMS) clinical studies due to the presence of metallic stents. The ultimate concern is that any metal could become heated due to eddy currents. However, to date, no clinical safety data are available regarding the risk of metallic stents heating with rTMS. We tested the safety of common rTMS protocols (1 Hz and 10 Hz) with stents used commonly in stroke, nitinol and elgiloy. In our method, stents were tested in gelled saline at 2 different locations: at the center and at the lobe of the coil. In addition, at each location, stent heating was evaluated in 3 different orientations: parallel to the long axis of coil, parallel to the short axis of the coil, and perpendicular to the plane of the coil. We found that stents did not heat to more than 1°C with either 1 Hz rTMS or 10 Hz rTMS in any configuration or orientation. Heating in general was greater at the lobe when the stent was oriented perpendicularly. Our study represents a new method for ex vivo quantification of stent heating. We have found that heating of stents was well below the Food and Drug Administration standards of 2°C. Thus, our study paves the way for in vivo testing of rTMS (≤10 Hz) in the presence of implanted magnetic resonance imaging-compatible stents in animal studies. When planning human safety studies though, geometry, orientation, and location relative to the coil would be important to consider as well. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  18. Knowledge of Repetitions Range Affects Force Production in Trained Females

    Directory of Open Access Journals (Sweden)

    Israel Halperin, Saied J. Aboodarda, Fabien A. Basset, David G. Behm

    2014-12-01

    Full Text Available Most studies have examined pacing strategies with cyclical activities (running and cycling. It has been demonstrated that males employ different pacing strategies during repeated maximal voluntary contractions (MVCs dependent upon a known endpoint. Since different fatiguing mechanisms have been identified between the genders, it is not known if females use comparable pacing strategies. The purpose of this study was to examine if informing female subjects regarding the number of MVCs to perform would affect force and electromyography (EMG. Twenty well-trained females completed 3 fatiguing protocols in a randomized order. In the control condition participants were informed they would perform twelve MVCs and then actually completed twelve. In the unknown condition they were not told how many MVCs to perform but were stopped after twelve. In the deception condition they were initially informed to perform 6 MVCs, but after the 6th MVC they were asked to perform a few more MVCs and were stopped after twelve. During the first 6 MVCs, forces in the deception condition were greater compared to the unknown (p = 0.021, ES = 0.65, 5% and control (p = 0.022, ES = 0.42, 3% conditions. No differences were found between conditions in the last 6 MVCs. A main effect for repetitions showed force deficits during the first 6 MVCs (p = 0.000, ES = 1.81, 13% and last 6 MVCs (p = 0.05, ES = 0.34, 3%. No differences were found between conditions in biceps and triceps EMG. However, EMG decreased during the first 6 MVCs for biceps (p = 0.001, ES = 1.0, 14% and triceps (p = 0.001, ES = 0.76, 14% across conditions. No differences were found in the last 6 MVCs. The anticipation of performing fewer MVCs led to increased force, whereas no endpoint led to decreased force production.

  19. Massively parallel fabrication of repetitive nanostructures: nanolithography for nanoarrays

    International Nuclear Information System (INIS)

    Luttge, Regina

    2009-01-01

    This topical review provides an overview of nanolithographic techniques for nanoarrays. Using patterning techniques such as lithography, normally we aim for a higher order architecture similarly to functional systems in nature. Inspired by the wealth of complexity in nature, these architectures are translated into technical devices, for example, found in integrated circuitry or other systems in which structural elements work as discrete building blocks in microdevices. Ordered artificial nanostructures (arrays of pillars, holes and wires) have shown particular properties and bring about the opportunity to modify and tune the device operation. Moreover, these nanostructures deliver new applications, for example, the nanoscale control of spin direction within a nanomagnet. Subsequently, we can look for applications where this unique property of the smallest manufactured element is repetitively used such as, for example with respect to spin, in nanopatterned magnetic media for data storage. These nanostructures are generally called nanoarrays. Most of these applications require massively parallel produced nanopatterns which can be directly realized by laser interference (areas up to 4 cm 2 are easily achieved with a Lloyd's mirror set-up). In this topical review we will further highlight the application of laser interference as a tool for nanofabrication, its limitations and ultimate advantages towards a variety of devices including nanostructuring for photonic crystal devices, high resolution patterned media and surface modifications of medical implants. The unique properties of nanostructured surfaces have also found applications in biomedical nanoarrays used either for diagnostic or functional assays including catalytic reactions on chip. Bio-inspired templated nanoarrays will be presented in perspective to other massively parallel nanolithography techniques currently discussed in the scientific literature. (topical review)

  20. Exploration of verbal repetition in people with dementia using an online symptom-tracking tool.

    Science.gov (United States)

    Reeve, Emily; Molin, Pierre; Hui, Amaris; Rockwood, Kenneth

    2017-06-01

    Online tools can be used by people with dementia and their caregivers to self-identify and track troubling symptoms, such as verbal repetition. We aimed to explore verbal repetition behaviors in people with dementia. Participants were recruited via an online resource for people with dementia and their caregivers. Respondents were instructed to complete information about symptoms that are most important to them for tracking over time. In this cross-sectional study, we analyzed data pertaining to individuals with dementia who had at least three symptoms selected for tracking. Of the 3,573 participants who began a user profile, 1,707 fulfilled criteria for analysis. Verbal repetition was identified as a treatment target in 807 respondents (47.3%). Verbal repetition was more frequent in individuals with mild dementia compared to those with moderate and severe dementia (57.2% vs. 36.0% and 39.9%, p < 0.01) and in those with Alzheimer's disease versus other dementias (65.2% vs. 29.7%, p < 0.001). Repetitive questioning was the most frequent type of verbal repetition (90.5% of individuals with verbal repetition). Verbal repetition was most strongly associated with difficulties operating gadgets/appliances (OR 3.65, 95%CI: 2.82-4.72), lack of interest and/or initiative (3.52: 2.84-4.36), misplacing or losing objects (3.25: 2.64-4.01), and lack of attention and/or concentration (2.62: 2.12-3.26). Verbal repetition is a common symptom in people at all stages of dementia but is most commonly targeted for monitoring and treatment effects in its mild stage. Much research is required to further elucidate the underlying mechanisms and the effect of different treatment strategies.

  1. Genetic diversity of the Mycobacterium tuberculosis Beijing family based on SNP and VNTR typing profiles in Asian countries.

    Directory of Open Access Journals (Sweden)

    Yih-Yuan Chen

    Full Text Available The Mycobacterium tuberculosis (MTB Beijing strain is highly virulent, drug resistant, and endemic over Asia. To explore the genetic diversity of this family in several different regions of eastern Asia, 338 Beijing strains collected in Taiwan (Republic of China were analyzed by mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR typing and compared with published MIRU-VNTR profiles and by the Hunter-Gaston diversity index (HGDI of Beijing strains from Japan and South Korea. The results revealed that VNTR2163b (HGDI>0.6 and five other loci (VNTR424, VNTR4052, VNTR1955, VNTR4156 and VNTR 2996; HGDI>0.3 could be used to discriminate the Beijing strains in a given geographic region. Analysis based on the number of VNTR repeats showed three VNTRs (VNTR424, 3192, and 1955 to be phylogenetically informative loci. In addition, to determine the geographic variation of sequence types in MTB populations, we also compared sequence type (ST data of our strains with published ST profiles of Beijing strains from Japan and Thailand. ST10, ST22, and ST19 were found to be prevalent in Taiwan (82% and Thailand (92%. Furthermore, classification of Beijing sublineages as ancient or modern in Taiwan was found to depend on the repeat number of VNTR424. Finally, phylogenetic relationships of MTB isolates in Taiwan, South Korea, and Japan were revealed by a minimum spanning tree based on MIRU-VNTR genotyping. In this topology, the MIRU-VNTR genotypes of the respective clusters were tightly correlated to other genotypic characters. These results are consistent with the hypothesis that clonal evolution of these MTB lineages has occurred.

  2. Extent of Mycobacterium bovis transmission among animals of dairy and beef cattle and deer farms in South Korea determined by variable-number tandem repeats typing.

    Science.gov (United States)

    Je, Sungmo; Ku, Bok Kyung; Jeon, Bo-Young; Kim, Jae-Myoung; Jung, Suk-Chan; Cho, Sang-Nae

    2015-04-17

    Identifying sources of Mycobacterium bovis transmission would be essential for establishing effective control programs of bovine tuberculosis (TB), a major zoonosis threatening human health worldwide. As an effort to determine the extent of M. bovis transmission among dairy and beef cattle and deer populations, a mycobacterial interspersed repetitive units (MIRU)-variable-number tandem repeats (VNTR) typing method was employed for analysis of 131 M. bovis isolates from 59 Holstein dairy cattle, 39 Korean beef cattle, and 33 deer. Of 31 MIRU-VNTR markers, 15 showed allelic diversity. The most discriminatory locus for M. bovis isolates was VNTR 3336 (h=0.59) followed by QUB 26, MIRU 31, VNTR 2401, and VNTR 3171 which showed high discriminatory power (h=0.43). The combined VNTR loci had an allelic diversity of 0.83. On the basis of the VNTR profiles of 30 VNTR loci, 24 genotypes were identified, and two genotypes were highly prevalent among all M. bovis isolates (33.6% and 19.1%, respectively), thus indicating that more than 50% of the isolates shared common molecular characteristics. Six additional genotypes were common in 2 of the 3 animal species, suggesting a wide interspecies transmission of M. bovis. This study thus demonstrates that MIRU-VNTR typing is useful in differentiation of M. bovis isolates and that M. bovis transmission occurs frequently among farmed animal species, highlighting the importance of bovine TB control programs in different animal species which are often raised in the same villages. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Genetic Diversity of the Mycobacterium tuberculosis Beijing Family Based on SNP and VNTR Typing Profiles in Asian Countries

    Science.gov (United States)

    Chen, Yih-Yuan; Chang, Jia-Ru; Huang, Wei-Feng; Kuo, Shu-Chen; Su, Ih-Jen; Sun, Jun-Ren; Chiueh, Tzong-Shi; Huang, Tsi-Shu; Chen, Yao-Shen; Dou, Horng-Yunn

    2012-01-01

    The Mycobacterium tuberculosis (MTB) Beijing strain is highly virulent, drug resistant, and endemic over Asia. To explore the genetic diversity of this family in several different regions of eastern Asia, 338 Beijing strains collected in Taiwan (Republic of China) were analyzed by mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing and compared with published MIRU-VNTR profiles and by the Hunter-Gaston diversity index (HGDI) of Beijing strains from Japan and South Korea. The results revealed that VNTR2163b (HGDI>0.6) and five other loci (VNTR424, VNTR4052, VNTR1955, VNTR4156 and VNTR 2996; HGDI>0.3) could be used to discriminate the Beijing strains in a given geographic region. Analysis based on the number of VNTR repeats showed three VNTRs (VNTR424, 3192, and 1955) to be phylogenetically informative loci. In addition, to determine the geographic variation of sequence types in MTB populations, we also compared sequence type (ST) data of our strains with published ST profiles of Beijing strains from Japan and Thailand. ST10, ST22, and ST19 were found to be prevalent in Taiwan (82%) and Thailand (92%). Furthermore, classification of Beijing sublineages as ancient or modern in Taiwan was found to depend on the repeat number of VNTR424. Finally, phylogenetic relationships of MTB isolates in Taiwan, South Korea, and Japan were revealed by a minimum spanning tree based on MIRU-VNTR genotyping. In this topology, the MIRU-VNTR genotypes of the respective clusters were tightly correlated to other genotypic characters. These results are consistent with the hypothesis that clonal evolution of these MTB lineages has occurred. PMID:22808061

  4. Product placement in video games: The effect of brand familiarity and repetition on consumers´ memory

    OpenAIRE

    Martí Parreño, José; Bermejo Berros, Jesús; Aldás Manzano, Joaquín

    2017-01-01

    Product placement in video games is gaining momentum as a means to target audiences in an indirect and engaging way. This research uses a 2 (high repetition vs low repetition) x 2 (high brand familiarity vs low brand familiarity) factorial design to test the effects of repetition and brand familiarity on consumers’ memory for brands placed in video games. Results suggest that consumers recall better familiar than unfamiliar brands placed in the video game and repetition increases recall for f...

  5. Design and implementation of fast charging circuit for repetitive compact torus injector

    International Nuclear Information System (INIS)

    Onchi, T.; McColl, D.; Dreval, M.; Wolfe, S.; Xiao, C.; Hirose, A.

    2014-01-01

    A novel circuit for compact torus (CT) injector operated at high repetition rates has been developed. The core technology adopted in the present work is to charge a large storage capacitor bank and quickly charge the CT capacitor bank through a stack of insulated-gate bipolar transistors (IGBTs). A system consisting of IGBTs and slow banks for the repetitive operation has been developed and installed for each discharge circuit of the University of Saskatchewan Compact Torus Injector (USCTI). A repetition rate up to 1.7 Hz and a burst of 8 CTs have been achieved

  6. The Action Plan Against Repetitive Work - An Industrial Relation Strategy for Improving the Working Environment

    DEFF Research Database (Denmark)

    Hasle, Peter; Møller, Niels

    2001-01-01

    The Danish Action Plan against Repetitive Work is presented and discussed as a possible new strategy for regulating repetitive work as well as other complicated working environment problems. The article is based on an empirical evaluation ot the Action Plan. The asseessment of the Action Plan...... indicates that a measurable reduction of repetitive work has been achieved, while recognizing the the new management strategies focusing on human resources development have also played an important role. These results are used to suggest that - under certain conditions - a combination of state regulation...... and industrial relation agreements can be used to regulate other working environment problems....

  7. Repetitive transcranial magnetic stimulation in cervical dystonia: effect of site and repetition in a randomized pilot trial.

    Directory of Open Access Journals (Sweden)

    Sarah Pirio Richardson

    Full Text Available Dystonia is characterized by abnormal posturing due to sustained muscle contraction, which leads to pain and significant disability. New therapeutic targets are needed in this disorder. The objective of this randomized, sham-controlled, blinded exploratory study is to identify a specific motor system target for non-invasive neuromodulation and to evaluate this target in terms of safety and tolerability in the cervical dystonia (CD population. Eight CD subjects were given 15-minute sessions of low-frequency (0.2 Hz repetitive transcranial magnetic stimulation (rTMS over the primary motor cortex (MC, dorsal premotor cortex (dPM, supplementary motor area (SMA, anterior cingulate cortex (ACC and a sham condition with each session separated by at least two days. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS score was rated in a blinded fashion immediately pre- and post-intervention. Secondary outcomes included physiology and tolerability ratings. The mean change in TWSTRS severity score by site was 0.25 ± 1.7 (ACC, -2.9 ± 3.4 (dPM, -3.0 ± 4.8 (MC, -0.5 ± 1.1 (SHAM, and -1.5 ± 3.2 (SMA with negative numbers indicating improvement in symptom control. TWSTRS scores decreased from Session 1 (15.1 ± 5.1 to Session 5 (11.0 ± 7.6. The treatment was tolerable and safe. Physiology data were acquired on 6 of 8 subjects and showed no change over time. These results suggest rTMS can modulate CD symptoms. Both dPM and MC are areas to be targeted in further rTMS studies. The improvement in TWSTRS scores over time with multiple rTMS sessions deserves further evaluation.

  8. Metal Top Adapter ACV0000807, Manufactured by Delfasco, Inc. for Alliant Techsystems, Inc., for PA116 Containers on a 44" x 40" Wood Pallet, First Article Tests (FATs) IAW MIL-STD-1660, "Design Criteria for Ammunition Unit Loads"

    National Research Council Canada - National Science Library

    Dugan, Jeffery L

    2008-01-01

    ...) test units were tested with a load of 2,495 lbs each. The tests accomplished on the test units were the Stacking, Repetitive Shock, Drop, Incline-Impact, Sling Compatibility, Forklifting, and Disassembly Tests...

  9. Composite Monopack for 120mm Mortar, With Plastic Pallet Adapters on a 42" x 53" Wooden Pallet, MIL-STD-1660 Tests, "Design Criteria for Ammunition Unit Loads", and Extreme Temperature Tests

    National Research Council Canada - National Science Library

    Dugan, Jeffery L

    2005-01-01

    .... The test units were tested in accordance with the procedures set forth in MIL-STD-1660. Stacking, repetitive shock, edgewise-rotational drop, incline-impact, forklifting, and disassembly testing were conducted on the test units...

  10. Sands subjected to repetitive vertical loading under zero lateral strain: accumulation models, terminal densities, and settlement

    KAUST Repository

    Chong, Song Hun; Santamarina, Carlos

    2016-01-01

    ). Repetitive vertical loading tests under zero lateral strain conditions are conducted using three different sands packed at initially low and high densities. Test results show that plastic strain accumulation for all sands and density conditions can

  11. Repetitive negative thinking and suicide: a burgeoning literature with need for further exploration.

    Science.gov (United States)

    Law, Keyne C; Tucker, Raymond P

    2017-08-24

    Extant research has found a significant overlap between various repetitive negative thinking (RNT) patterns, such as rumination and worry, across different affective disorders implicating that the process of repetitive negative thinking is likely trans-diagnostic. Furthermore, RNT patterns at the core of psychiatric disorders associated with suicide (e.g., rumination and worry) have been found to be associated with suicide even after accounting for the disorder. A synthesis of existing literature on repetitive negative thoughts suggest that following negative emotional experiences, RNTs may lead to a sense of entrapment and hopelessness that may contribute to the onset of suicidal ideation and then facilitate the transition from thinking about suicide to making a suicide attempt by increasing an individual's capability for suicide through repetitive exposure to violent thoughts and imagery associated with suicide. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Reduction of the beam pulse repetition rate of the Hamburg Isochronous Cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Krause, H; Langkau, R; Schirm, N [Hamburg Univ. (F.R. Germany). 1. Inst. fuer Experimentalphysik

    1976-04-01

    A system for the reduction of the beam pulse repetition rate of the energy-variable Hamburg Isochronous Cyclotron comprising beam pulse supression in the cyclotron center and in the external beam is described.

  13. The use of digit and sentence repetition in the identification of ...

    African Journals Online (AJOL)

    Kate H

    value to child language researchers and speech-language therapists. .... 1801), short term memory of persons with dyslexia (Roach and Hogben ..... The results of the pilot study were used to determine how long the repetition tasks took to.

  14. Effects of slow repetitive transcranial magnetic stimulation in patients with corticobasal syndrome.

    Science.gov (United States)

    Civardi, Carlo; Pisano, Fabrizio; Delconte, Carmen; Collini, Alessandra; Monaco, Francesco

    2015-06-01

    Corticobasal syndrome is characterized by asymmetric cortical sensorimotor dysfunction and parkinsonism; an altered cortical excitability has been reported. We explored with transcranial magnetic stimulation the motor cortical excitability in corticobasal syndrome, and the effects of slow repetitive transcranial magnetic stimulation. With transcranial magnetic stimulation, we studied two corticobasal syndrome patients. We determined bilaterally from the first dorsal interosseous muscle: relaxed threshold, and contralateral and ipsilateral silent period. We also evaluated the contralateral silent period after active/sham slow repetitive transcranial magnetic stimulation on the most affected side. At T0 the silent period was bilaterally short. On the most affected side, active slow repetitive transcranial magnetic stimulation induced a short lasting prolongation of the contralateral silent period. In corticobasal syndrome, transcranial magnetic stimulation showed a reduction cortical inhibitory phenomenon potentially reversed transiently by slow repetitive transcranial magnetic stimulation.

  15. An evaluation of factors affecting duration of treatment with repetitive transcranial magnetic stimulation for depression

    Directory of Open Access Journals (Sweden)

    Roni Broder Cohen

    2007-12-01

    Full Text Available Objective: To investigate the effects of repetitive transcranialmagnetic stimulation in patients with major depression who weresubmitted to this treatment during the period from 2000 to 2006.Methods: A retrospective study with 204 patients who underwenttreatment with repetitive transcranial magnetic stimulation, collectingdata from those who experienced remission (defined as a HDRS scoreequal to or lower than 7. The patients were followed for up to 6 monthsafter treatment. Mean duration of remission for this cohort of patientswas 70.2 (± 58.4 days. Results: The only variable associated withthe duration of remission in the linear regression model was numberof repetitive transcranial magnetic stimulation sessions. Conclusion:Our findings suggest that the greater the number of sessions, the longerthe duration of repetitive transcranial magnetic stimulation effects.Consequently, future research investigating the effects of repetitivetranscranial magnetic stimulation should explore this variable in orderto maximize the therapeutic effects of this new brain stimulationtechnique.

  16. On the mechanisms governing the repetition rate of mode-locked semiconductor lasers

    DEFF Research Database (Denmark)

    Mulet, Josep; Mørk, Jesper

    2004-01-01

    We investigate the mechanisms influencing the synchronization locking range of mode-locked lasers. We find that changes in repetition rates can be accomodated through a joint interplay of dispersion and pulse shaping effects....

  17. Evaluation of Na+/K+ pump function following repetitive activity in mouse peripheral nerve

    DEFF Research Database (Denmark)

    Moldovan, Mihai; Krarup, Christian

    2006-01-01

    excitability measures simultaneously from the evoked plantar compound muscle action potential (CMAP) and sciatic compound nerve action potential (CNAP). Three minutes after repetitive supramaximal stimulation maximal CMAP and CNAP amplitudes recovered but the threshold was increased approximately 40% for motor...

  18. Sustainment of spherical tokamak by means of repetitive injection of compact torus plasma

    International Nuclear Information System (INIS)

    Shimamura, Shin; Matsura, Ken; Takahashi, Tsutomu; Nogi, Yasuyuki

    2000-01-01

    Sustainment of spherical tokamak (S.T.) has been studied. A compact torus (C.T.) plasma was injected into confinement region by magnetized coaxial gun. For start-up and sustainment of large main spherical tokamak, single pulsed injection of small C.T. is not sufficient in many cases. C.T.plasma injection of high repetition rate is required. For this purpose magnetized coaxial gun was driven with high repetition rate current. The first injected C.T. plasma could start-up S.T. without other help. The repetitive C.T. injection grew and sustained the S.T. plasma. A CCD camera with fast gated image intensifier took a cross sectional view of S.T. during the repetitive C.T. injection. (author)

  19. Widespread Chromatin Accessibility at Repetitive Elements Links Stem Cells with Human Cancer

    Directory of Open Access Journals (Sweden)

    Nicholas C. Gomez

    2016-11-01

    Full Text Available Chromatin regulation is critical for differentiation and disease. However, features linking the chromatin environment of stem cells with disease remain largely unknown. We explored chromatin accessibility in embryonic and multipotent stem cells and unexpectedly identified widespread chromatin accessibility at repetitive elements. Integrating genomic and biochemical approaches, we demonstrate that these sites of increased accessibility are associated with well-positioned nucleosomes marked by distinct histone modifications. Differentiation is accompanied by chromatin remodeling at repetitive elements associated with altered expression of genes in relevant developmental pathways. Remarkably, we found that the chromatin environment of Ewing sarcoma, a mesenchymally derived tumor, is shared with primary mesenchymal stem cells (MSCs. Accessibility at repetitive elements in MSCs offers a permissive environment that is exploited by the critical oncogene responsible for this cancer. Our data demonstrate that stem cells harbor a unique chromatin landscape characterized by accessibility at repetitive elements, a feature associated with differentiation and oncogenesis.

  20. Transduction of Repetitive Mechanical Stimuli by Piezo1 and Piezo2 Ion Channels

    Directory of Open Access Journals (Sweden)

    Amanda H. Lewis

    2017-06-01

    Full Text Available Several cell types experience repetitive mechanical stimuli, including vein endothelial cells during pulsating blood flow, inner ear hair cells upon sound exposure, and skin cells and their innervating dorsal root ganglion (DRG neurons when sweeping across a textured surface or touching a vibrating object. While mechanosensitive Piezo ion channels have been clearly implicated in sensing static touch, their roles in transducing repetitive stimulations are less clear. Here, we perform electrophysiological recordings of heterologously expressed mouse Piezo1 and Piezo2 responding to repetitive mechanical stimulations. We find that both channels function as pronounced frequency filters whose transduction efficiencies vary with stimulus frequency, waveform, and duration. We then use numerical simulations and human disease-related point mutations to demonstrate that channel inactivation is the molecular mechanism underlying frequency filtering and further show that frequency filtering is conserved in rapidly adapting mouse DRG neurons. Our results give insight into the potential contributions of Piezos in transducing repetitive mechanical stimuli.

  1. PCR amplification of repetitive sequences as a possible approach in relative species quantification

    DEFF Research Database (Denmark)

    Ballin, Nicolai Zederkopff; Vogensen, Finn Kvist; Karlsson, Anders H

    2012-01-01

    Abstract Both relative and absolute quantifications are possible in species quantification when single copy genomic DNA is used. However, amplification of single copy genomic DNA does not allow a limit of detection as low as one obtained from amplification of repetitive sequences. Amplification...... of repetitive sequences is therefore frequently used in absolute quantification but problems occur in relative quantification as the number of repetitive sequences is unknown. A promising approach was developed where data from amplification of repetitive sequences were used in relative quantification of species...... to relatively quantify the amount of chicken DNA in a binary mixture of chicken DNA and pig DNA. However, the designed PCR primers lack the specificity required for regulatory species control....

  2. Dissociating mere exposure and repetition priming as a function of word type.

    Science.gov (United States)

    Butler, Laurie T; Berry, Dianne C; Helman, Shaun

    2004-07-01

    The mere exposure effect is defined as enhanced attitude toward a stimulus that has been repeatedly exposed. Repetition priming is defined as facilitated processing of a previously exposed stimulus. We conducted a direct comparison between the two phenomena to test the assumption that the mere exposure effect represents an example of repetition priming. In two experiments, having studied a set of words or nonwords, participants were given a repetition priming task (perceptual identification) or one of two mere exposure (affective liking or preference judgment) tasks. Repetition priming was obtained for both words and nonwords, but only nonwords produced a mere exposure effect. This demonstrates a key boundary for observing the mere exposure effect, one not readily accommodated by a perceptual representation systems (Tulving & Schacter, 1990) account, which assumes that both phenomena should show some sensitivity to nonwords and words.

  3. Additive effects of repetition and predictability during comprehension: evidence from event-related potentials.

    Directory of Open Access Journals (Sweden)

    Wing-Yee Chow

    Full Text Available Previous research has shown that neural responses to words during sentence comprehension are sensitive to both lexical repetition and a word's predictability in context. While previous research has often contrasted the effects of these variables (e.g. by looking at cases in which word repetition violates sentence-level constraints, little is known about how they work in tandem. In the current study we examine how recent exposure to a word and its predictability in context combine to impact lexical semantic processing. We devise a novel paradigm that combines reading comprehension with a recognition memory task, allowing for an orthogonal manipulation of a word's predictability and its repetition status. Using event-related brain potentials (ERPs, we show that word repetition and predictability have qualitatively similar and additive effects on the N400 amplitude. We propose that prior exposure to a word and predictability impact lexical semantic processing in an additive and independent fashion.

  4. A dispersion-balanced Discrete Fourier Transform of repetitive pulse sequences using temporal Talbot effect

    Science.gov (United States)

    Fernández-Pousa, Carlos R.

    2017-11-01

    We propose a processor based on the concatenation of two fractional temporal Talbot dispersive lines with balanced dispersion to perform the DFT of a repetitive electrical sequence, for its use as a controlled source of optical pulse sequences. The electrical sequence is used to impart the amplitude and phase of a coherent train of optical pulses by use of a modulator placed between the two Talbot lines. The proposal has been built on a representation of the action of fractional Talbot effect on repetitive pulse sequences and a comparison with related results and proposals. It is shown that the proposed system is reconfigurable within a few repetition periods, has the same processing rate as the input optical pulse train, and requires the same technical complexity in terms of dispersion and pulse width as the standard, passive pulse-repetition rate multipliers based on fractional Talbot effect.

  5. A copper bromide vapour laser with a high pulse repetition rate

    International Nuclear Information System (INIS)

    Shiyanov, D V; Evtushenko, Gennadii S; Sukhanov, V B; Fedorov, V F

    2002-01-01

    The results of an experimental study of a copper bromide vapour laser with a discharge-channel diameter above 2.5 cm and a high pump-pulse repetition rate are presented. A TGU1-1000/25 high-power tacitron used as a switch made it possible to obtain for the first time a fairly high output radiation power for pump-pulse repetition rates exceeding 200 kHz. At a maximum pump-pulse repetition rate of 250 kHz achieved in a laser tube 2.6 cm in diameter and 76 cm long, the output power was 1.5 W. The output powers of 3 and 10.5 W were reached for pump-pulse repetition rates of 200 and 100 kHz, respectively. These characteristics were obtained without circulating a buffer gas and (or) low-concentration active impurities through the active volume. (active media. lasers)

  6. Multivariate prediction of spontaneous repetitive responses in ventricular myocardium exposed in vitro to simulated ischemic conditions.

    Science.gov (United States)

    Schiariti, M; Puddu, P E; Rouet, R

    1994-06-01

    Guinea-pig ventricular myocardium was partly exposed to normal Tyrode's superfusion and partly to altered conditions (using modified Tyrode's solution) set to simulate acute myocardial ischemia (PO2 80 +/- 10 mmHg; no glucose; pH 7.00 +/- 0.05; K+ 12 mM). Using a double-chamber tissue bath and standard microelectrode technique, the occurrence of spontaneous repetitive responses was investigated during simulated ischemia (occlusion) and after reperfusing the previously ischemic superfused tissue with normal Tyrode's solution (reperfusion). In 62 experiments (42 animals) the effects of: (1) duration of simulated ischemia (1321 +/- 435 s), (2) stimulation rate (1002 +/- 549 ms) and (3) number of successive simulated ischemic periods (occlusions) (1.58 +/- 0.92) on: (1) resting membrane potential, (2) action potential amplitude, (3) duration of 50 and 90% action potentials and (4) maximal upstroke velocity of action potential were studied. All variables were considered as gradients (delta) between normal and ischemic tissue. Both during occlusion and upon reperfusion, spontaneous repetitive responses were coded as single, couplets, salvos (three to nine and > 10) or total spontaneous repetitive responses (coded present when at least one of the above-mentioned types was seen). The incidence of total spontaneous repetitive responses was 31% (19/62) on occlusion and 85% (53/62) upon reperfusion. Cox's models (forced and stepwise) were used to predict multivariately the occurrence of arrhythmic events considered as both total spontaneous repetitive responses and as separate entities. These models were applicable since continuous monitoring of the experiments enabled exact timing of spontaneous repetitive response onset during both occlusion and reperfusion. In predicting reperfusion spontaneous repetitive responses, total spontaneous repetitive responses and blocks observed during the occlusion period were also considered. Total occlusion spontaneous repetitive responses

  7. An effective repetitive training schedule to achieve skill proficiency using a novel robotic virtual reality simulator.

    Science.gov (United States)

    Kang, Sung Gu; Ryu, Byung Ju; Yang, Kyung Sook; Ko, Young Hwii; Cho, Seok; Kang, Seok Ho; Patel, Vipul R; Cheon, Jun

    2015-01-01

    A robotic virtual reality simulator (Mimic dV-Trainer) can be a useful training method for the da Vinci surgical system. Herein, we investigate several repetitive training schedules and determine which is the most effective. A total of 30 medical students were enrolled and were divided into 3 groups according to the training schedule. Group 1 performed the task 1 hour daily for 4 consecutive days, group II performed the task on once per week for 1 hour for 4 consecutive weeks, and group III performed the task for 4 consecutive hours in 1 day. The effects of training were investigated by analyzing the number of repetitions and the time required to complete the "Tube 2" simulation task when the learning curve plateau was reached. The point at which participants reached a stable score was evaluated using the cumulative sum control graph. The average time to complete the task at the learning curve plateau was 150.3 seconds in group I, 171.9 seconds in group II, and 188.5 seconds in group III. The number of task repetitions required to reach the learning curve plateau was 45 repetitions in group I, 36 repetitions in group II, and 39 repetitions in group III. Therefore, there was continuous improvement in the time required to perform the task after 40 repetitions in group I only. There was a significant correlation between improvement in each trial interval and attempt, and the correlation coefficient (0.924) in group I was higher than that in group II (0.899) and group III (0.838). Daily 1-hour practice sessions performed for 4 consecutive days resulted in the best final score, continuous score improvement, and effective training while minimizing fatigue. This repetition schedule can be used for effectively training novices in future. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  8. Outcomes in spasticity after repetitive transcranial magnetic and transcranial direct current stimulations

    OpenAIRE

    Gunduz, Aysegul; Kumru, Hatice; Pascual-Leone, Alvaro

    2014-01-01

    Non-invasive brain stimulations mainly consist of repetitive transcranial magnetic stimulation and transcranial direct current stimulation. Repetitive transcranial magnetic stimulation exhibits satisfactory outcomes in improving multiple sclerosis, stroke, spinal cord injury and cerebral palsy-induced spasticity. By contrast, transcranial direct current stimulation has only been studied in post-stroke spasticity. To better validate the efficacy of non-invasive brain stimulations in improving ...

  9. Repetitive Transcranial Magnetic Stimulation: a Novel Approach for Treating Oropharyngeal Dysphagia

    OpenAIRE

    Michou, Emilia; Raginis-Zborowska, Alicja; Watanabe, Masahiro; Lodhi, Taha; Hamdy, Shaheen

    2016-01-01

    In recent years, repetitive transcranial magnetic stimulation, a technique used to produce human central neurostimulation, has attracted increased interest and been applied experimentally in the treatment of dysphagia. This review presents a synopsis of the current research for the application of repetitive transcranial magnetic stimulation (rTMS) on dysphagia. Here, we review the mechanisms underlying the effects of rTMS and the results from studies on both healthy volunteers and dysphagic p...

  10. Femtosecond Ti:sapphire cryogenic amplifier with high gain and MHz repetition rate

    DEFF Research Database (Denmark)

    Dantan, Aurelien Romain; Laurat, Julien; Ourjoumtsev, Alexei

    2007-01-01

    We demonstrate high gain amplification of 160-femtosecond pulses in a compact double-pass cryogenic Ti:sapphire amplifier. The setup involves a negative GVD mirrors recompression stage, and operates with a repetition rate between 0.2 and 4 MHz with a continuous pump laser. Amplification factors a...... as high as 17 and 320 nJ Fourier-limited pulses are obtained at a 800 kHz repetition rate....

  11. Risk of repetition of suicide attempt, suicide or all deaths after an episode of attempted suicide

    DEFF Research Database (Denmark)

    Christiansen, Erik; Jensen, Børge Frank

    2007-01-01

    This study was undertaken in order to estimate the incidence of repetition of suicide attempt, suicide and all deaths, and to analyse the influence of psychiatric illness and socio-demographic factors on these.......This study was undertaken in order to estimate the incidence of repetition of suicide attempt, suicide and all deaths, and to analyse the influence of psychiatric illness and socio-demographic factors on these....

  12. Concreteness of Positive, Negative, and Neutral Repetitive Thinking About the Future

    Science.gov (United States)

    Behar, Evelyn; McGowan, Sarah Kate; McLaughlin, Katie A.; Borkovec, T.D.; Goldwin, Michelle; Bjorkquist, Olivia

    2014-01-01

    Consistent with assertions that the adaptiveness of repetitive thinking is influenced by both its valence and style, Stöber (e.g., Stöber & Borkovec, 2002) has argued that worry is characterized by a reduced concreteness of thought content and that the resulting abstractness contributes to its inhibition of some aspects of anxious responding. However, extant research does not provide a direct test of Stöber’s reduced concreteness theory of worry. We sought to test Stöber’s theory and to examine the adaptiveness of repetitive worrisome thinking by randomly assigning 108 participants to engage in five consecutive periods of repetitive thinking about positively, negatively, or neutrally valenced potential future events. Results based on coding of thought data indicated that (a) repetitive thinking became increasingly less concrete as periods progressed; (b) contrary to Stöber’s theory, both negative and positive repetitive future thinking were more concrete than neutral repetitive future thinking (and did not differ from each other); and (c) abstractness of thought during negative repetitive future thinking was associated with reduced reports of imagery-based activity. Results based on self-reported affect indicated that negatively valenced repetitive future thinking was uniquely associated with initial decreases in anxious affect, followed by increased anxious affect that coincided with increased imagery-based activity. This suggests that worry is associated with a sequential mitigation of anxious meaning followed by a strengthening of anxious meaning over time. Theoretical and clinical implications of these findings are discussed. PMID:22440067

  13. Methylation patterns of repetitive DNA sequences in germ cells of Mus musculus.

    OpenAIRE

    Sanford, J; Forrester, L; Chapman, V; Chandley, A; Hastie, N

    1984-01-01

    The major and the minor satellite sequences of Mus musculus were undermethylated in both sperm and oocyte DNAs relative to the amount of undermethylation observed in adult somatic tissue DNA. This hypomethylation was specific for satellite sequences in sperm DNA. Dispersed repetitive and low copy sequences show a high degree of methylation in sperm DNA; however, a dispersed repetitive sequence was undermethylated in oocyte DNA. This finding suggests a difference in the amount of total genomic...

  14. Effect of Bench Press Load Knowledge on Repetitions, Rating of Perceived Exertion, and Attentional Focus.

    Science.gov (United States)

    Beaudoin, Christina M; Cox, Zachary; Dundore, Tyler; Thomas, Tayler; Kim, Johnathon; Pillivant, Daniel

    2018-02-01

    Beaudoin, CM, Cox, Z, Dundore, T, Thomas, T, Kim, J, and Pillivant, D. Effect of bench press load knowledge on repetitions, rating of perceived exertion, and attentional focus. J Strength Cond Res 32(2): 514-519, 2018-Few studies have examined the role of the teleoanticipation during resistance training. The purpose of this study was to examine the effect of bench press (BP) load knowledge on repetitions completed, ratings of perceived exertion (RPEs), and attentional focus (% associative). Thirty-six recreationally active resistance-trained men (n = 25) and women (n = 11) participated in this study (age = 20.97 ± 1.87 years; ht = 174.12 ± 9.41 cm; and mass = 80.14 ± 14.03 kg). All subjects completed 3 testing sessions: (a) 1 repetition maximum (1RM) BP determination; (b) submaximal BP repetitions to fatigue known load (KL); and (c) submaximal BP repetitions to fatigue unknown load (UL). Known load and UL sessions were randomized and counterbalanced and both completed at 70% 1RM. An estimated weight ratio was computed using the subject's estimate of the UL weight relative to the KL weight. An independent samples t-test revealed no significant testing order difference for the estimated weight ratio. Two-way repeated-measures analysis of variances revealed no significant differences in the number of repetitions (p = 0.63), RPE (p = 0.18), or attentional focus (% associative) (p = 0.93) between the KL and UL conditions. Pearson correlations found a moderate positive association between KL repetitions completed and % associative focus when the UL was completed before the KL. Load knowledge did not influence the number of repetitions, RPE, or attentional focus while completing the BP. Further research examining the use of pacing strategies, RPE, and attentional focus during KL and UL conditions are warranted.

  15. Measuring Glial Metabolism in Repetitive Brain Trauma and Alzheimer’s Disease

    Science.gov (United States)

    2016-09-01

    stages of repetitive brain trauma as well. Current methods of measure brain glutamate using proton spectroscopy is not specific to different cell...covering a representative range of clinical cases: a young female , young male , middle-aged male (all healthy volunteers) and a male patient with...AWARD NUMBER: W81XWH-15-1-0412 TITLE: Measuring Glial Metabolism in Repetitive Brain Trauma and Alzheimer’s Disease PRINCIPAL INVESTIGATOR

  16. Scaling of black silicon processing time by high repetition rate femtosecond lasers

    Directory of Open Access Journals (Sweden)

    Nava Giorgio

    2013-11-01

    Full Text Available Surface texturing of silicon substrates is performed by femtosecond laser irradiation at high repetition rates. Various fabrication parameters are optimized in order to achieve very high absorptance in the visible region from the micro-structured silicon wafer as compared to the unstructured one. A 70-fold reduction of the processing time is demonstrated by increasing the laser repetition rate from 1 kHz to 200 kHz. Further scaling up to 1 MHz can be foreseen.

  17. Molecular typing of Lactobacillus brevis isolates from Korean food using repetitive element-polymerase chain reaction.

    Science.gov (United States)

    Kaur, Jasmine; Sharma, Anshul; Lee, Sulhee; Park, Young-Seo

    2018-06-01

    Lactobacillus brevis is a part of a large family of lactic acid bacteria that are present in cheese, sauerkraut, sourdough, silage, cow manure, feces, and the intestinal tract of humans and rats. It finds its use in food fermentation, and so is considered a "generally regarded as safe" organism. L. brevis strains are extensively used as probiotics and hence, there is a need for identifying and characterizing these strains. For identification and discrimination of the bacterial species at the subspecific level, repetitive element-polymerase chain reaction method is a reliable genomic fingerprinting tool. The objective of the present study was to characterize 13 strains of L. brevis isolated from various fermented foods using repetitive element-polymerase chain reaction. Repetitive element-polymerase chain reaction was performed using three primer sets, REP, Enterobacterial Repetitive Intergenic Consensus (ERIC), and (GTG) 5 , which produced different fingerprinting patterns that enable us to distinguish between the closely related strains. Fingerprinting patterns generated band range in between 150 and 5000 bp with REP, 200-7500 bp with ERIC, and 250-2000 bp with (GTG) 5 primers, respectively. The Jaccard's dissimilarity matrices were used to obtain dendrograms by the unweighted neighbor-joining method using genetic dissimilarities based on repetitive element-polymerase chain reaction fingerprinting data. Repetitive element-polymerase chain reaction proved to be a rapid and easy method that can produce reliable results in L. brevis species.

  18. Repetition and brain potentials when recognizing natural scenes: task and emotion differences

    Science.gov (United States)

    Bradley, Margaret M.; Codispoti, Maurizio; Karlsson, Marie; Lang, Peter J.

    2013-01-01

    Repetition has long been known to facilitate memory performance, but its effects on event-related potentials (ERPs), measured as an index of recognition memory, are less well characterized. In Experiment 1, effects of both massed and distributed repetition on old–new ERPs were assessed during an immediate recognition test that followed incidental encoding of natural scenes that also varied in emotionality. Distributed repetition at encoding enhanced both memory performance and the amplitude of an old–new ERP difference over centro-parietal sensors. To assess whether these repetition effects reflect encoding or retrieval differences, the recognition task was replaced with passive viewing of old and new pictures in Experiment 2. In the absence of an explicit recognition task, ERPs were completely unaffected by repetition at encoding, and only emotional pictures prompted a modestly enhanced old–new difference. Taken together, the data suggest that repetition facilitates retrieval processes and that, in the absence of an explicit recognition task, differences in old–new ERPs are only apparent for affective cues. PMID:22842817

  19. A feasible repetitive transcranial magnetic stimulation clinical protocol in migraine prevention.

    Science.gov (United States)

    Zardouz, Shawn; Shi, Lei; Leung, Albert

    2016-01-01

    This case series was conducted to determine the clinical feasibility of a repetitive transcranial magnetic stimulation protocol for the prevention of migraine (with and without aura). Five patients with migraines underwent five repetitive transcranial magnetic stimulation sessions separated in 1- to 2-week intervals for a period of 2 months at a single tertiary medical center. Repetitive transcranial magnetic stimulation was applied to the left motor cortex with 2000 pulses (20 trains with 1s inter-train interval) delivered per session, at a frequency of 10 Hz and 80% resting motor threshold. Pre- and post-treatment numerical rating pain scales were collected, and percent reductions in intensity, frequency, and duration were generated. An average decrease in 37.8%, 32.1%, and 31.2% were noted in the intensity, frequency, and duration of migraines post-repetitive transcranial magnetic stimulation, respectively. A mean decrease in 1.9±1.0 (numerical rating pain scale ± standard deviation; range: 0.4-2.8) in headache intensity scores was noted after the repetitive transcranial magnetic stimulation sessions. The tested repetitive transcranial magnetic stimulation protocol is a well-tolerated, safe, and effective method for migraine prevention.

  20. Repetitive laser fusion experiment and operation using a target injection system

    International Nuclear Information System (INIS)

    Nishimura, Yasuhiko; Komeda, Osamu; Mori, Yoshitaka

    2017-01-01

    Since 2008, a collaborative research project on laser fusion development based on a high-speed ignition method using repetitive laser has been carried out with several collaborative research institutes. This paper reports the current state of operation of high repetition laser fusion experiments, such as target introduction and control based on a target injection system that allows free falling under 1 Hz, using a high repetition laser driver that has been under research and development, as well as the measurement of targets that freely fall. The HAMA laser driver that enabled high repetition fusion experiments is a titanium sapphire laser using a diode-pumped solid-state laser KURE-I of green light output as a driver pump light source. In order to carry out high repetition laser fusion experiments, the target injection device allows free falling of deuterated polystyrene solid sphere targets of 1 mm in diameter under 1 Hz. The authors integrated the developed laser and injection system, and succeeded first in the world in making the nuclear fusion reaction continuously by hitting the target to be injected with laser, which is essential technology for future laser nuclear fusion reactor. In order to realize repetition laser fusion experiments, stable laser, target synchronization control, and target position measurement technologies are indispensable. (A.O.)

  1. Independent and additive repetition priming of motion direction and color in visual search.

    Science.gov (United States)

    Kristjánsson, Arni

    2009-03-01

    Priming of visual search for Gabor patch stimuli, varying in color and local drift direction, was investigated. The task relevance of each feature varied between the different experimental conditions compared. When the target defining dimension was color, a large effect of color repetition was seen as well as a smaller effect of the repetition of motion direction. The opposite priming pattern was seen when motion direction defined the target--the effect of motion direction repetition was this time larger than for color repetition. Finally, when neither was task relevant, and the target defining dimension was the spatial frequency of the Gabor patch, priming was seen for repetition of both color and motion direction, but the effects were smaller than in the previous two conditions. These results show that features do not necessarily have to be task relevant for priming to occur. There is little interaction between priming following repetition of color and motion, these two features show independent and additive priming effects, most likely reflecting that the two features are processed at separate processing sites in the nervous system, consistent with previous findings from neuropsychology & neurophysiology. The implications of the findings for theoretical accounts of priming in visual search are discussed.

  2. Longer repetition duration increases muscle activation and blood lactate response in matched resistance training protocols

    Directory of Open Access Journals (Sweden)

    Hugo Cesar Martins-Costa

    2016-03-01

    Full Text Available Abstract This study analyzed the effect of different repetition durations on electromyographic and blood lactate responses of the bench press exercise. Fifteen recreationally trained male volunteers completed two training protocols, matched for intensity (% one-repetition maximum; 1RM, number of sets, number of repetitions, and rest intervals. One of the protocols was performed with a repetition duration of 4 s (2 s concentric: 2 s eccentric; 2:2 protocol, whereas the second protocol had a repetition duration of 6 s (2 s concentric: 4 s eccentric; 2:4 protocol. The results showed higher normalized integrated electromyography (pectoralis major and triceps brachii for the 2:4 protocol. Blood lactate concentration was also higher in the 2:4 protocol across all sets. These results show that adding 2 s to the eccentric action in matched training protocols increases muscle activation and blood lactate response, which reinforces the notion that increasing repetition duration is an alternative load progression in resistance training.

  3. Shoulder muscle fatigue during repetitive tasks as measured by electromyography and near-infrared spectroscopy.

    Science.gov (United States)

    Ferguson, Sue A; Allread, W Gary; Le, Peter; Rose, Joseph; Marras, William S

    2013-12-01

    The objective of this study was to quantify shoulder muscle fatigue during repetitive exertions similar to motions found in automobile assembly tasks. Shoulder musculoskeletal disorders (MSDs) are a common and costly problem in automotive manufacturing. Ten subjects participated in the study. There were three independent variables: shoulder angle, frequency, and force. There were two types of dependent measures: percentage change in near-infrared spectroscopy (NIRS) measures and change in electromyography (EMG) median frequency. The anterior deltoid and trapezius muscles were measured for both NIRS and EMG. Also, EMG was collected on the middle deltoid and biceps muscles. The results showed that oxygenated hemoglobin decreased significantly due to the main effects (shoulder angle, frequency, and force). The percentage change in oxygenated hemoglobin had a significant interaction attributable to force and repetition for the anterior deltoid muscle, indicating that as repetition increased, the magnitude of the differences between the forces increased. The interaction of repetition and shoulder angle was also significant for the percentage change in oxygenated hemoglobin. The median frequency decreased significantly for the main effects; however, no interactions were statistically significant. There was significant shoulder muscle fatigue as a function of shoulder angle, task frequency, and force level. Furthermore, percentage change in oxygenated hemoglobin had two statistically significant interactions, enhancing our understanding of these risk factors. Ergonomists should examine interactions of force and repetition as well as shoulder angle and repetition when evaluating the risk of shoulder MSDs.

  4. Nonword Repetition and Vocabulary Knowledge as Predictors of Children's Phonological and Semantic Word Learning.

    Science.gov (United States)

    Adlof, Suzanne M; Patten, Hannah

    2017-03-01

    This study examined the unique and shared variance that nonword repetition and vocabulary knowledge contribute to children's ability to learn new words. Multiple measures of word learning were used to assess recall and recognition of phonological and semantic information. Fifty children, with a mean age of 8 years (range 5-12 years), completed experimental assessments of word learning and norm-referenced assessments of receptive and expressive vocabulary knowledge and nonword repetition skills. Hierarchical multiple regression analyses examined the variance in word learning that was explained by vocabulary knowledge and nonword repetition after controlling for chronological age. Together with chronological age, nonword repetition and vocabulary knowledge explained up to 44% of the variance in children's word learning. Nonword repetition was the stronger predictor of phonological recall, phonological recognition, and semantic recognition, whereas vocabulary knowledge was the stronger predictor of verbal semantic recall. These findings extend the results of past studies indicating that both nonword repetition skill and existing vocabulary knowledge are important for new word learning, but the relative influence of each predictor depends on the way word learning is measured. Suggestions for further research involving typically developing children and children with language or reading impairments are discussed.

  5. A compact control system to achieve stable voltage and low jitter trigger for repetitive intense electron-beam accelerator based on resonant charging

    Science.gov (United States)

    Qiu, Yongfeng; Liu, Jinliang; Yang, Jianhua; Cheng, Xinbing; Yang, Xiao

    2017-08-01

    A compact control system based on Delphi and Field Programmable Gate Array(FPGA) is developed for a repetitive intense electron-beam accelerator(IEBA), whose output power is 10GW and pulse duration is 160ns. The system uses both hardware and software solutions. It comprises a host computer, a communication module and a main control unit. A device independent applications programming interface, devised using Delphi, is installed on the host computer. Stability theory of voltage in repetitive mode is analyzed and a detailed overview of the hardware and software configuration is presented. High voltage experiment showed that the control system fulfilled the requests of remote operation and data-acquisition. The control system based on a time-sequence control method is used to keep constant of the voltage of the primary capacitor in every shot, which ensured the stable and reliable operation of the electron beam accelerator in the repetitive mode during the experiment. Compared with the former control system based on Labview and PIC micro-controller developed in our laboratory, the present one is more compact, and with higher precision in the time dimension. It is particularly useful for automatic control of IEBA in the high power microwave effects research experiments where pulse-to-pulse reproducibility is required.

  6. Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders A meta-analysis***

    Institute of Scientific and Technical Information of China (English)

    Yingli Zhang; Wei Liang; Shichang Yang; Ping Dai; Lijuan Shen; Changhong Wang

    2013-01-01

    OBJECTIVE: This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hal ucination of patients with schizophrenia spectrum disorders. DATA SOURCES: Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Control ed Trials databases from January 1985 to May 2012. Key words were “transcranial magnetic stimulation”, “TMS”, “repetitive transcranial magnetic stimulation”, and “hal ucination”. STUDY SELECTION: Selected studies were randomized control ed trials assessing therapeutic ef-ficacy of repetitive transcranial magnetic stimulation for hal ucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hal ucination in schizophrenia spectrum disorders. Control groups received sham stimulation. MAIN OUTCOME MEASURES: The primary outcome was total scores of Auditory Hal ucinations Rating Scale, Auditory Hal ucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hal ucination item, and Hal ucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. RESULTS: Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. Al data were completely effective, involving 398 patients. Overal mean weighted effect size for repeti-tive transcranial magnetic stimulation versus sham stimulation was statistical y significant (MD =-0.42, 95%CI: -0.64 to -0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%CI: 1.39 to 6.24, P =0.005). No significant differences were found

  7. Interface unit

    NARCIS (Netherlands)

    Keyson, D.V.; Freudenthal, A.; De Hoogh, M.P.A.; Dekoven, E.A.M.

    2001-01-01

    The invention relates to an interface unit comprising at least a display unit for communication with a user, which is designed for being coupled with a control unit for at least one or more parameters in a living or working environment, such as the temperature setting in a house, which control unit

  8. Facilitation of speech repetition accuracy by theta burst stimulation of the left posterior inferior frontal gyrus.

    Science.gov (United States)

    Restle, Julia; Murakami, Takenobu; Ziemann, Ulf

    2012-07-01

    The posterior part of the inferior frontal gyrus (pIFG) in the left hemisphere is thought to form part of the putative human mirror neuron system and is assigned a key role in mapping sensory perception onto motor action. Accordingly, the pIFG is involved in motor imitation of the observed actions of others but it is not known to what extent speech repetition of auditory-presented sentences is also a function of the pIFG. Here we applied fMRI-guided facilitating intermittent theta burst transcranial magnetic stimulation (iTBS), or depressant continuous TBS (cTBS), or intermediate TBS (imTBS) over the left pIFG of healthy subjects and compared speech repetition accuracy of foreign Japanese sentences before and after TBS. We found that repetition accuracy improved after iTBS and, to a lesser extent, after imTBS, but remained unchanged after cTBS. In a control experiment, iTBS was applied over the left middle occipital gyrus (MOG), a region not involved in sensorimotor processing of auditory-presented speech. Repetition accuracy remained unchanged after iTBS of MOG. We argue that the stimulation type and stimulation site specific facilitating effect of iTBS over left pIFG on speech repetition accuracy indicates a causal role of the human left-hemispheric pIFG in the translation of phonological perception to motor articulatory output for repetition of speech. This effect may prove useful in rehabilitation strategies that combine repetitive speech training with iTBS of the left pIFG in speech disorders, such as aphasia after cerebral stroke. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. The development of a repetition-load scheme for the eccentric-only bench press exercise.

    Science.gov (United States)

    Moir, Gavin L; Erny, Kyle F; Davis, Shala E; Guers, John J; Witmer, Chad A

    2013-01-01

    The purpose of the present study was to develop a repetition-load scheme for the eccentric-only bench press exercise. Nine resistance trained men (age: 21.6 ± 1.0 years; 1-repetition maximum [RM] bench press: 137.7 ± 30.4 kg) attended four testing sessions during a four week period. During the first session each subject's 1-RM bench press load utilizing the stretch-shortening cycle was determined. During the remaining sessions they performed eccentric-only repetitions to failure using supra-maximal loads equivalent to 110%, 120% and 130% of their 1-RM value with a constant cadence (30 reps·min(-1)). Force plates and a three dimensional motion analysis system were used during these final three sessions in order to evaluate kinematic and kinetic variables. More repetitions were completed during the 110% 1-RM condition compared to the 130% 1-RM condition (p=0.01). Mean total work (p=0.046) as well as vertical force (p=0.049), vertical work (p=0.017), and vertical power output (p=0.05) were significantly greater during the 130% 1-RM condition compared to the 110% 1-RM condition. A linear function was fitted to the number of repetitions completed under each load condition that allowed the determination of the maximum number of repetitions that could be completed under other supra-maximal loads. This linear function predicted an eccentric-only 1-RM in the bench press with a load equivalent to 164.8% 1-RM, producing a load of 227.0 ± 50.0 kg. The repetition-load scheme presented here should provide a starting point for researchers to investigate the kinematic, kinetic and metabolic responses to eccentric-only bench press workouts.

  10. Combined effect of repetitive work and cold on muscle function and fatigue.

    Science.gov (United States)

    Oksa, Juha; Ducharme, Michel B; Rintamäki, Hannu

    2002-01-01

    This study compared the effect of repetitive work in thermoneutral and cold conditions on forearm muscle electromyogram (EMG) and fatigue. We hypothesize that cold and repetitive work together cause higher EMG activity and fatigue than repetitive work only, thus creating a higher risk for overuse injuries. Eight men performed six 20-min work bouts at 25 degrees C (W-25) and at 5 degrees C while exposed to systemic (C-5) and local cooling (LC-5). The work was wrist flexion-extension exercise at 10% maximal voluntary contraction. The EMG activity of the forearm flexors and extensors was higher during C-5 (31 and 30%, respectively) and LC-5 (25 and 28%, respectively) than during W-25 (P forearm flexors at the end of W-25 was 15%. The corresponding values at the end of C-5 and LC-5 were 37% (P < 0.05 in relation to W-25) and 20%, respectively. Thus repetitive work in the cold causes higher EMG activity and fatigue than repetitive work in thermoneutral conditions.

  11. Repetitive transient extraction for machinery fault diagnosis using multiscale fractional order entropy infogram

    Science.gov (United States)

    Xu, Xuefang; Qiao, Zijian; Lei, Yaguo

    2018-03-01

    The presence of repetitive transients in vibration signals is a typical symptom of local faults of rotating machinery. Infogram was developed to extract the repetitive transients from vibration signals based on Shannon entropy. Unfortunately, the Shannon entropy is maximized for random processes and unable to quantify the repetitive transients buried in heavy random noise. In addition, the vibration signals always contain multiple intrinsic oscillatory modes due to interaction and coupling effects between machine components. Under this circumstance, high values of Shannon entropy appear in several frequency bands or high value of Shannon entropy doesn't appear in the optimal frequency band, and the infogram becomes difficult to interpret. Thus, it also becomes difficult to select the optimal frequency band for extracting the repetitive transients from the whole frequency bands. To solve these problems, multiscale fractional order entropy (MSFE) infogram is proposed in this paper. With the help of MSFE infogram, the complexity and nonlinear signatures of the vibration signals can be evaluated by quantifying spectral entropy over a range of scales in fractional domain. Moreover, the similarity tolerance of MSFE infogram is helpful for assessing the regularity of signals. A simulation and two experiments concerning a locomotive bearing and a wind turbine gear are used to validate the MSFE infogram. The results demonstrate that the MSFE infogram is more robust to the heavy noise than infogram and the high value is able to only appear in the optimal frequency band for the repetitive transient extraction.

  12. N-2 repetition leads to a cost within working memory and a benefit outside it.

    Science.gov (United States)

    Kessler, Yoav

    2018-03-15

    Removal has been suggested to play a key role in controlling the contents of working memory. The present study examined the aftereffects of removal in a working memory updating task. Participants performed the reference-back paradigm, a version of the n-back task that is composed of two trial types: reference trials that required working memory updating and comparison trials that did not require updating. N-2 repetition effects-the difference in performance between trials that presented the same stimulus as the one presented two trials before (ABA sequences) and trials in which the stimulus differed from the two previous stimuli (ABC sequences)-were examined. In two experiments, n-2 repetition costs were observed within sequences of reference trials, while n-2 repetition benefits were observed within sequences of comparison trials. This pattern suggests that removal takes place during working memory updating. Furthermore, automatic formation and updating of representation outside working memory, which takes place in comparison trials and gives rise to n-2 repetition benefits, does not involve removal. Removal, demonstrated by phenomena such as n-2 repetition costs, is therefore proposed to be a marker for the utilization of working memory within a given task. © 2018 New York Academy of Sciences.

  13. Exact and conceptual repetition dissociate conceptual memory tests: problems for transfer appropriate processing theory.

    Science.gov (United States)

    McDermott, K B; Roediger, H L

    1996-03-01

    Three experiments examined whether a conceptual implicit memory test (specifically, category instance generation) would exhibit repetition effects similar to those found in free recall. The transfer appropriate processing account of dissociations among memory tests led us to predict that the tests would show parallel effects; this prediction was based upon the theory's assumption that conceptual tests will behave similarly as a function of various independent variables. In Experiment 1, conceptual repetition (i.e., following a target word [e.g., puzzles] with an associate [e.g., jigsaw]) did not enhance priming on the instance generation test relative to the condition of simply presenting the target word once, although this manipulation did affect free recall. In Experiment 2, conceptual repetition was achieved by following a picture with its corresponding word (or vice versa). In this case, there was an effect of conceptual repetition on free recall but no reliable effect on category instance generation or category cued recall. In addition, we obtained a picture superiority effect in free recall but not in category instance generation. In the third experiment, when the same study sequence was used as in Experiment 1, but with instructions that encouraged relational processing, priming on the category instance generation task was enhanced by conceptual repetition. Results demonstrate that conceptual memory tests can be dissociated and present problems for Roediger's (1990) transfer appropriate processing account of dissociations between explicit and implicit tests.

  14. Laterality of repetitive finger movement performance and clinical features of Parkinson's disease.

    Science.gov (United States)

    Stegemöller, Elizabeth; Zaman, Andrew; MacKinnon, Colum D; Tillman, Mark D; Hass, Chris J; Okun, Michael S

    2016-10-01

    Impairments in acoustically cued repetitive finger movement often emerge at rates near to and above 2Hz in persons with Parkinson's Disease (PD) in which some patients move faster (hastening) and others move slower (bradykinetic). The clinical features impacting this differential performance of repetitive finger movement remain unknown. The purpose of this study was to compare repetitive finger movement performance between the more and less affected side, and the difference in clinical ratings among performance groups. Forty-one participants diagnosed with idiopathic PD completed an acoustically cued repetitive finger movement task while "on" medication. Eighteen participants moved faster, 10 moved slower, and 13 were able to maintain the appropriate rate at rates above 2Hz. Clinical measures of laterality, disease severity, and the UPDRS were obtained. There were no significant differences between the more and less affected sides regardless of performance group. Comparison of disease severity, tremor, and rigidity among performance groups revealed no significant differences. Comparison of posture and postural instability scores revealed that the participants that demonstrated hastening had worse posture and postural instability scores. Consideration of movement rate during the clinical evaluation of repetitive finger movement may provide additional insight into varying disease features in persons with PD. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Working memory load affects repetitive behaviour but not cognitive flexibility in adolescent autism spectrum disorder.

    Science.gov (United States)

    Wolff, Nicole; Chmielewski, Witold X; Beste, Christian; Roessner, Veit

    2017-03-16

    Autism spectrum disorder (ASD) is associated with repetitive and stereotyped behaviour, suggesting that cognitive flexibility may be deficient in ASD. A central, yet not examined aspect to understand possible deficits in flexible behaviour in ASD relates (i) to the role of working memory and (ii) to neurophysiological mechanisms underlying behavioural modulations. We analysed behavioural and neurophysiological (EEG) correlates of cognitive flexibility using a task-switching paradigm with and without working memory load in adolescents with ASD and typically developing controls (TD). Adolescents with ASD versus TD show similar performance in task switching with no memory load, indicating that 'pure' cognitive flexibility is not in deficit in adolescent ASD. However performance during task repetition decreases with increasing memory load. Neurophysiological data reflect the pattern of behavioural effects, showing modulations in P2 and P3 event-related potentials. Working memory demands affect repetitive behaviour while processes of cognitive flexibility are unaffected. Effects emerge due to deficits in preparatory attentional processes and deficits in task rule activation, organisation and implementation of task sets when repetitive behaviour is concerned. It may be speculated that the habitual response mode in ASD (i.e. repetitive behaviour) is particularly vulnerable to additional demands on executive control processes.

  16. Repetitive muscle compression reduces vascular mechano-sensitivity and the hyperemic response to muscle contraction.

    Science.gov (United States)

    Messere, A; Turturici, M; Millo, G; Roatta, S

    2017-06-01

    Animal studies have shown that the rapid hyperemic response to external muscle compression undergoes inactivation upon repetitive stimulation, but this phenomenon has never been observed in humans. The aim of the present study was to determine whether 1) the vascular mechano-sensitivity underlying muscle compression-induced hyperemia is inactivated in an inter-stimulus interval (ISI)-dependent fashion upon repetitive stimulation, as suggested by animal studies, and 2) whether such inactivation also attenuates contraction-induced hyperemia. Brachial artery blood flow was measured by echo Doppler sonography in 13 healthy adults in response to 1) single and repetitive cuff muscle compression (CMC) of the forearm (20 CMCs, 1 s ISI); 2) a sequence of CMC delivered at decreasing ISI from 120 to 2 s; and 3) electrically-stimulated contraction of the forearm muscles before and after repetitive CMC. The peak amplitude of hyperemia in response to CMC normalized to baseline decreased from 2.2 ± 0.6 to 1.4 ± 0.4 after repetitive CMC and, in general, was decreased at ISI < 240 s. The peak amplitude of contraction-induced hyperemia was attenuated after as compared to before repeated CMC (1.7 ± 0.4 and 2.6 ± 0.6, respectively). Mechano-sensitivity of the vascular network can be conditioned by previous mechanical stimulation, and such preconditioning may substantially decrease contraction-induced hyperemia.

  17. Structurally Complex Organization of Repetitive DNAs in the Genome of Cobia (Rachycentron canadum).

    Science.gov (United States)

    Costa, Gideão W W F; Cioffi, Marcelo de B; Bertollo, Luiz A C; Molina, Wagner F

    2015-06-01

    Repetitive DNAs comprise the largest fraction of the eukaryotic genome. They include microsatellites or simple sequence repeats (SSRs), which play an important role in the chromosome differentiation among fishes. Rachycentron canadum is the only representative of the family Rachycentridae. This species has been focused on several multidisciplinary studies in view of its important potential for marine fish farming. In the present study, distinct classes of repetitive DNAs, with emphasis on SSRs, were mapped in the chromosomes of this species to improve the knowledge of its genome organization. Microsatellites exhibited a diversified distribution, both dispersed in euchromatin and clustered in the heterochromatin. The multilocus location of SSRs strengthened the heterochromatin heterogeneity in this species, as suggested by some previous studies. The colocalization of SSRs with retrotransposons and transposons pointed to a close evolutionary relationship between these repetitive sequences. A number of heterochromatic regions highlighted a greater complex organization than previously supposed, harboring a diversity of repetitive elements. In this sense, there was also evidence of colocalization of active genetic regions and different classes of repetitive DNAs in a common heterochromatic region, which offers a potential opportunity for further researches regarding the interaction of these distinct fractions in fish genomes.

  18. Nonword repetition in adults who stutter: The effects of stimuli stress and auditory-orthographic cues.

    Directory of Open Access Journals (Sweden)

    Geoffrey A Coalson

    Full Text Available Adults who stutter (AWS are less accurate in their immediate repetition of novel phonological sequences compared to adults who do not stutter (AWNS. The present study examined whether manipulation of the following two aspects of traditional nonword repetition tasks unmask distinct weaknesses in phonological working memory in AWS: (1 presentation of stimuli with less-frequent stress patterns, and (2 removal of auditory-orthographic cues immediately prior to response.Fifty-two participants (26 AWS, 26 AWNS produced 12 bisyllabic nonwords in the presence of corresponding auditory-orthographic cues (i.e., immediate repetition task, and the absence of auditory-orthographic cues (i.e., short-term recall task. Half of each cohort (13 AWS, 13 AWNS were exposed to the stimuli with high-frequency trochaic stress, and half (13 AWS, 13 AWNS were exposed to identical stimuli with lower-frequency iambic stress.No differences in immediate repetition accuracy for trochaic or iambic nonwords were observed for either group. However, AWS were less accurate when recalling iambic nonwords than trochaic nonwords in the absence of auditory-orthographic cues.Manipulation of two factors which may minimize phonological demand during standard nonword repetition tasks increased the number of errors in AWS compared to AWNS. These findings suggest greater vulnerability in phonological working memory in AWS, even when producing nonwords as short as two syllables.

  19. The algorithm for duration acceleration of repetitive projects considering the learning effect

    Science.gov (United States)

    Chen, Hongtao; Wang, Keke; Du, Yang; Wang, Liwan

    2018-03-01

    Repetitive project optimization problem is common in project scheduling. Repetitive Scheduling Method (RSM) has many irreplaceable advantages in the field of repetitive projects. As the same or similar work is repeated, the proficiency of workers will be correspondingly low to high, and workers will gain experience and improve the efficiency of operations. This is learning effect. Learning effect is one of the important factors affecting the optimization results in repetitive project scheduling. This paper analyzes the influence of the learning effect on the controlling path in RSM from two aspects: one is that the learning effect changes the controlling path, the other is that the learning effect doesn't change the controlling path. This paper proposes corresponding methods to accelerate duration for different types of critical activities and proposes the algorithm for duration acceleration based on the learning effect in RSM. And the paper chooses graphical method to identity activities' types and considers the impacts of the learning effect on duration. The method meets the requirement of duration while ensuring the lowest acceleration cost. A concrete bridge construction project is given to verify the effectiveness of the method. The results of this study will help project managers understand the impacts of the learning effect on repetitive projects, and use the learning effect to optimize project scheduling.

  20. Repetition Enhancement of Amygdala and Visual Cortex Functional Connectivity Reflects Nonconscious Memory for Negative Visual Stimuli.

    Science.gov (United States)

    Kark, Sarah M; Slotnick, Scott D; Kensinger, Elizabeth A

    2016-12-01

    Most studies using a recognition memory paradigm examine the neural processes that support the ability to consciously recognize past events. However, there can also be nonconscious influences from the prior study episode that reflect repetition suppression effects-a reduction in the magnitude of activity for repeated presentations of stimuli-that are revealed by comparing neural activity associated with forgotten items to correctly rejected novel items. The present fMRI study examined the effect of emotional valence (positive vs. negative) on repetition suppression effects. Using a standard recognition memory task, 24 participants viewed line drawings of previously studied negative, positive, and neutral photos intermixed with novel line drawings. For each item, participants made an old-new recognition judgment and a sure-unsure confidence rating. Collapsed across valence, repetition suppression effects were found in ventral occipital-temporal cortex and frontal regions. Activity levels in the majority of these regions were not modulated by valence. However, repetition enhancement of the amygdala and ventral occipital-temporal cortex functional connectivity reflected nonconscious memory for negative items. In this study, valence had little effect on activation patterns but had a larger effect on functional connectivity patterns that were markers of nonconscious memory. Beyond memory and emotion, these findings are relevant to other cognitive and social neuroscientists that utilize fMRI repetition effects to investigate perception, attention, social cognition, and other forms of learning and memory.

  1. Decreased microvascular cerebral blood flow assessed by diffuse correlation spectroscopy after repetitive concussions in mice.

    Science.gov (United States)

    Buckley, Erin M; Miller, Benjamin F; Golinski, Julianne M; Sadeghian, Homa; McAllister, Lauren M; Vangel, Mark; Ayata, Cenk; Meehan, William P; Franceschini, Maria Angela; Whalen, Michael J

    2015-12-01

    Repetitive concussions are associated with long-term cognitive dysfunction that can be attenuated by increasing the time intervals between concussions; however, biomarkers of the safest rest interval between injuries remain undefined. We hypothesize that deranged cerebral blood flow (CBF) is a candidate biomarker for vulnerability to repetitive concussions. Using a mouse model of human concussion, we examined the effect of single and repetitive concussions on cognition and on an index of CBF (CBFi) measured with diffuse correlation spectroscopy. After a single mild concussion, CBFi was reduced by 35±4% at 4 hours (Pconcussions spaced 1 day apart, CBFi was also reduced from preinjury levels 4 hours after each concussion but had returned to preinjury levels by 72 hours after the final concussion. Interestingly, in this repetitive concussion model, lower CBFi values measured both preinjury and 4 hours after the third concussion were associated with worse performance on the Morris water maze assessed 72 hours after the final concussion. We conclude that low CBFi measured either before or early on in the evolution of injury caused by repetitive concussions could be a useful predictor of cognitive outcome.

  2. Sources of Phoneme Errors in Repetition: Perseverative, Neologistic, and Lesion Patterns in Jargon Aphasia

    Directory of Open Access Journals (Sweden)

    Emma Pilkington

    2017-05-01

    Full Text Available This study examined patterns of neologistic and perseverative errors during word repetition in fluent Jargon aphasia. The principal hypotheses accounting for Jargon production indicate that poor activation of a target stimulus leads to weakly activated target phoneme segments, which are outcompeted at the phonological encoding level. Voxel-lesion symptom mapping studies of word repetition errors suggest a breakdown in the translation from auditory-phonological analysis to motor activation. Behavioral analyses of repetition data were used to analyse the target relatedness (Phonological Overlap Index: POI of neologistic errors and patterns of perseveration in 25 individuals with Jargon aphasia. Lesion-symptom analyses explored the relationship between neurological damage and jargon repetition in a group of 38 aphasia participants. Behavioral results showed that neologisms produced by 23 jargon individuals contained greater degrees of target lexico-phonological information than predicted by chance and that neologistic and perseverative production were closely associated. A significant relationship between jargon production and lesions to temporoparietal regions was identified. Region of interest regression analyses suggested that damage to the posterior superior temporal gyrus and superior temporal sulcus in combination was best predictive of a Jargon aphasia profile. Taken together, these results suggest that poor phonological encoding, secondary to impairment in sensory-motor integration, alongside impairments in self-monitoring result in jargon repetition. Insights for clinical management and future directions are discussed.

  3. Genomic Organization and Physical Mapping of Tandemly Arranged Repetitive DNAs in Sterlet (Acipenser ruthenus).

    Science.gov (United States)

    Biltueva, Larisa S; Prokopov, Dimitry Y; Makunin, Alexey I; Komissarov, Alexey S; Kudryavtseva, Anna V; Lemskaya, Natalya A; Vorobieva, Nadezhda V; Serdyukova, Natalia A; Romanenko, Svetlana A; Gladkikh, Olga L; Graphodatsky, Alexander S; Trifonov, Vladimir A

    2017-01-01

    Acipenseriformes represent a phylogenetically basal clade of ray-finned fish characterized by unusual genomic traits, including paleopolyploid states of extant genomes with high chromosome numbers and slow rates of molecular evolution. Despite a high interest in this fish group, only a limited number of studies have been accomplished on the isolation and characterization of repetitive DNA, karyotype standardization is not yet complete, and sex chromosomes are still to be identified. Here, we applied next-generation sequencing and cluster analysis to characterize major fractions of sterlet (Acipenser ruthenus) repetitive DNA. Using FISH, we mapped 16 tandemly arranged sequences on sterlet chromosomes and found them to be unevenly distributed in the genome with a tendency to cluster in particular regions. Some of the satellite DNAs might be used as specific markers to identify individual chromosomes and their paralogs, resulting in the unequivocal identification of at least 18 chromosome pairs. Our results provide an insight into the characteristic genomic distribution of the most common sterlet repetitive sequences. Biased accumulation of repetitive DNAs in particular chromosomes makes them especially interesting for further search for cryptic sex chromosomes. Future studies of these sequences in other acipenserid species will provide new perspectives regarding the evolution of repetitive DNA within the genomes of this fish order. © 2017 S. Karger AG, Basel.

  4. Stimulus repetition and the perception of time: the effects of prior exposure on temporal discrimination, judgment, and production.

    Directory of Open Access Journals (Sweden)

    William J Matthews

    Full Text Available It has been suggested that repeated stimuli have shorter subjective duration than novel items, perhaps because of a reduction in the neural response to repeated presentations of the same object. Five experiments investigated the effects of repetition on time perception and found further evidence that immediate repetition reduces apparent duration, consistent with the idea that subjective duration is partly based on neural coding efficiency. In addition, the experiments found (a no effect of repetition on the precision of temporal discrimination, (b that the effects of repetition disappeared when there was a modest lag between presentations, (c that, across participants, the size of the repetition effect correlated with temporal discrimination, and (d that the effects of repetition suggested by a temporal production task were the opposite of those suggested by temporal judgments. The theoretical and practical implications of these results are discussed.

  5. Patterning crystalline indium tin oxide by high repetition rate femtosecond laser-induced crystallization

    International Nuclear Information System (INIS)

    Cheng, Chung-Wei; Lin, Cen-Ying; Shen, Wei-Chih; Lee, Yi-Ju; Chen, Jenq-Shyong

    2010-01-01

    A method is proposed for patterning crystalline indium tin oxide (c-ITO) patterns on amorphous ITO (a-ITO) thin films by femtosecond laser irradiation at 80 MHz repetition rate followed by chemical etching. In the proposed approach, the a-ITO film is transformed into a c-ITO film over a predetermined area via the heat accumulation energy supplied by the high repetition rate laser beam, and the unirradiated a-ITO film is then removed using an acidic etchant solution. The fabricated c-ITO patterns are observed using scanning electron microscopy and cross-sectional transmission electron microscopy. The crystalline, optical, electrical properties were measured by X-ray diffraction, spectrophotometer, and four point probe station, respectively. The experimental results show that a high repetition rate reduces thermal shock and yields a corresponding improvement in the surface properties of the c-ITO patterns.

  6. Surface damage characteristics of CFC and tungsten with repetitive ELM-like pulsed plasma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Y., E-mail: ykikuchi@eng.u-hyogo.ac.jp [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, 671-2280 Hyogo (Japan); Nishijima, D. [Center for Energy Research, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0417 (United States); Nakatsuka, M.; Ando, K.; Higashi, T.; Ueno, Y.; Ishihara, M.; Shoda, K.; Nagata, M. [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, 671-2280 Hyogo (Japan); Kawai, T.; Ueda, Y. [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Fukumoto, N. [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, 671-2280 Hyogo (Japan); Doerner, R.P. [Center for Energy Research, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0417 (United States)

    2011-08-01

    Surface damage of carbon fiber composite (CFC) and tungsten (W) due to repetitive ELM-like pulsed plasma irradiation has been investigated by using a magnetized coaxial plasma gun. CX2002U CFC and stress-relieved W samples were exposed to repetitive pulsed deuterium plasmas with duration of {approx}0.5 ms, incident ion energy of {approx}30 eV, and surface absorbed energy density of {approx}0.3-0.7 MJ/m{sup 2}. Bright spots on a CFC surface during pulsed plasma exposures were clearly observed with a high-speed camera, indicating a local surface heating. No melting of a W surface was observed under a single plasma pulse exposure at energy density of {approx}0.7 MJ/m{sup 2}, although cracks were formed. Cracking of the W surface grew with repetitive pulsed plasma exposures. Subsequently, the surface melted due to localized heat absorption.

  7. A vacuum-sealed, gigawatt-class, repetitively pulsed high-power microwave source

    Science.gov (United States)

    Xun, Tao; Fan, Yu-wei; Yang, Han-wu; Zhang, Zi-cheng; Chen, Dong-qun; Zhang, Jian-de

    2017-06-01

    A compact L-band sealed-tube magnetically insulated transmission line oscillator (MILO) has been developed that does not require bulky external vacuum pump for repetitive operations. This device with a ceramic insulated vacuum interface, a carbon fiber array cathode, and non-evaporable getters has a base vacuum pressure in the low 10-6 Pa range. A dynamic 3-D Monte-Carlo model for the molecular flow movement and collision was setup for the MILO chamber. The pulse desorption, gas evolution, and pressure distribution were exactly simulated. In the 5 Hz repetition rate experiments, using a 600 kV diode voltage and 48 kA beam current, the average radiated microwave power for 25 shots is about 3.4 GW in 45 ns pulse duration. The maximum equilibrium pressure is below 4.0 × 10-2 Pa, and no pulse shortening limitations are observed during the repetitive test in the sealed-tube condition.

  8. The effect of music on repetitive disruptive vocalizations of persons with dementia.

    Science.gov (United States)

    Casby, J A; Holm, M B

    1994-10-01

    This study examined the effect of classical music and favorite music on the repetitive disruptive vocalizations of long-term-care facility (LTCF) residents with dementia of the Alzheimer's type (DAT). Three subjects diagnosed with DAT who had a history of repetitive disruptive vocalizations were selected for the study. Three single-subject withdrawal designs (ABA, ACA, and ABCA) were used to assess subjects' repetitive disruptive vocalizations during each phase: no intervention (A); relaxing, classical music (B); and favorite music (C). Classical music and favorite music significantly decreased the number of vocalizations in two of the three subjects (p < .05). These findings support a method that was effective in decreasing the disruptive vocalization pattern common in those with DAT in the least restrictive manner, as mandated by the Omnibus Budget Reconciliation Act of 1987.

  9. Selective attention modulates visual and haptic repetition priming: effects in aging and Alzheimer's disease.

    Science.gov (United States)

    Ballesteros, Soledad; Reales, José M; Mayas, Julia; Heller, Morton A

    2008-08-01

    In two experiments, we examined the effect of selective attention at encoding on repetition priming in normal aging and Alzheimer's disease (AD) patients for objects presented visually (experiment 1) or haptically (experiment 2). We used a repetition priming paradigm combined with a selective attention procedure at encoding. Reliable priming was found for both young adults and healthy older participants for visually presented pictures (experiment 1) as well as for haptically presented objects (experiment 2). However, this was only found for attended and not for unattended stimuli. The results suggest that independently of the perceptual modality, repetition priming requires attention at encoding and that perceptual facilitation is maintained in normal aging. However, AD patients did not show priming for attended stimuli, or for unattended visual or haptic objects. These findings suggest an early deficit of selective attention in AD. Results are discussed from a cognitive neuroscience approach.

  10. Investigating the work-family conflict and health link: Repetitive thought as a mechanism.

    Science.gov (United States)

    Davis, Kelly D; Gere, Judith; Sliwinski, Martin J

    2017-10-01

    Research is needed to investigate mechanisms linking work-family conflict to poor health in working adults. We took a novel approach to build on extant studies by testing a potential mechanism in these associations - repetitive thought. Data came from a sample of 203 partnered working adults. There were significant direct effects of work-family conflict with lower life satisfaction, positive affect, and perceived health as well as greater fatigue. As for total effects, work-family conflict was significantly associated with all health outcomes - life satisfaction, positive affect, negative affect, fatigue, perceived health, and chronic health conditions - in the expected directions through repetitive thought. This study provides support that repetitive thought is one potential mechanism of how work-family conflict can take a toll on psychological and physical health. Findings are discussed in relation to improving workplace policies to improve the health of working adults managing work-family conflict. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Maximal Repetitions in Written Texts: Finite Energy Hypothesis vs. Strong Hilberg Conjecture

    Directory of Open Access Journals (Sweden)

    Łukasz Dębowski

    2015-08-01

    Full Text Available The article discusses two mutually-incompatible hypotheses about the stochastic mechanism of the generation of texts in natural language, which could be related to entropy. The first hypothesis, the finite energy hypothesis, assumes that texts are generated by a process with exponentially-decaying probabilities. This hypothesis implies a logarithmic upper bound for maximal repetition, as a function of the text length. The second hypothesis, the strong Hilberg conjecture, assumes that the topological entropy grows as a power law. This hypothesis leads to a hyperlogarithmic lower bound for maximal repetition. By a study of 35 written texts in German, English and French, it is found that the hyperlogarithmic growth of maximal repetition holds for natural language. In this way, the finite energy hypothesis is rejected, and the strong Hilberg conjecture is partly corroborated.

  12. Physiological responses to four hours of low-level repetitive work

    DEFF Research Database (Denmark)

    Garde, A Helene; Hansen, Åse Marie; Jensen, Bente R

    2003-01-01

    OBJECTIVES: The study investigated physiological responses to 4 hours of standardized low-level repetitive work. It was hypothesized that accumulative effects not observed after 1 hour could be found after 4 hours of repetitive work. METHODS: Ten healthy women performed intermittent (5 seconds + 5...... muscle activity during a mental reference task with low exerted force indicated attention-related muscle activity. Finally, it was indicated that repetitive work including high demands for attention is performed at the expense of the precision of the exerted force....... seconds) handgrip contractions at 10% of the maximal voluntary contraction combined with mental demands for concentration and attention. Muscle activity in the working forearm muscles, cardiovascular responses, and concentrations of biomarkers in biological fluids were recorded along with exerted force...

  13. A high-repetition rate LWFA for studies of laser propagation and electron generation

    Science.gov (United States)

    He, Zhaohan; Easter, James; Hou, Bixue; Krushelnick, Karl; Nees, John; Thomas, Alec

    2010-11-01

    Advances in ultrafast optics today have enabled laser systems to deliver ever shorter and more intense pulses. When focused, such laser pulses can easily exceed relativistic intensities where the wakefield created by the strong laser electric field can be used to accelerate electrons. Laser wakefield acceleration of electrons holds promise for future compact electron accelerators or drivers of other radiation sources in many scientific, medical and engineering applications. We present experimental studies of laser wakefield acceleration using the λ-cubed laser at the University of Michigan -- a table-top high-power laser system operating at 500 Hz repetition rate. The high repetition rate allows statistical studies of laser propagation and electron acceleration which are not accessible with typical sub-0.1 Hz repetition rate systems. In addition, we compare the experiments with particle-in-cell simulations using the code OSIRIS.

  14. Incremental learning of perceptual and conceptual representations and the puzzle of neural repetition suppression.

    Science.gov (United States)

    Gotts, Stephen J

    2016-08-01

    Incremental learning models of long-term perceptual and conceptual knowledge hold that neural representations are gradually acquired over many individual experiences via Hebbian-like activity-dependent synaptic plasticity across cortical connections of the brain. In such models, variation in task relevance of information, anatomic constraints, and the statistics of sensory inputs and motor outputs lead to qualitative alterations in the nature of representations that are acquired. Here, the proposal that behavioral repetition priming and neural repetition suppression effects are empirical markers of incremental learning in the cortex is discussed, and research results that both support and challenge this position are reviewed. Discussion is focused on a recent fMRI-adaptation study from our laboratory that shows decoupling of experience-dependent changes in neural tuning, priming, and repetition suppression, with representational changes that appear to work counter to the explicit task demands. Finally, critical experiments that may help to clarify and resolve current challenges are outlined.

  15. Design of a low emittance and high repetition rate S-band photoinjector

    Science.gov (United States)

    Han, Jang-Hui

    2014-09-01

    As an electron beam injector of X-ray free-electron lasers (FELs), photoinjectors have been developed for the past few decades. Such an injector starting with a photocathode RF gun provides high brightness beams and therefore it is being adopted as an injector of X-ray FELs. In this paper we show how to improve photoinjector performance in terms of emittance and repetition rates by means of injector components optimization, especially with the gun. Transverse emittance at the end of an injector is reduced by optimizing the gun design, gun solenoid position, and accelerating section position. The repetition rate of an injector mainly depends on the gun. It is discussed that a repetition rate of 1 kHz at a normal-conducting S-band photoinjector is feasible by adopting a coaxial RF coupler and improving cooling-water channels surrounding the gun.

  16. Primary power supply of repetitive pulsed intense current accelerator charged by capacitance of energy store

    International Nuclear Information System (INIS)

    Chen Jun; Yang Jianhua; Shu Ting; Zhang Jiande; Zhou Xiang; Wen Jianchun

    2008-01-01

    The primary power supply of repetitive pulsed intense current accelerator charged by capacitance of energy store is studied. The principle of primary power supply circuit and its time diagram of switches are presented. The circuit is analyzed and some expressions are got, especially, the usable voltage scope of capacitance of energy store, and the correlation between the parameters of circuit and time delay, which is between the turn-on of the charging circuit of capacitance of energy store and the circuit of recuperation. The time delay of 256 x 256 lookup table is made with the instruction of theory and the simulation of the actual parameters of circuits. The table is used by the control program to control the repetitive operating of the actual pulsed intense current accelerator. Finally, some conclusions of the primary power supply of repetitive pulsed intense current accelerator charged by capacitance of energy store are got. (authors)

  17. Cortical activity and children's rituals, habits and other repetitive behavior: a visual P300 study.

    Science.gov (United States)

    Evans, David W; Maliken, Ashley

    2011-10-10

    This study examines the link between children's repetitive, ritualistic, behavior and cortical brain activity. Twelve typically developing children between the ages of 6 and 12 years were administered two visual P300, oddball tasks with a 32-electrode electroencephalogram (EEG) system. One of the oddball tasks was specifically designed to reflect sensitivity to asymmetry, a phenomenon common in children and in a variety of disorders involving compulsive behavior. Parents completed the Childhood Routines Inventory. Children's repetitive, compulsive-like behaviors were strongly associated with faster processing of an asymmetrical target stimulus, even when accounting for their P300 latencies on a control task. The research punctuates the continuity between observed brain-behavior links in clinical disorders such as OCD and autism spectrum disorders, and normative variants of repetitive behavior. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Oxotremorine treatment reduces repetitive behaviors in BTBR T+ tf/J mice

    Directory of Open Access Journals (Sweden)

    Dionisio A. Amodeo

    2014-08-01

    Full Text Available Repetitive behaviors with restricted interests is one of the core criteria for the diagnosis of autism spectrum disorder (ASD. Current pharmacotherapies that target the dopaminergic or serotonergic systems have limited effectiveness in treating repetitive behaviors. Previous research has demonstrated that administration of muscarinic cholinergic receptor (mAChR antagonists can exacerbate motor stereotypies while mAChR agonists reduce stereotypies. The present study determined whether the mAChR agonist, oxotremorine affected repetitive behaviors in the BTBR T+ tf/J (BTBR mouse model of autism. To test the effects of oxotremorine on repetitive behaviors, marble burying and grooming behavior were measured in BTBR mice and compared to that in C57BL/6J (B6 mice. The effects of oxotremorine on locomotor activity was also measured. Thirty minutes before each test, mice received an intraperitoneal injection of saline, 0.001 mg or 0.01 mg of oxotremorine methiodide. Saline- treated BTBR mice exhibited increased marble burying and self-grooming behavior compared to that of saline-treated B6 mice. Oxotremorine significantly reduced marble burying and self-grooming behavior in BTBR mice, but had no significant effect in B6 mice. In addition, oxotremorine did not affect locomotor activity in BTBR mice, but significantly reduced locomotor activity in B6 mice at the 0.01 mg dose. These findings demonstrate that activation of mAChRs reduces repetitive behavior in the BTBR mouse and suggest that treatment with a mAChR agonist may be effective in reducing repetitive behaviors in ASD.

  19. Repetitive cryotherapy attenuates the in vitro and in vivo mononuclear cell activation response.

    Science.gov (United States)

    Lindsay, Angus; Othman, Mohd Izani; Prebble, Hannah; Davies, Sian; Gieseg, Steven P

    2016-07-01

    What is the central question of this study? Acute and repetitive cryotherapy are routinely used to accelerate postexercise recovery, although the effect on resident immune cells and repetitive exposure has largely been unexplored and neglected. What is the main finding and its importance? Using blood-derived mononuclear cells and semi-professional mixed martial artists, we show that acute and repetitive cryotherapy reduces the in vitro and in vivo T-cell and monocyte activation response whilst remaining independent of the physical performance of elite athletes. We investigated the effect of repetitive cryotherapy on the in vitro (cold exposure) and in vivo (cold water immersion) activation of blood-derived mononuclear cells following high-intensity exercise. Single and repeated cold exposure (5°C) of a mixed cell culture (T cells and monocytes) was investigated using in vitro tissue culture experimentation for total neopterin production (neopterin plus 7,8-dihydroneopterin). Fourteen elite mixed martial art fighters were also randomly assigned to either a cold water immersion (15 min at 10°C) or passive recovery protocol, which they completed three times per week during a 6 week training camp. Urine was collected and analysed for neopterin and total neopterin three times per week, and perceived soreness, fatigue, physical performance (broad jump, push-ups and pull-ups) and training performance were also assessed. Single and repetitive cold exposure significantly (P cryotherapy attenuates in vitro T-cell and monocyte activation. This may explain the disparity in in vivo neopterin and total neopterin between cold water immersion and passive recovery following repetitive exposure during a high-intensity physical impact sport that remains independent of physical performance. © 2016 The Authors. Experimental Physiology © 2016 The Physiological Society.

  20. Fatigue effects upon sticking region and electromyography in a six-repetition maximum bench press.

    Science.gov (United States)

    van den Tillaar, Roland; Saeterbakken, Atle Hole

    2013-01-01

    The aim of the study was to examine the sticking region and concomitant neuromuscular activation of the prime movers during six-repetition maximum (RM) bench pressing. We hypothesised that both peak velocities would decrease and that the electromyography (EMG) of the prime movers (deltoid, major pectoralis and triceps) would increase during the pre-sticking and sticking region during the six repetitions due to fatigue. Thirteen resistance-trained males (age 22.8 ± 2.2 years, stature 1.82 ± 0.06 m, body mass 83.4 ± 7.6 kg) performed 6-RM bench presses. Barbell kinematics and EMG activity of pectoralis major, deltoid anterior, and triceps brachii during the pre-, sticking and post-sticking region of each repetition in a 6-RM bench press were analysed. For both the sticking as the post-sticking region, the time increased significantly from the first to the sixth repetition. Vertical barbell height at the start of sticking region was lower, while the height at the end of the sticking region and post-sticking region did not change during the six repetitions. It was concluded that in 6-RM bench pressing performance, the sticking region is a poor mechanical force region due to the unchanged barbell height at the end of the sticking region. Furthermore, when fatigue occurs, the pectoralis and the deltoid muscles are responsible for surpassing the sticking region as indicated by their increased activity during the pre- and sticking region during the six-repetitions bench press.

  1. EFEKTIVITAS MODEL PEMBELAJARAN AUDITORY INTELLECTUALLY REPETITION (AIR TERHADAP PEMAHAMAN SISWA PADA KONSEP ENERGI DALAM

    Directory of Open Access Journals (Sweden)

    S. Linuwih

    2014-07-01

    Full Text Available Telah dilakukan pembelajaran fisika melalui penerapan model pembelajaran Auditory Intellectually Repetition (AIR pada pokok bahasan konsep energi dalam. Tujuan penelitian ini untuk mengetahui peningkatan pemahaman konsep siswa dan efektivitas model pembelajaran Auditory Intellectually Repetition (AIR terhadap pemahaman siswa pada konsep energi dalam. Penelitian ini menggunakan metode penelitian eksperimen kependidikan (educational experiment research, dengan rancangan pre test-post test control group design. Subjek penelitian adalah dua kelompok belajar yang terdiri atas 32 siswa (eksperimen dan 32 siswa (kontrol kelas XI IPA di SMA N 2 Ungaran tahun ajaran 2013/2014. Data dianalisis menggunakan uji gain dan uji t. Hasil penelitian menunjukkan adanya peningkatan pemahaman konsep siswa dan hasil belajar kognitif siswa. Berdasarkan hasil analisis dapat disimpulkan bahwa penerapan model pembelajaran Auditory Intellectually Repetition (AIR dalam pembelajaran fisika SMA efektif untuk meningkatkan pemahaman konsep siswa.ABSTRACTThe physics learning on concept of the internal energy was carried out through application of Auditory Intellectually Repetition (AIR learning model. This study aimed to determining the improvement of students’ concept understanding and the effectiveness of Auditory Intellectually Repetition (AIR learning model on students’ understanding of the internal energy concept. The research used educational experiment research with pre test-post test control group design. The subject of research consisted of 32 students in eksperimental group and 32 students in control group of XI IPA SMA N 2 Ungaran, academic year 2013/2014. The data were analyzed by using gain test and t test. The result showed that there was an increase of students’ concept understanding and the outcome of students’ cognitive learning. Based on the result, it can be concluded that the application of Auditory Intellectually Repetition (AIR learning model in

  2. Advances in high repetition rate, ultra-short, gigawatt laser systems for time-resolved spectroscopy

    International Nuclear Information System (INIS)

    DiMauro, L.F.

    1991-01-01

    The objective of this article is to emphasize the current advances in the development of high-repetition rate amplifier pumps. Although this review highlights amplifier pump development, any recent data from achieved outputs via the tunable amplifier section is also discussed. The first section describes desirable parameters attributable to the pump amplifier while the rest of the article deals with specific examples for various options. The pump amplifiers can be characterized into two distinct classes; those achieving operation in the hundred hertz regime and those performing at repetition rates ≥1kHz. 23 refs., 4 figs

  3. High-power pre-chirp managed amplification of femtosecond pulses at high repetition rates

    International Nuclear Information System (INIS)

    Liu, Yang; Li, Wenxue; Zhao, Jian; Bai, Dongbi; Luo, Daping; Zeng, Heping

    2015-01-01

    Femtosecond pulses at 250 MHz repetition rate from a mode-locked fiber laser are amplified to high power in a pre-chirp managed amplifier. The experimental strategy offers a potential towards high-power ultrashort laser pulses at high repetition rates. By investigating the laser pulse evolution in the amplification processes, we show that self-similar evolution, finite gain bandwidth and mode instabilities determine pulse characteristics in different regimes. Further average power scaling is limited by the mode instabilities. Nevertheless, this laser system enables us to achieve sub-50 fs pulses with an average power of 93 W. (letter)

  4. Comparison on different repetition rate locking methods in Er-doped fiber laser

    Science.gov (United States)

    Yang, Kangwen; Zhao, Peng; Luo, Jiang; Huang, Kun; Hao, Qiang; Zeng, Heping

    2018-05-01

    We demonstrate a systematic comparative research on the all-optical, mechanical and opto-mechanical repetition rate control methods in an Er-doped fiber laser. A piece of Yb-doped fiber, a piezoelectric transducer and an electronic polarization controller are simultaneously added in the laser cavity as different cavity length modulators. By measuring the cavity length tuning ranges, the output power fluctuations, the temporal and frequency repetition rate stability, we show that all-optical method introduces the minimal disturbances under current experimental condition.

  5. PENGARUH MODEL PEMBELAJARAN AUDITORY, INTELLECTUALLY, AND REPETITION TERHADAP KEMAMPUAN PEMAHAMAN KONSEP DI SMP PUSTEK SERPONG

    Directory of Open Access Journals (Sweden)

    Selviani Fitri

    2016-09-01

    Full Text Available This research aims to know the effect of learning model of Auditory, Intellectually, and Repetition (AIR about cube concept comprehension to students' VIII grade at SMP Pustek Serpong. Kind of the research is experiment quasi research. The research instrument that used is analysis question pretest and postest. The data analyze by using normality test, homogenity test, and t-test. The result of the research show that there is the different ability of cube concept comprehension among students' who gave air learning model with convensional learning model. Keywords: Model Pembelajaran Auditory Intellectually and Repetition (AIR, concept comprehension

  6. Dual-Comb Coherent Raman Spectroscopy with Lasers of 1-GHz Pulse Repetition Frequency

    OpenAIRE

    Mohler, Kathrin J.; Bohn, Bernhard J.; Yan, Ming; Hänsch, Theodor W.; Picqué, Nathalie

    2016-01-01

    We extend the technique of multiplex coherent Raman spectroscopy with two femtosecond mode-locked lasers to oscillators of a pulse repetition frequency of 1 GHz. We demonstrate spectra of liquids, which span 1100 cm$^{-1}$ of Raman shifts. At a resolution of 6 cm$^{-1}$, their measurement time may be as short as 5 microseconds for a refresh rate of 2 kHz. The waiting period between acquisitions is improved ten-fold compared to previous experiments with two lasers of 100-MHz repetition frequen...

  7. Dual-comb coherent Raman spectroscopy with lasers of 1-GHz pulse repetition frequency.

    Science.gov (United States)

    Mohler, Kathrin J; Bohn, Bernhard J; Yan, Ming; Mélen, Gwénaëlle; Hänsch, Theodor W; Picqué, Nathalie

    2017-01-15

    We extend the technique of multiplex coherent Raman spectroscopy with two femtosecond mode-locked lasers to oscillators of a pulse repetition frequency of 1 GHz. We demonstrate a spectra of liquids, which span 1100  cm-1 of Raman shifts. At a resolution of 6  cm-1, their measurement time may be as short as 5 μs for a refresh rate of 2 kHz. The waiting period between acquisitions is improved 10-fold compared to previous experiments with two lasers of 100-MHz repetition frequencies.

  8. Cognitive-behavioral therapy for childhood repetitive behavior disorders: tic disorders and trichotillomania.

    Science.gov (United States)

    Flessner, Christopher A

    2011-04-01

    This article provides an overview of cognitive-behavioral therapy (CBT) for repetitive behavior disorders. Because tic disorders and trichotillomania are the most often studied and most debilitating of these conditions, this article focuses on the efficacy of CBT for these 2 conditions. An overview of CBT for children presenting with these concerns is provided. This review focuses particularly on habit reversal training, which is at the core of most CBT-based interventions. Two recent empirical studies on the immense potential of CBT in treating childhood repetitive behavior disorders and future areas of research are also discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Methylation patterns of repetitive DNA sequences in germ cells of Mus musculus.

    Science.gov (United States)

    Sanford, J; Forrester, L; Chapman, V; Chandley, A; Hastie, N

    1984-03-26

    The major and the minor satellite sequences of Mus musculus were undermethylated in both sperm and oocyte DNAs relative to the amount of undermethylation observed in adult somatic tissue DNA. This hypomethylation was specific for satellite sequences in sperm DNA. Dispersed repetitive and low copy sequences show a high degree of methylation in sperm DNA; however, a dispersed repetitive sequence was undermethylated in oocyte DNA. This finding suggests a difference in the amount of total genomic DNA methylation between sperm and oocyte DNA. The methylation levels of the minor satellite sequences did not change during spermiogenesis, and were not associated with the onset of meiosis or a specific stage in sperm development.

  10. Effects of cue frequency and repetition on prospective memory: an ERP investigation.

    Science.gov (United States)

    Wilson, Jennifer; Cutmore, Tim R H; Wang, Ya; Chan, Raymond C K; Shum, David H K

    2013-11-01

    Prospective memory involves the formation and completion of delayed intentions and is essential for independent living. In this study (n = 33), event-related potentials (ERPs) were used to systematically evaluate the effects of PM cue frequency (10% versus 30%) and PM cue repetition (high versus low) on ERP modulations. PM cues elicited prospective positivity and frontal positivity but not N300, perhaps due to the semantic nature of the task. Results of this study revealed an interesting interaction between PM cue frequency and PM cue repetition for prospective positivity and frontal positivity, highlighting the importance of taking both factors into account when designing future studies. © 2013.

  11. High-q microring resonator with narrow free spectral range for pulse repetition rate multiplication

    DEFF Research Database (Denmark)

    Pu, Minhao; Ji, Hua; Frandsen, Lars Hagedorn

    2009-01-01

    We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz.......We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz....

  12. Risk of shoulder tendinitis in relation to shoulder loads in monotonous repetitive work

    DEFF Research Database (Denmark)

    Frost, P.; Bonde, J. P.; Mikkelsen, S.

    2002-01-01

    BACKGROUND: Few studies relate the occurrence of shoulder disorders to quantified ergonomic exposures. This study evaluates the hypothesis that shoulder loads in repetitive work might contribute to the occurrence of shoulder tendinitis. METHODS: This is a cross-sectional study of 1961 workers...... in repetitive work and 782 referents. Shoulder loads were quantified at task level and measures of exposures were assigned based on task distribution. Symptoms in combination with clinical criteria defined shoulder tendinitis. RESULTS: The prevalence of shoulder tendinitis was higher among exposed workers...

  13. Repetitive plasma opening switch for powerful high-voltage pulse generators

    International Nuclear Information System (INIS)

    Dolgachev, G.I.; Zakatov, L.P.; Nitishinskii, M.S.; Ushakov, A.G.

    1998-01-01

    Results are presented of experimental studies of plasma opening switches that serve to sharpen the pulses of inductive microsecond high-voltage pulse generators. It is demonstrated that repetitive plasma opening switches can be used to create super-powerful generators operating in a quasi-continuous regime. An erosion switching mechanism and the problem of magnetic insulation in repetitive switches are considered. Achieving super-high peak power in plasma switches makes it possible to develop new types of high-power generators of electron beams and X radiation. Possible implementations and the efficiency of these generators are discussed

  14. Contrasting the Chromosomal Organization of Repetitive DNAs in Two Gryllidae Crickets with Highly Divergent Karyotypes.

    Directory of Open Access Journals (Sweden)

    Octavio M Palacios-Gimenez

    Full Text Available A large percentage of eukaryotic genomes consist of repetitive DNA that plays an important role in the organization, size and evolution. In the case of crickets, chromosomal variability has been found using classical cytogenetics, but almost no information concerning the organization of their repetitive DNAs is available. To better understand the chromosomal organization and diversification of repetitive DNAs in crickets, we studied the chromosomes of two Gryllidae species with highly divergent karyotypes, i.e., 2n(♂ = 29,X0 (Gryllus assimilis and 2n = 9, neo-X1X2Y (Eneoptera surinamensis. The analyses were performed using classical cytogenetic techniques, repetitive DNA mapping and genome-size estimation. Conserved characteristics were observed, such as the occurrence of a small number of clusters of rDNAs and U snDNAs, in contrast to the multiple clusters/dispersal of the H3 histone genes. The positions of U2 snDNA and 18S rDNA are also conserved, being intermingled within the largest autosome. The distribution and base-pair composition of the heterochromatin and repetitive DNA pools of these organisms differed, suggesting reorganization. Although the microsatellite arrays had a similar distribution pattern, being dispersed along entire chromosomes, as has been observed in some grasshopper species, a band-like pattern was also observed in the E. surinamensis chromosomes, putatively due to their amplification and clustering. In addition to these differences, the genome of E. surinamensis is approximately 2.5 times larger than that of G. assimilis, which we hypothesize is due to the amplification of repetitive DNAs. Finally, we discuss the possible involvement of repetitive DNAs in the differentiation of the neo-sex chromosomes of E. surinamensis, as has been reported in other eukaryotic groups. This study provided an opportunity to explore the evolutionary dynamics of repetitive DNAs in two non-model species and will contribute to the

  15. The Adversarial Principle in Prima Facie Judgments of the Legal Thesis Firmed in the Trial of Repetitive Cases

    Directory of Open Access Journals (Sweden)

    Juliana Provedel Cardoso

    2016-10-01

    Full Text Available The present articles objective is to analyse the highly effective adversarial principle from the Constitutional Democratic State of Law and the cooperative process structure. In this sense, an analysis of the repetitive cases model is made with special relevance to the Civil Procedure Codice 2015, put in evidence the preliminary injunction, the repetitive appeals and the resolution incident repetitive demands. With the establishment of the premises, an analysis of the adversarial principle is made on prima facie judgments of the legal thesis firmed in the trial of repetitive cases, in view of the motivation of the court decision (speech of the case and law (speech of the precedents.

  16. Work-related musculoskeletal disorders in the automotive industry due to repetitive work - implications for rehabilitation

    Directory of Open Access Journals (Sweden)

    Quarcoo David

    2010-04-01

    Full Text Available Abstract Background Musculoskeletal disorders (MSDs due to repetitive work are common in manufacturing industries, such as the automotive industry. However, it's still unclear which MSDs of the upper limb are to be expected in the automotive industry in a first aid unit as well as in occupational precaution examinations. It is also unclear which examination method could be performed effectively for practical reasons and under rehabilitation aspects. Additionally, it was to discuss whether the conception of unspecific description for MSDs has advantages or disadvantages in contrast to a precise medical diagnosis. Methods We investigated the health status of two study populations working at two automotive plants in Germany. The first part included 67 consecutive patients who were seen for acute or chronic MSDs at the forearm over a 4-month period at the plants' medical services. Information about patients' working conditions and musculoskeletal symptoms was obtained during a standardized interview, which was followed by a standardized orthopedic-chiropractic physical examination. In the second part, 209 workers with daily exposure to video display terminals (VDT completed a standardized questionnaire and were examined with function-oriented muscular tests on the occasion of their routine occupational precaution medical check-up. Results The majority of the 67 patients seen by the company's medical services were blue-collar works from the assembly lines and trainees rather than white-collar workers from offices. Rates of musculoskeletal complaints were disproportionately higher among experienced people performing new tasks and younger trainees. The most common MSD in this group were disorders of flexor tendons of the forearm. By contrast, among the 209 employees working at VDT disorders of the neck and shoulders were more common than discomfort in the forearm. A positive tendency between restricted rotation of the cervical vertebrae and years

  17. Work-related musculoskeletal disorders in the automotive industry due to repetitive work - implications for rehabilitation.

    Science.gov (United States)

    Spallek, Michael; Kuhn, Walter; Uibel, Stefanie; van Mark, Anke; Quarcoo, David

    2010-04-07

    Musculoskeletal disorders (MSDs) due to repetitive work are common in manufacturing industries, such as the automotive industry. However, it's still unclear which MSDs of the upper limb are to be expected in the automotive industry in a first aid unit as well as in occupational precaution examinations. It is also unclear which examination method could be performed effectively for practical reasons and under rehabilitation aspects. Additionally, it was to discuss whether the conception of unspecific description for MSDs has advantages or disadvantages in contrast to a precise medical diagnosis. We investigated the health status of two study populations working at two automotive plants in Germany. The first part included 67 consecutive patients who were seen for acute or chronic MSDs at the forearm over a 4-month period at the plants' medical services. Information about patients' working conditions and musculoskeletal symptoms was obtained during a standardized interview, which was followed by a standardized orthopedic-chiropractic physical examination. In the second part, 209 workers with daily exposure to video display terminals (VDT) completed a standardized questionnaire and were examined with function-oriented muscular tests on the occasion of their routine occupational precaution medical check-up. The majority of the 67 patients seen by the company's medical services were blue-collar works from the assembly lines and trainees rather than white-collar workers from offices. Rates of musculoskeletal complaints were disproportionately higher among experienced people performing new tasks and younger trainees. The most common MSD in this group were disorders of flexor tendons of the forearm. By contrast, among the 209 employees working at VDT disorders of the neck and shoulders were more common than discomfort in the forearm. A positive tendency between restricted rotation of the cervical vertebrae and years worked at VDT was observed. In addition, only less than 8

  18. Repetitive element transcripts are elevated in the brain of C9orf72 ALS/FTLD patients.

    Science.gov (United States)

    Prudencio, Mercedes; Gonzales, Patrick K; Cook, Casey N; Gendron, Tania F; Daughrity, Lillian M; Song, Yuping; Ebbert, Mark T W; van Blitterswijk, Marka; Zhang, Yong-Jie; Jansen-West, Karen; Baker, Matthew C; DeTure, Michael; Rademakers, Rosa; Boylan, Kevin B; Dickson, Dennis W; Petrucelli, Leonard; Link, Christopher D

    2017-09-01

    Significant transcriptome alterations are detected in the brain of patients with amyotrophic lateral sclerosis (ALS), including carriers of the C9orf72 repeat expansion and C9orf72-negative sporadic cases. Recently, the expression of repetitive element transcripts has been associated with toxicity and, while increased repetitive element expression has been observed in several neurodegenerative diseases, little is known about their contribution to ALS. To assess whether aberrant expression of repetitive element sequences are observed in ALS, we analysed RNA sequencing data from C9orf72-positive and sporadic ALS cases, as well as healthy controls. Transcripts from multiple classes and subclasses of repetitive elements (LINEs, endogenous retroviruses, DNA transposons, simple repeats, etc.) were significantly increased in the frontal cortex of C9orf72 ALS patients. A large collection of patient samples, representing both C9orf72 positive and negative ALS, ALS/FTLD, and FTLD cases, was used to validate the levels of several repetitive element transcripts. These analyses confirmed that repetitive element expression was significantly increased in C9orf72-positive compared to C9orf72-negative or control cases. While previous studies suggest an important link between TDP-43 and repetitive element biology, our data indicate that TDP-43 pathology alone is insufficient to account for the observed changes in repetitive elements in ALS/FTLD. Instead, we found that repetitive element expression positively correlated with RNA polymerase II activity in postmortem brain, and pharmacologic modulation of RNA polymerase II activity altered repetitive element expression in vitro. We conclude that increased RNA polymerase II activity in ALS/FTLD may lead to increased repetitive element transcript expression, a novel pathological feature of ALS/FTLD. © The Author 2017. Published by Oxford University Press.

  19. The Perseverative Thinking Questionnaire (PTQ): validation of a content-independent measure of repetitive negative thinking

    NARCIS (Netherlands)

    Ehring, T.; Zetsche, U.; Weidacker, K.; Wahl, K.; Schönfeld, S.; Ehlers, A.

    2011-01-01

    Repetitive negative thinking (RNT) has been found to be involved in the maintenance of several types of emotional problems and has therefore been suggested to be a transdiagnostic process. However, existing measures of RNT typically focus on a particular disorder-specific content. In this article,

  20. Repetition Blindness Reveals Differences between the Representations of Manipulable and Nonmanipulable Objects

    Science.gov (United States)

    Harris, Irina M.; Murray, Alexandra M.; Hayward, William G.; O'Callaghan, Claire; Andrews, Sally

    2012-01-01

    We used repetition blindness to investigate the nature of the representations underlying identification of manipulable objects. Observers named objects presented in rapid serial visual presentation streams containing either manipulable or nonmanipulable objects. In half the streams, 1 object was repeated. Overall accuracy was lower when streams…

  1. When thinking impairs sleep : Trait, daytime and nighttime repetitive thinking in insomnia

    NARCIS (Netherlands)

    Lancee, J.; Eisma, M.C.; van Zanten, K.B.; Topper, M.

    2017-01-01

    We performed two studies in individuals with sleep problems to investigate trait, daytime, and nighttime repetitive thinking as risk factors for insomnia. In Study 1, 139 participants completed questionnaires on worry, rumination, insomnia, anxiety, depression, and a sleep diary. Trait rumination

  2. Nonword Repetition Priming in Lexical Decision Reverses as a Function of Study Task and Speed Stress

    Science.gov (United States)

    Zeelenberg, Rene; Wagenmakers, Eric-Jan; Shiffrin, Richard M.

    2004-01-01

    The authors argue that nonword repetition priming in lexical decision is the net result of 2 opposing processes. First, repeating nonwords in the lexical decision task results in the storage of a memory trace containing the interpretation that the letter string is a nonword; retrieval of this trace leads to an increase in performance for repeated…

  3. Repetition Suppression in the Left Inferior Frontal Gyrus Predicts Tone Learning Performance.

    Science.gov (United States)

    Asaridou, Salomi S; Takashima, Atsuko; Dediu, Dan; Hagoort, Peter; McQueen, James M

    2016-06-01

    Do individuals differ in how efficiently they process non-native sounds? To what extent do these differences relate to individual variability in sound-learning aptitude? We addressed these questions by assessing the sound-learning abilities of Dutch native speakers as they were trained on non-native tone contrasts. We used fMRI repetition suppression to the non-native tones to measure participants' neuronal processing efficiency before and after training. Although all participants improved in tone identification with training, there was large individual variability in learning performance. A repetition suppression effect to tone was found in the bilateral inferior frontal gyri (IFGs) before training. No whole-brain effect was found after training; a region-of-interest analysis, however, showed that, after training, repetition suppression to tone in the left IFG correlated positively with learning. That is, individuals who were better in learning the non-native tones showed larger repetition suppression in this area. Crucially, this was true even before training. These findings add to existing evidence that the left IFG plays an important role in sound learning and indicate that individual differences in learning aptitude stem from differences in the neuronal efficiency with which non-native sounds are processed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. The hybrid assistive limb (HAL) for Care Support successfully reduced lumbar load in repetitive lifting movements.

    Science.gov (United States)

    Miura, Kousei; Kadone, Hideki; Koda, Masao; Abe, Tetsuya; Kumagai, Hiroshi; Nagashima, Katsuya; Mataki, Kentaro; Fujii, Kengo; Noguchi, Hiroshi; Funayama, Toru; Kawamoto, Hiroaki; Sankai, Yoshiyuki; Yamazaki, Masashi

    2018-05-03

    Work-related low back pain is a serious socioeconomic problem. This study examined whether HAL for Care Support, which is a newly developed wearable robot, would decrease lumbar fatigue and improve lifting performance during repetitive lifting movements. Eighteen healthy volunteers (11 men, 7 women) performed repetitive stoop lifting movements of a cardboard box weighing 12 kg as many times as possible. The first lifting trial was executed without HAL for Care Support, and the second was with it. We evaluated the VAS of lumbar fatigue as the lumbar load and the number of lifts and the lifting time as lifting performance. Without HAL for Care Support, the mean VAS of lumbar fatigue, the number of lifts and lifting time were 68 mm, 60 and 230 s; with HAL for Care Support, they were 51 mm, 87 and 332 s, respectively. Both lifting performance measures were significantly improved by using HAL for Care Support (Fig. 2). A power analysis showed that there was sufficient statistical power for the VAS of lumbar fatigue (0.99), the number of lifts (0.92), and lifting time (0.93). All participants performed their repetitive lifting trials safely. There were no adverse events caused by using HAL for Care Support. In conclusion, the HAL for Care Support can decrease lumbar load and improve the lifting performance during repetitive stoop lifting movements in healthy adults. Copyright © 2018. Published by Elsevier Ltd.

  5. Repetition and masked form priming within and between languages using word and nonword neighbors

    NARCIS (Netherlands)

    Dijkstra, A.F.J.; Hilberink-Schulpen, B.J.H.; Heuven, W.J.B. van

    2010-01-01

    If access to the bilingual lexicon takes place in a language independent way, monolingual repetition and masked form, priming accounts should be directly applicable to bilinguals. We tested such an account (Grainger and Jacobs, 1999) and extended it to explain bilingual ejects from L2 to L1. Dutch

  6. "N"-2 Repetition Costs Depend on Preparation in Trials "n"-1 and "n"-2

    Science.gov (United States)

    Scheil, Juliane; Kleinsorge, Thomas

    2014-01-01

    In task switching, a common result supporting the notion of inhibitory processes as a determinant of switch costs is the occurrence of "n"-2 repetition costs. Evidence suggests that this effect is not affected by preparation. However, the role of preparation on preceding trials has been neglected so far. In this study, evidence for an…

  7. Children's Performance on Pseudoword Repetition Depends on Auditory Trace Quality: Evidence from Event-Related Potentials.

    Science.gov (United States)

    Ceponiene, Rita; Service, Elisabet; Kurjenluoma, Sanna; Cheour, Marie; Naatanen, Risto

    1999-01-01

    Compared the mismatch-negativity (MMN) component of auditory event-related brain potentials to explore the relationship between phonological short-term memory and auditory-sensory processing in 7- to 9-year olds scoring the highest and lowest on a pseudoword repetition test. Found that high and low repeaters differed in MMN amplitude to speech…

  8. Sentence Repetition in Deaf Children with Specific Language Impairment in British Sign Language

    Science.gov (United States)

    Marshall, Chloë; Mason, Kathryn; Rowley, Katherine; Herman, Rosalind; Atkinson, Joanna; Woll, Bencie; Morgan, Gary

    2015-01-01

    Children with specific language impairment (SLI) perform poorly on sentence repetition tasks across different spoken languages, but until now, this methodology has not been investigated in children who have SLI in a signed language. Users of a natural sign language encode different sentence meanings through their choice of signs and by altering…

  9. Generation of plasma X-ray sources via high repetition rate femtosecond laser pulses

    Science.gov (United States)

    Baguckis, Artūras; Plukis, Artūras; Reklaitis, Jonas; Remeikis, Vidmantas; Giniūnas, Linas; Vengris, Mikas

    2017-12-01

    In this study, we present the development and characterization of Cu plasma X-ray source driven by 20 W average power high repetition rate femtosecond laser in ambient atmosphere environment. The peak Cu- Kα photon flux of 2.3 × 109 photons/s into full solid angle is demonstrated (with a process conversion efficiency of 10-7), using pulses with peak intensity of 4.65 × 1014 W/cm2. Such Cu- Kα flux is significantly larger than others found in comparable experiments, performed in air environment. The effects of resonance plasma absorption process, when optimized, are shown to increase measured flux by the factor of 2-3. The relationship between X-ray photon flux and plasma-driving pulse repetition rate is quasi-linear, suggesting that fluxes could further be increased to 1010 photons/s using even higher average powers of driving radiation. These results suggest that to fully utilize the potential of high repetition rate laser sources, novel target material delivery systems (for example, jet-based ones) are required. On the other hand, this study demonstrates that high energy lasers currently used for plasma X-ray sources can be conveniently and efficiently replaced by high average power and repetition rate laser radiation, as a way to increase the brightness of the generated X-rays.

  10. 76 FR 44489 - Medical Devices; Neurological Devices; Classification of Repetitive Transcranial Magnetic...

    Science.gov (United States)

    2011-07-26

    ... is an external device that delivers transcranial repetitive pulsed magnetic fields of sufficient... premarket notification, prior to marketing the device, which contains information about the rTMS system they... significant effect on the human environment. Thus, neither an environmental assessment nor an environmental...

  11. Effects of message repetition and negativity on credibility judgments and political attitudes

    NARCIS (Netherlands)

    Ernst, N.; Kühne, R.; Wirth, W.

    2017-01-01

    Research on the truth effect has demonstrated that statements are rated as more credible when they are repeatedly presented. However, current research indicates that there are limits to the truth effect and that too many repetitions can decrease message credibility. This study investigates whether

  12. A Pilot Study Comparing Two Nonword Repetition Tasks for Use in a Formal Test Battery

    Science.gov (United States)

    Tattersall, Patricia J.; Nelson, Nickola Wolf; Tyler, Ann A.

    2015-01-01

    Two sets of nonwords (with and without true morphemes) were compared for their ability to differentiate students in Grades 1 through 12 with and without language impairment (36 each; N = 72) on a nonword repetition task. Results indicated that either nonword type could contribute to differential diagnosis.

  13. Sands subjected to repetitive vertical loading under zero lateral strain: accumulation models, terminal densities, and settlement

    KAUST Repository

    Chong, Song Hun

    2016-08-09

    Geosystems often experience numerous loading cycles. Plastic strain accumulation during repetitive mechanical loads can lead to shear shakedown or continued shear ratcheting; in all cases, volumetric strains diminish as the specimen evolves towards terminal density. Previously suggested models and new functions are identified to fit plastic strain accumulation data. All accumulation models are formulated to capture terminal density (volumetric strain) and either shakedown or ratcheting (shear strain). Repetitive vertical loading tests under zero lateral strain conditions are conducted using three different sands packed at initially low and high densities. Test results show that plastic strain accumulation for all sands and density conditions can be captured in the same dimensionless plot defined in terms of the initial relative density, terminal density, and ratio between the amplitude of the repetitive load and the initial static load. This observation allows us to advance a simple but robust procedure to estimate the maximum one-dimensional settlement that a foundation could experience if subjected to repetitive loads. © 2016, Canadian Science Publishing. All rights reserved.

  14. [Identification of a repetitive sequence element for DNA fingerprinting in Phytophthora sojae].

    Science.gov (United States)

    Yin, Lihua; Wang, Qinhu; Ning, Feng; Zhu, Xiaoying; Zuo, Yuhu; Shan, Weixing

    2010-04-01

    Establishment of DNA fingerprinting in Phytophthora sojae and an analysis of genetic relationship of Heilongjiang and Xinjiang populations. Bioinformatics tools were used to search repetitive sequences in P. sojae and Southern blot analysis was employed for DNA fingerprinting analysis of P. sojae populations from Heilongjiang and Xinjiang using the identified repetitive sequence. A moderately repetitive sequence was identified and designated as PS1227. Southern blot analysis indicated 34 distinct bands ranging in size from 1.5 kb-23 kb, of which 21 were polymorphic among 49 isolates examined. Analysis of single-zoospore progenies showed that the PS1227 fingerprint pattern was mitotically stable. DNA fingerprinting showed that the P. sojae isolates HP4002, SY6 and GJ0105 of Heilongjiang are genetically identical to DW303, 71228 and 71222 of Xinjiang, respectively. A moderately repetitive sequence designated PS1227 which will be useful for epidemiology and population biology studies of P. sojae was obtained, and a PS1227-based DNA fingerprinting analysis provided molecular evidence that P. sojae in Xinjiang was likely introduced from Heilongjiang.

  15. Repetitive transcranial magnetic stimulation modulates the impact of a negative mood induction

    NARCIS (Netherlands)

    Möbius, M.; Lacomblé, L.M.T.; Meyer, T.; Schutter, D.J.L.G.; Gielkens, T.; Becker, E.S.; Tendolkar, I.; Eijndhoven, P.F.P. van

    2017-01-01

    High frequency repetitive Transcranial Magnetic Stimulation (rTMS) over the left dorsolateral prefrontal cortex (DLPFC) has been found to alleviate depressive symptoms. However, the mechanisms driving these effects are still poorly understood. In the current study, we tested the idea that this

  16. Repetitive DNA: A Versatile Tool for Karyotyping in Festuca pratensis Huds

    Czech Academy of Sciences Publication Activity Database

    Křivánková, Anna; Kopecký, David; Stočes, Štěpán; Doležel, Jaroslav; Hřibová, Eva

    2017-01-01

    Roč. 151, č. 2 (2017), s. 96-105 ISSN 1424-8581 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Fluorescence in situ hybridization * Karyotyping * Meadow fescue * Repetitive DNA * Tandem organized repeats Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 1.354, year: 2016

  17. Graph-based clustering and characterization of repetitive sequences in next-generation sequencing data

    Czech Academy of Sciences Publication Activity Database

    Novák, Petr; Neumann, Pavel; Macas, Jiří

    2010-01-01

    Roč. 11, č. 1 (2010), s. 378-389 ISSN 1471-2105 R&D Projects: GA MŠk(CZ) OC10037; GA MŠk(CZ) LC06004 Institutional research plan: CEZ:AV0Z50510513 Keywords : repetitive DNA * plant genome * next generation sequencing Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.028, year: 2010

  18. Category Priming in the Lexical Decision Task and Evidence of Repetition Effects.

    Science.gov (United States)

    Sanza, James

    Semantic priming is the process by which a subject performing a lexical decision task is prepared for a target word through the presentation of a semantically related word. Repetition of a given word at specific intervals is one form of priming that has been shown to reduce subject reaction time in word recognition tasks. A study was conducted to…

  19. Factors Associated with Choking During Meals; a Risk Indicator for Repetitive Fevers in The Elderly Community

    Directory of Open Access Journals (Sweden)

    Takeshi Nishiyama

    2017-04-01

    Full Text Available Background: Choking during meals is a common symptom in the elderly, however the factors associated with it have not been fully clarified. In this study, we examined the factors associated with choking during meals. Methods: The oral health status and practices that promote oral health conditions was surveyed in 1305 community dwelling elderly using a self-administered questionnaire. Eight items including satisfaction with their oral condition, denture fit, chewing ability, tooth brushing frequency, dental visits, exercises to train muscles for chewing and swallowing, choking during meals, and repetitive fever were selected for analysis. Results: 25.1% of the subjects experienced choking during meals, which was significantly associated with repetitive fever occurrence. Differences in satisfaction levels with their oral condition, denture fit, chewing ability, and tooth brushing frequency were observed between groups with and without choking. Age, satisfaction level, and chewing ability were significantly associated with choking during meals. Conclusions: This study demonstrated that choking during meals is a risk indicator for repetitive fever in the elderly living in community settings. Poor chewing ability and dissatisfaction with their oral condition were risk factors associated with choking. These results suggest that training the elderly to eat efficiently and safely and improving oral conditions is necessary for those who suffer from choking during meals to prevent repetitive fever.

  20. Repetitive transcranial magnetic stimulation to improve mood and motor function in Parkinson's disease.

    NARCIS (Netherlands)

    Helmich, R.C.G.; Siebner, H.R.; Bakker, M.; Munchau, A.; Bloem, B.R.

    2006-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that can produce lasting changes in excitability and activity in cortical regions underneath the stimulation coil (local effect), but also within functionally connected cortical or subcortical regions

  1. Tibialis anterior stretch reflex in early stance is suppressed by repetitive transcranial magnetic stimulation

    DEFF Research Database (Denmark)

    Zuur, Abraham T; Christensen, Mark Schram; Sinkjær, Thomas

    2009-01-01

    Abstract A rapid plantar flexion perturbation in the early stance phase of walking elicits a large stretch reflex in tibialis anterior (TA). In this study we use repetitive Transcranial Magnetic Stimulation (rTMS) to test if this response is mediated through a transcortical pathway. TA stretch...

  2. Repetitive Transcranial Magnetic Stimulation to the Primary Motor Cortex Interferes with Motor Learning by Observing

    Science.gov (United States)

    Brown, Liana E.; Wilson, Elizabeth T.; Gribble, Paul L.

    2009-01-01

    Neural representations of novel motor skills can be acquired through visual observation. We used repetitive transcranial magnetic stimulation (rTMS) to test the idea that this "motor learning by observing" is based on engagement of neural processes for learning in the primary motor cortex (M1). Human subjects who observed another person learning…

  3. PI and repetitive control for single phase inverter based on virtual rotating coordinate system

    Science.gov (United States)

    Li, Mengqi; Tong, Yibin; Jiang, Jiuchun; Liang, Jiangang

    2018-03-01

    Microgrid technology developed rapidly and nonlinear loads were connected increasingly. A new control strategy was proposed for single phase inverter when connected nonlinear loads under island condition. PI and repetitive compound controller was realized under synchronous rotating coordinate system and acquired high quality sinusoidal voltage output without voltage spike when loads step changed. Validity and correctness were verified by simulation using MATLAB/Simulink.

  4. High repetition rate, high energy, actively Q-switched all-in-fiber laser

    Science.gov (United States)

    Lecourt, J. B.; Bertrand, A.; Guillemet, S.; Hernandez, Y.; Giannone, D.

    2010-05-01

    We report an actively Q-switched Ytterbium-doped all-in-fibre laser delivering 10ns pulses with high repetition rate (from 100kHz to 1MHz). The laser operation has been validated at three different wavelengths (1040, 1050 and 1064nm). The laser can deliver up to 20Watts average power with an high beam quality (M2 = 1).

  5. Electrode patterning of ITO thin films by high repetition rate fiber laser

    Energy Technology Data Exchange (ETDEWEB)

    Lin, H.K., E-mail: HKLin@mail.npust.edu.tw; Hsu, W.C.

    2014-07-01

    Indium tin oxide (ITO) thin films are deposited on glass substrates using a radio frequency magnetron sputtering system. As-deposited ITO thin film was 100 nm in thickness and a transmittance of ITO film on glass substrate was 79% at 550 nm. Conductive electrodes are then patterned on the ITO films using a high repetition rate fiber laser system followed by a wet chemical etching process. The electrical, optical and structural properties of the patterned samples are evaluated by means of a four-point probe technique, spectrophotometer, X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results show that the samples annealed with a pulse repetition rate of 150 kHz or 400 kHz have a low sheet resistivity of 21 Ω/□ and a high optical transmittance of 90%. In addition, it is shown that a higher pulse repetition rate reduces both the residual stress and the surface roughness of the patterned specimens. Therefore, the present results suggest that a pulse repetition rate of 400 kHz represents the optimal processing condition for the patterning of crack-free ITO-coated glass substrates with good electrical and optical properties.

  6. Models of Recognition, Repetition Priming, and Fluency : Exploring a New Framework

    Science.gov (United States)

    Berry, Christopher J.; Shanks, David R.; Speekenbrink, Maarten; Henson, Richard N. A.

    2012-01-01

    We present a new modeling framework for recognition memory and repetition priming based on signal detection theory. We use this framework to specify and test the predictions of 4 models: (a) a single-system (SS) model, in which one continuous memory signal drives recognition and priming; (b) a multiple-systems-1 (MS1) model, in which completely…

  7. Study on cerebral activation areas during repetition with functional MRI in normal adults

    International Nuclear Information System (INIS)

    Koseki, Yohju

    2009-01-01

    For cerebral activation of speech areas in functional MRI (f-MRI) study, the usefulness of an optical microphone, which made it possible to perform task repetition at real time during scanning, was examined. Subjects were 25 healthy adults (mean age, 27.1±5.6 years), who consisted of 15 right-handed and 10 left-handed or ambidextrous persons. Tasks comprised repetition of monosyllables, non-words, words and sentences. The repetition tasks were covertly performed during scanning of f-MRI by using an optical microphone. In both the right-handed and non-right-handed groups, activations in the left superior temporal gyrus (sensory speech area) were most frequently observed during all of the tasks. In the right-handed group, activations in the left inferior frontal (motor speech area) and superior temporal gyri were significantly more often observed than those in the right inferior frontal and superior temporal gyri. From an assessment of the laterality index (LI), left-side dominant activation was frequently seen in most of the cerebral regions including sensory and motor speech areas, although right-side and bilateral dominant activations were observed in a few cases. In both groups, activations in regions associated with sensory speech were significantly more often seen than those in regions associated with motor speech. The present predominant activations in regions involved in sensory speech indicate that the optical microphone is useful in f-MRI studies using task repetition. (author)

  8. Stability of Closed Loop Controlled Repetitive Periodic System applied to control of CD-Player

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Andersen, Palle

    2005-01-01

    In this paper a criterion for stability of specific control scheme for handling linear dynamic control systems with repetitive periodic sensor faults is derived. The given system and control scheme are described and defined. By combining these with the lifting technique a necessary and sufficient...

  9. Exploring the Correlates of Impaired Non-Word Repetition in Down Syndrome

    Science.gov (United States)

    Cairns, Peter; Jarrold, Christopher

    2005-01-01

    Non-word repetition, in which participants hear and repeat unfamiliar verbal stimuli, is thought to provide a particularly sensitive measure of verbal short-term memory capacity. However, performance on this task can also be constrained by hearing and speech production skills, and by an individuals' linguistic knowledge. This study examined real…

  10. Repetition and Power Imbalance in Bullying Victimization at School. Data Point. NCES 2018-093

    Science.gov (United States)

    Lessne, Deborah; Yanez, Christine

    2018-01-01

    For the 2014-2015 school year, 20.8 percent of students reported being bullied at school. This report examines these students' experiences of bullying by repetition and power imbalance, two components of the Center for Disease Control and Prevention's (CDC) uniform definition of bullying. The report reviews the association of these components with…

  11. Repetition Priming in Adults with Williams Syndrome: Age-Related Dissociation between Implicit and Explicit Memory

    Science.gov (United States)

    Krinsky-McHale, Sharon J.; Kittler, Phyllis; Brown, W. Ted; Jenkins, Edmund C.; Devenny, Darlynne A.

    2005-01-01

    We examined implicit and explicit memory in adults with Williams syndrome. An age-related dissociation was found; repetition priming (reflecting implicit memory) did not show change with age, but free recall (reflecting explicit memory) was markedly reduced. We also compared the performance of adults with Williams syndrome to adults with Down…

  12. Generation of fast-rise time, repetitive, (sub) nanosecond, high-voltage pulses

    NARCIS (Netherlands)

    Huiskamp, T.; Pemen, A.J.M.

    2017-01-01

    In this contribution we present our fast-rise time nanosecond pulse generator, capable of generating up to 50 kV (positive and negative) rectangular pulses at a repetition rate of up to 1 kHz and with a rise time of less than 200 picoseconds. We focus on the general concepts involved in the design

  13. Spaced Learning Enhances Subsequent Recognition Memory by Reducing Neural Repetition Suppression

    Science.gov (United States)

    Xue, Gui; Mei, Leilei; Chen, Chuansheng; Lu, Zhong-Lin; Poldrack, Russell; Dong, Qi

    2011-01-01

    Spaced learning usually leads to better recognition memory as compared with massed learning, yet the underlying neural mechanisms remain elusive. One open question is whether the spacing effect is achieved by reducing neural repetition suppression. In this fMRI study, participants were scanned while intentionally memorizing 120 novel faces, half…

  14. Effects of Task Repetition on Learners' Attention Orientation in L2 Oral Production

    Science.gov (United States)

    Fukuta, Junya

    2016-01-01

    Task repetition facilitates learners' performance, at least temporarily: Since learners are already familiar with the content of the task at the initial enactment, they are capable of focusing their attention on linguistic form during the following enactment. However, the analysis in previous studies treated various aspects of "form" as…

  15. Restricted and Repetitive Behaviors in Autism Spectrum Disorders: A Review of Research in the Last Decade

    Science.gov (United States)

    Leekam, Susan R.; Prior, Margot R.; Uljarevic, Mirko

    2011-01-01

    Restricted and repetitive behaviors (RRBs) are a core feature of autism spectrum disorders. They constitute a major barrier to learning and social adaptation, but research on their definition, cause, and capacity for change has been relatively neglected. The last decade of research has brought new measurement techniques that have improved the…

  16. Early Morphological Productivity in Hungarian: Evidence from Sentence Repetition and Elicited Production

    Science.gov (United States)

    Gabor, Balint; Lukacs, Agnes

    2012-01-01

    This paper investigates early productivity of morpheme use in Hungarian children aged between 2 ; 1 and 5 ; 3. Hungarian has a rich morphology which is the core marker of grammatical functions. A new method is introduced using the novel word paradigm in a sentence repetition task with masked inflections (i.e. a disguised elicited production task).…

  17. Identification of dose-reduction techniques for BWR and PWR repetitive high-dose jobs

    International Nuclear Information System (INIS)

    Dionne, B.J.; Baum, J.W.

    1984-01-01

    As a result of concern about the apparent increase in collective radiation dose to workers at nuclear power plants, this project will provide information to industry in preplanning for radiation protection during maintenance operations. This study identifies Boiling Water Reactor (BWR) and Pressurized Water Reactor (PWR) repetitive jobs, and respective collective dose trends and dose reduction techniques. 3 references, 2 tables

  18. Acute Alcohol Effects on Repetition Priming and Word Recognition Memory with Equivalent Memory Cues

    Science.gov (United States)

    Ray, Suchismita; Bates, Marsha E.

    2006-01-01

    Acute alcohol intoxication effects on memory were examined using a recollection-based word recognition memory task and a repetition priming task of memory for the same information without explicit reference to the study context. Memory cues were equivalent across tasks; encoding was manipulated by varying the frequency of occurrence (FOC) of words…

  19. Operation and Thermal Modeling of the ISIS H– Source from 50 to 2 Hz Repetition Rates

    CERN Document Server

    Pereira, H; Lettry, J

    2013-01-01

    CERN’s Linac4 accelerator H− ion source, currently under construction, will operate at a 2 Hz repetition rate, with pulse length of 0.5 ms and a beam current of 80 mA. Its reliability must exceed 99 % with a mandatory 3 month uninterrupted operation period. A Penning ion source is successfully operated at ISIS; at 50 Hz repetition rate it reliably provides 55 mA H− pulses of 0.25 ms duration over 1 month. The discharge plasma ignition is very sensitive to the temperatures of the discharge region, especially of its cathode. The investigation by modeling and measurement of operation parameters suitable for arc ignition and H− production at 2 Hz is of paramount importance and must be understood prior to the implementation of discharge ion sources in the Linac4 accelerator. In its original configuration, the ISIS H− source delivers beam only if the repetition rate is above 12.5 Hz, this paper describes the implementation of a temperature control of the discharge region aiming at lower repetition rate op...

  20. Macrophage and tumor cell responses to repetitive pulsed X-ray radiation

    Science.gov (United States)

    Buldakov, M. A.; Tretyakova, M. S.; Ryabov, V. B.; Klimov, I. A.; Kutenkov, O. P.; Kzhyshkowska, J.; Bol'shakov, M. A.; Rostov, V. V.; Cherdyntseva, N. V.

    2017-05-01

    To study a response of tumor cells and macrophages to the repetitive pulsed low-dose X-ray radiation. Methods. Tumor growth and lung metastasis of mice with an injected Lewis lung carcinoma were analysed, using C57Bl6. Monocytes were isolated from a human blood, using CD14+ magnetic beads. IL6, IL1-betta, and TNF-alpha were determined by ELISA. For macrophage phenotyping, a confocal microscopy was applied. “Sinus-150” was used for the generation of pulsed X-ray radiation (the absorbed dose was below 0.1 Gy, the pulse repetition frequency was 10 pulse/sec). The irradiation of mice by 0.1 Gy pulsed X-rays significantly inhibited the growth of primary tumor and reduced the number of metastatic colonies in the lung. Furthermore, the changes in macrophage phenotype and cytokine secretion were observed after repetitive pulsed X-ray radiation. Conclusion. Macrophages and tumor cells had a different response to a low-dose pulsed X-ray radiation. An activation of the immune system through changes of a macrophage phenotype can result in a significant antitumor effect of the low-dose repetitive pulsed X-ray radiation.

  1. Frequency Adaptive Repetitive Control of Grid-Tied Single-Phase PV Inverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2015-01-01

    . This paper thus explores a frequency adaptive repetitive control strategy for grid converters, which employs fractional delay filters in order to adapt to the change of the grid frequency. Case studies with experimental results of a single-phase grid-connected PV inverter system are provided to verify...

  2. A fast 30 kV 5 kHz repetition rate resonant capacitor charger

    NARCIS (Netherlands)

    Beckers, F.J.C.M.; Huiskamp, T.; van Heesch, E.J.M.; Pemen, A.J.M.

    2016-01-01

    A novel circuit topology of a fast 30 kV resonant capacitor charger is presented in this paper. The charger is designed for high repetition rate spark gap based pulsed power modulators. A spark gap can fire spontaneously (pre-firing) during charging of a capacitor bank due to poor dielectric

  3. Functional role of a highly repetitive DNA sequence in anchorage of the mouse genome.

    Science.gov (United States)

    Neuer-Nitsche, B; Lu, X N; Werner, D

    1988-09-12

    The major portion of the eukaryotic genome consists of various categories of repetitive DNA sequences which have been studied with respect to their base compositions, organizations, copy numbers, transcription and species specificities; their biological roles, however, are still unclear. A novel quality of a highly repetitive mouse DNA sequence is described which points to a functional role: All copies (approximately 50,000 per haploid genome) of this DNA sequence reside on genomic Alu I DNA fragments each associated with nuclear polypeptides that are not released from DNA by proteinase K, SDS and phenol extraction. By this quality the repetitive DNA sequence is classified as a member of the sub-set of DNA sequences involved in tight DNA-polypeptide complexes which have been previously shown to be components of the subnuclear structure termed 'nuclear matrix'. From these results it has to be concluded that the repetitive DNA sequence characterized in this report represents or comprises a signal for a large number of site specific attachment points of the mouse genome in the nuclear matrix.

  4. Brief Report: Exploring the Relationship between Sensory Processing and Repetitive Behaviours in Williams Syndrome

    Science.gov (United States)

    Riby, Deborah M.; Janes, Emily; Rodgers, Jacqui

    2013-01-01

    This study explored the relationship between sensory processing abnormalities and repetitive behaviours in children with Williams Syndrome (WS; n = 21). This is a novel investigation bringing together two clinical phenomena for the first time in this neuro-developmental disorder. Parents completed the Sensory Profile (Short Form; Dunn in The…

  5. Anxiety and Repetitive Behaviours in Autism Spectrum Disorders and Williams Syndrome: A Cross-Syndrome Comparison

    Science.gov (United States)

    Rodgers, Jacqui; Riby, Deborah M.; Janes, Emily; Connolly, Brenda; McConachie, Helen

    2012-01-01

    Children with Autism Spectrum Disorder or Williams syndrome are vulnerable to anxiety. The factors that contribute to this risk remain unclear. This study compared anxiety in autism spectrum disorder and Williams Syndrome and examined the relationship between repetitive behaviours and anxiety. Thirty-four children with autism and twenty children…

  6. Electrode patterning of ITO thin films by high repetition rate fiber laser

    International Nuclear Information System (INIS)

    Lin, H.K.; Hsu, W.C.

    2014-01-01

    Indium tin oxide (ITO) thin films are deposited on glass substrates using a radio frequency magnetron sputtering system. As-deposited ITO thin film was 100 nm in thickness and a transmittance of ITO film on glass substrate was 79% at 550 nm. Conductive electrodes are then patterned on the ITO films using a high repetition rate fiber laser system followed by a wet chemical etching process. The electrical, optical and structural properties of the patterned samples are evaluated by means of a four-point probe technique, spectrophotometer, X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results show that the samples annealed with a pulse repetition rate of 150 kHz or 400 kHz have a low sheet resistivity of 21 Ω/□ and a high optical transmittance of 90%. In addition, it is shown that a higher pulse repetition rate reduces both the residual stress and the surface roughness of the patterned specimens. Therefore, the present results suggest that a pulse repetition rate of 400 kHz represents the optimal processing condition for the patterning of crack-free ITO-coated glass substrates with good electrical and optical properties.

  7. Towards a Post-Modern Science Education Curriculum-Discourse: Repetition of a Dream Catcher.

    Science.gov (United States)

    Blades, David W.

    1997-01-01

    Discusses Kierkegaard's idea of repetition as a dynamic conversation between groups that reveals possible changes in a discourse. Describes an instructor's experiences imparting a science education methods course in a Native American school in Saskatchewan, highlighting the conversation between the instructors' past and Native American culture.…

  8. Understanding repetitive travel mode choices in a stable context: A panel study approach

    DEFF Research Database (Denmark)

    Thøgersen, John

    2006-01-01

    It is argued that most travel mode choices are repetitive and made in a stable context. As an example, the everyday use of public transport is analyzed based on a panel survey with a random sample of about 1300 Danish residents interviewed up to three times in the period 1998-2000. The use...

  9. Muscle activation strategies during strength training with heavy loading versus repetitions to failure

    DEFF Research Database (Denmark)

    Sundstrup, Emil; Jakobsen, Markus D; Andersen, Christoffer H

    2012-01-01

    . Electromyographic (EMG) amplitude and median power frequency (MPF) of specific shoulder and neck muscles was analysed and the Borg CR10 scale was used to rate perceived loading immediately after each set of exercise. During the failure set normalized EMG was significantly lower during the first repetition...

  10. Repetitive negative thinking as a transdiagnostic factor in depression and anxiety : A conceptual replication

    NARCIS (Netherlands)

    Drost, Jolijn; van der Does, Willem; van Hemert, Albert M.; Penninx, Brenda W. J. H.; Spinhoven, Philip

    2014-01-01

    Comorbidity among affective disorders is high. Rumination has been found to mediate cross-sectional and prospective relations between anxiety and depressive symptoms in adolescents and adults. We examined whether rumination and Worry, both forms of repetitive negative thinking, also explain the

  11. Repetitive negative thinking as a transdiagnostic factor in depression and anxiety: A conceptual replication

    NARCIS (Netherlands)

    Drost, J.; Van der Does, W.; van Hemert, A.M.; Penninx, B.W.J.H.; Spinhoven, P.

    2014-01-01

    Comorbidity among affective disorders is high. Rumination has been found to mediate cross-sectional and prospective relations between anxiety and depressive symptoms in adolescents and adults. We examined whether rumination and worry, both forms of repetitive negative thinking, also explain the

  12. The Effects of Delayed Reinforcement on Variability and Repetition of Response Sequences

    Science.gov (United States)

    Odum, Amy L.; Ward, Ryan D.; Burke, K. Anne; Barnes, Christopher A.

    2006-01-01

    Four experiments examined the effects of delays to reinforcement on key peck sequences of pigeons maintained under multiple schedules of contingencies that produced variable or repetitive behavior. In Experiments 1, 2, and 4, in the repeat component only the sequence right-right-left-left earned food, and in the vary component four-response…

  13. Material variability and repetitive member factors for the allowable properties of engineered wood products

    Science.gov (United States)

    Steve Verrill; David E. Kretschmann

    2009-01-01

    It has been argued that repetitive member allowable property adjustments should be larger for high-variability materials than for low-variability materials. We report analytic calculations and simulations that suggest that the order of such adjustments should be reversed, that is, given the manner in which allowable properties are currently calculated, as the...

  14. GPI-repetitive control for linear systems with parameter uncertainty / variation

    Directory of Open Access Journals (Sweden)

    John A. Cortés-Romero

    2015-01-01

    Full Text Available Robust repetitive control problems for uncertain linear systems have been considered by different approaches. This article proposes the use of Repetitive Control and Generalized Proportional Integral (GPI Control in a complementary fashion. The conditioning and coupling of these techniques has been done in a time discrete context. Repetitive control is a control technique, based on the internal model principle, which yields perfect asymptotic tracking and rejection of periodic signals. On the other hand, GPI control is established as a robust linear control system design technique that is able to reject structured time polynomial additive perturbation, in particular, parameter uncertainty that can be locally approximated by time polynomial signal. GPI control provides a suitable stability and robustness conditions for the proper Repetitive Control operation. A stability analysis is presented under the frequency response framework using plant samples for different parameter uncertainty conditions. We carry out some comparative stability analysis with other complementary control approaches that has been effective for this kind of task, enhancing a better robustness and an improved performance for the GPI case. Illustrative simulation examples are presented which validate the proposed approach.

  15. The incident of repetitive demands resolution in consumer affairs: empirical analysis of legal feasibility

    Directory of Open Access Journals (Sweden)

    Lucas do Monte Silva

    2017-05-01

    Full Text Available Faced with the scenario of massification of lawsuits, this article intends to analyze the main arguments and questionings of the demands related to moral damage and health plans, on Santa Catarina’s Court of Justice, in order to analyze the possible application of the incident of repetitive demands resolution of the new Civil Procedure Code. To do so, it will be done, first, an analysis of the current context of the Brazilian judiciary, presenting the context of repetitive demands and massification of contracts and introductory aspects of the incident of repetitive demands resolution. Then it will made be a judicial empirical analysis, quantitative and qualitative, through a case study of Santa Catarina Courts of Justice, conducting an empirical study of cross descriptive analysis of the demands related to the issue highlighted above, in order to demonstrate an 'argumentative radiography’ of the judgments of that Court. The results confirmed the possibility of applying IRDR in repetitive demands relating to subjects of this study, with due legal caution, taking into account the high number of “issues of fact” that involve lawsuits that have, among their claims, compensation for moral damages.

  16. Risk of shoulder tendinitis in relation to shoulder loads in monotonous repetitive work

    DEFF Research Database (Denmark)

    Frost, P.; Bonde, J. P.; Mikkelsen, S.

    2002-01-01

    BACKGROUND: Few studies relate the occurrence of shoulder disorders to quantified ergonomic exposures. This study evaluates the hypothesis that shoulder loads in repetitive work might contribute to the occurrence of shoulder tendinitis. METHODS: This is a cross-sectional study of 1961 workers...

  17. Improvement of Polytetrafluoroethylene Surface Energy by Repetitive Pulse Non-Thermal Plasma Treatment in Atmospheric Air

    International Nuclear Information System (INIS)

    Yang Guoqing; Zhang Guanjun; Zhang Wenyuan

    2011-01-01

    Improvement of polytetrafluoroethylene surface energy by non-thermal plasma treatment is presented, using a nanosecond-positive-edge repetitive pulsed dielectric barrier discharge generator in atmospheric air. The electrical parameters including discharging power, peak and density of micro-discharge current were calculated, and the electron energy was estimated. Surface treatment experiments of polytetrafluoroethylene films were conducted for both different applied voltages and different treating durations. Results show that the surface energy of polytetrafluoroethylene film could be improved to 40 mJ/m 2 or more by plasma treatment. Surface roughness measurement and surface X-ray photoelectron spectroscopy analysis indicate that there are chemical etching and implantation of polar oxygen groups in the sample surface treating process, resulting in the improvement of the sample surface energy. Compared with an AC source of 50 Hz, the dielectric barrier discharges generated by a repetitive pulsed source could provide higher peak power, lower mean power, larger micro-discharge current density and higher electron energy. Therefore, with the same applied peak voltage and treating duration, the improvement of polytetrafluoroethylene surface energy using repetitive pulsed plasma is more effective, and the plasma treatment process based on repetitive pulsed dielectric barrier discharges in air is thus feasible and applicable.

  18. Tactile Ranschburg effects: facilitation and inhibitory repetition effects analogous to verbal memory.

    Science.gov (United States)

    Roe, Daisy; Miles, Christopher; Johnson, Andrew J

    2017-07-01

    The present paper examines the effect of within-sequence item repetitions in tactile order memory. Employing an immediate serial recall procedure, participants reconstructed a six-item sequence tapped upon their fingers by moving those fingers in the order of original stimulation. In Experiment 1a, within-sequence repetition of an item separated by two-intervening items resulted in a significant reduction in recall accuracy for that repeated item (i.e., the Ranschburg effect). In Experiment 1b, within-sequence repetition of an adjacent item resulted in significant recall facilitation for that repeated item. These effects mirror those reported for verbal stimuli (e.g., Henson, 1998a . Item repetition in short-term memory: Ranschburg repeated. Journal of Experimental Psychology: Learning, Memory, and Cognition, 24(5), 1162-1181. doi:doi.org/10.1037/0278-7393.24.5.1162). These data are the first to demonstrate the Ranschburg effect with non-verbal stimuli and suggest further cross-modal similarities in order memory.

  19. Topic Repetition in Conversations on Different Days as a Sign of Dementia.

    Science.gov (United States)

    Shinkawa, Kaoru; Yamada, Yasunori

    2018-01-01

    Detecting early signs of dementia in everyday situations becomes more and more important in a rapidly aging society. Language dysfunctions are recognized as the prominent signs of dementia. Previous computational studies characterized these language dysfunctions by using acoustic and linguistic features for detecting dementia. However, they mainly investigated language dysfunctions collected from patients during neuropsychological tests. Language dysfunctions observed during regular conversations in everyday situations received little attention. One of the dysfunctions associated with dementia which is frequently observed in regular conversations is the repetition of a topic on different days. In this study, we propose a feature to characterize topic repetition in conversations on different days. We used conversational data obtained from a daily monitoring service of eight elderly people, two of whom had dementia. Through the analysis of topic extraction with latent Dirichlet allocation, we found that the frequency of topic repetition was significantly higher in people with dementia than in the control group. The results suggest that our proposed feature for identifying topic repetition in regular conversations on different days might be used for detecting dementia.

  20. Learning Correct Responses and Errors in the Hebb Repetition Effect: Two Faces of the Same Coin

    Science.gov (United States)

    Couture, Mathieu; Lafond, Daniel; Tremblay, Sebastien

    2008-01-01

    In a serial recall task, the "Hebb repetition effect" occurs when recall performance improves for a sequence repeated throughout the experimental session. This phenomenon has been replicated many times. Nevertheless, such cumulative learning seldom leads to perfect recall of the whole sequence, and errors persist. Here the authors report…

  1. Solid state pump lasers with high power and high repetition rate

    International Nuclear Information System (INIS)

    Oba, Masaki; Kato, Masaaki; Arisawa, Takashi

    1995-01-01

    We built a laser diode pumped solid state green laser (LDPSSGL) rated at high repetition rate. Two laser heads are placed in one cavity with a rotator in between to design to avoid thermal lensing and thermal birefringence effect. Although average green laser power higher than 10 W was obtained at 1 kHz repetition rate with pulse width of 20-30 nsec, the beam quality was so much deteriorated that energy efficiency was as low as 2 %. Learning from this experience that high power oscillator causes a lot of thermal distortion not only in the laser rod but also in the Q-switch device, we proceeded to built a oscillator/amplifier system. A low power oscillator has a slab type crystal in the cavity. As a result spatial distribution of laser power was extremely improved. As we expect that the high repetition rate solid state laser should be CW operated Q-switch type laser from the view point of lifetime of diode lasers, a conventional arc lamp pumped CW Q-switch green YAG laser of which the repetition rate is changeable from 1 kHz to 5 kHz and the pulse width is 250-570 nsec was also tested to obtain pumping characteristics of a dye laser as a function of power, pulse width etc., and dye laser pulse width of 100-130 nsec were obtained. (author)

  2. Effects of Immediate Repetition in L2 Speaking Tasks: A Focused Study

    Science.gov (United States)

    Bei, Gavin Xiaoyue

    2013-01-01

    This paper reports on a focused investigation into the immediate effects of oral narrative task repetition by two adult EFL learners of intermediate and high proficiency. Two participants performed a narrative speaking task after watching a cartoon video clip and repeated their performance three times, followed by a retrospective report in an…

  3. Accelerated high-frequency repetitive transcranial magnetic stimulation enhances motor activity in rats

    NARCIS (Netherlands)

    El Arfani, Anissa; Parthoens, Joke; Demuyser, Thomas; Servaes, Stijn; De Coninck, Mattias; De Deyn, Peter Paul; Van Dam, Debby; Wyckhuys, Tine; Baeken, Chris; Smolders, Ilse; Staelens, Steven

    2017-01-01

    High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) is currently accepted as an evidence-based treatment option for treatment-resistant depression (TRD). Additionally, HF-rTMS showed beneficial effects on psychomotor retardation in patients. The classical HF-rTMS paradigms however

  4. Repetitive low-frequency stimulation reduces epileptiform synchronization in limbic neuronal networks.

    Science.gov (United States)

    D'Arcangelo, G; Panuccio, G; Tancredi, V; Avoli, M

    2005-01-01

    Deep-brain electrical or transcranial magnetic stimulation may represent a therapeutic tool for controlling seizures in patients presenting with epileptic disorders resistant to antiepileptic drugs. In keeping with this clinical evidence, we have reported that repetitive electrical stimuli delivered at approximately 1 Hz in mouse hippocampus-entorhinal cortex (EC) slices depress the EC ability to generate ictal activity induced by the application of 4-aminopyridine (4AP) or Mg(2+)-free medium (Barbarosie, M., Avoli, M., 1997. CA3-driven hippocampal-entorhinal loop controls rather than sustains in vitro limbic seizures. J. Neurosci. 17, 9308-9314.). Here, we confirmed a similar control mechanism in rat brain slices analyzed with field potential recordings during 4AP (50 microM) treatment. In addition, we used intrinsic optical signal (IOS) recordings to quantify the intensity and spatial characteristics of this inhibitory influence. IOSs reflect the changes in light transmittance throughout the entire extent of the slice, and are thus reliable markers of limbic network epileptiform synchronization. First, we found that in the presence of 4AP, the IOS increases, induced by a train of electrical stimuli (10 Hz for 1 s) or by recurrent, single-shock stimulation delivered at 0.05 Hz in the deep EC layers, are reduced in intensity and area size by low-frequency (1 Hz), repetitive stimulation of the subiculum; these effects were observed in all limbic areas contained in the slice. Second, by testing the effects induced by repetitive subicular stimulation at 0.2-10 Hz, we identified maximal efficacy when repetitive stimuli are delivered at 1 Hz. Finally, we discovered that similar, but slightly less pronounced, inhibitory effects occur when repetitive stimuli at 1 Hz are delivered in the EC, suggesting that the reduction of IOSs seen during repetitive stimulation is pathway dependent as well as activity dependent. Thus, the activation of limbic networks at low frequency

  5. ReRep: Computational detection of repetitive sequences in genome survey sequences (GSS

    Directory of Open Access Journals (Sweden)

    Alves-Ferreira Marcelo

    2008-09-01

    Full Text Available Abstract Background Genome survey sequences (GSS offer a preliminary global view of a genome since, unlike ESTs, they cover coding as well as non-coding DNA and include repetitive regions of the genome. A more precise estimation of the nature, quantity and variability of repetitive sequences very early in a genome sequencing project is of considerable importance, as such data strongly influence the estimation of genome coverage, library quality and progress in scaffold construction. Also, the elimination of repetitive sequences from the initial assembly process is important to avoid errors and unnecessary complexity. Repetitive sequences are also of interest in a variety of other studies, for instance as molecular markers. Results We designed and implemented a straightforward pipeline called ReRep, which combines bioinformatics tools for identifying repetitive structures in a GSS dataset. In a case study, we first applied the pipeline to a set of 970 GSSs, sequenced in our laboratory from the human pathogen Leishmania braziliensis, the causative agent of leishmaniosis, an important public health problem in Brazil. We also verified the applicability of ReRep to new sequencing technologies using a set of 454-reads of an Escheria coli. The behaviour of several parameters in the algorithm is evaluated and suggestions are made for tuning of the analysis. Conclusion The ReRep approach for identification of repetitive elements in GSS datasets proved to be straightforward and efficient. Several potential repetitive sequences were found in a L. braziliensis GSS dataset generated in our laboratory, and further validated by the analysis of a more complete genomic dataset from the EMBL and Sanger Centre databases. ReRep also identified most of the E. coli K12 repeats prior to assembly in an example dataset obtained by automated sequencing using 454 technology. The parameters controlling the algorithm behaved consistently and may be tuned to the properties

  6. Generating Units

    Data.gov (United States)

    Department of Homeland Security — Generating Units are any combination of physically connected generators, reactors, boilers, combustion turbines, and other prime movers operated together to produce...

  7. The Effect of Task Instructions on Students' Use of Repetition in Argumentative Discourse

    Science.gov (United States)

    Gilabert, Sandra; Garcia-Mila, Merce; Felton, Mark K.

    2013-11-01

    The reasoning belief of argumentum ad nauseam assumes that when someone repeats something often enough, he or she becomes more convincing. The present paper analyses the use of this strategy by seventh-grade students in an argumentation task. Sixty-five students (mean age: 12.2, SD = 0.4) from a public school in a mid-sized urban environment took part in the study. The students were asked to either argue to convince an opposing partner or argue to reach consensus with an opposing partner on three dilemmas that dealt with energy sources. Data were gathered according to a between-groups design that included one independent variable (argumentative goal: to convince vs. to reach consensus) and one dependent variable (the degree of argumentative repetitions). We predicted that in the condition to convince their partner, the students would use the repetition strategy more often in their attempts to be persuasive. Our findings show that the mean number of argumentative repetitions was significantly higher for the persuasion group for both of the most frequent argumentative structures (claim and claim data). The mean percentage of repeated claims for the persuasion condition was 86.2 vs. 69.0 for the consensus condition. For the claim data, the mean percentage for the persuasion group was 35.2 vs. 24.3 for the consensus group. Also, students in the persuasion group tended to repeat one idea many times rather than repeating many ideas a few times within the same argumentative structure. The results of our study support the hypothesis that the goal of the argumentative task mediates argumentative discourse and, more concretely, the rate of repetitions and the conceptual diversity of the statements. These differences in rates of repetition and conceptual diversity are related to the amount of learning produced by the instructional goal. We apply Mercer's idea that not all classroom argumentation tasks promote learning equally.

  8. Semantic priming, not repetition priming, is to blame for false hearing.

    Science.gov (United States)

    Rogers, Chad S

    2017-08-01

    Contextual and sensory information are combined in speech perception. Conflict between the two can lead to false hearing, defined as a high-confidence misidentification of a spoken word. Rogers, Jacoby, and Sommers (Psychology and Aging, 27(1), 33-45, 2012) found that older adults are more susceptible to false hearing than are young adults, using a combination of semantic priming and repetition priming to create context. In this study, the type of context (repetition vs. sematic priming) responsible for false hearing was examined. Older and young adult participants read and listened to a list of paired associates (e.g., ROW-BOAT) and were told to remember the pairs for a later memory test. Following the memory test, participants identified words masked in noise that were preceded by a cue word in the clear. Targets were semantically associated to the cue (e.g., ROW-BOAT), unrelated to the cue (e.g., JAW-PASS), or phonologically related to a semantic associate of the cue (e.g., ROW-GOAT). How often each cue word and its paired associate were presented prior to the memory test was manipulated (0, 3, or 5 times) to test effects of repetition priming. Results showed repetitions had no effect on rates of context-based listening or false hearing. However, repetition did significantly increase sensory information as a basis for metacognitive judgments in young and older adults. This pattern suggests that semantic priming dominates as the basis for false hearing and highlights context and sensory information operating as qualitatively different bases for listening and metacognition.

  9. A long-pulse repetitive operation magnetically insulated transmission line oscillator

    International Nuclear Information System (INIS)

    Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang

    2014-01-01

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO

  10. A long-pulse repetitive operation magnetically insulated transmission line oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang [College of Optoelectric Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2014-05-15

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO.

  11. A long-pulse repetitive operation magnetically insulated transmission line oscillator.

    Science.gov (United States)

    Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang

    2014-05-01

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO.

  12. 5HT2A receptor blockade in dorsomedial striatum reduces repetitive behaviors in BTBR mice.

    Science.gov (United States)

    Amodeo, D A; Rivera, E; Cook, E H; Sweeney, J A; Ragozzino, M E

    2017-03-01

    Restricted and repetitive behaviors are a defining feature of autism, which can be expressed as a cognitive flexibility deficit or stereotyped, motor behaviors. There is limited knowledge about the underlying neuropathophysiology contributing to these behaviors. Previous findings suggest that central 5HT 2A receptor activity is altered in autism, while recent work indicates that systemic 5HT 2A receptor antagonist treatment reduces repetitive behaviors in an idiopathic model of autism. 5HT 2A receptors are expressed in the orbitofrontal cortex and striatum. These two regions have been shown to be altered in autism. The present study investigated whether 5HT 2A receptor blockade in the dorsomedial striatum or orbitofrontal cortex in the BTBR mouse strain, an idiopathic model of autism, affects the phenotype related to restricted and repetitive behaviors. Microinfusion of the 5HT 2A receptor antagonist, M100907 into the dorsomedial striatum alleviated a reversal learning impairment and attenuated grooming behavior. M100907 infusion into the orbitofrontal cortex increased perseveration during reversal learning and potentiated grooming. These findings suggest that increased 5HT 2A receptor activity in the dorsomedial striatum may contribute to behavioral inflexibility and stereotyped behaviors in the BTBR mouse. 5HT 2A receptor signaling in the orbitofrontal cortex may be critical for inhibiting a previously learned response during reversal learning and expression of stereotyped behavior. The present results suggest which brain areas exhibit abnormalities underlying repetitive behaviors in an idiopathic mouse model of autism, as well as which brain areas systemic treatment with M100907 may principally act on in BTBR mice to attenuate repetitive behaviors. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  13. Repetition Performance And Blood Lactate Responses Adopting Different Recovery Periods Between Training Sessions In Trained Men.

    Science.gov (United States)

    Miranda, Humberto; de Freitas Maia, Marianna; Paz, Gabriel Andrade; de Souza, João A A A; Simão, Roberto; de Araújo Farias, Déborah; Willardson, Jeffrey M

    2017-02-08

    The purpose of this study was to examine the effect of different recovery periods (24h, 48h, and 72h) between repeated resistance training (RT) sessions for the upper body muscles on repetition performance and blood lactate responses in trained men. Sixteen recreationally trained men (age: 26.1 ± 3.1 years; height: 179 ± 4.5 cm; body mass: 82.6 ± 4.0 kg, 4.5 ± 2.2 years of RT experience) participated in this study. Eight-repetition maximum (8-RM) loads were determined for the bench press (BP), 30° incline bench press (BP30), and 45° incline bench press (BP45) exercises. To assess the effects of different recovery periods between repeated training sessions, three protocols were performed in randomized order, including: 24 hours (P24); 48 hours (P48); and 72 hours (P72). Each RT session consisted of performing four repetition maximum sets of BP, BP30, and BP45 with 8-RM loads and 2-minute rest intervals between sets. Blood lactate levels were measured pre-session (PRE), immediately post-session (POST), 3 minutes post-session (P3), and 5 minutes post-session (P5). For the P24 protocol, significant decreases in repetition performance were found between sessions for the BP, BP30, and BP45 exercises, respectively. When considering session 2 only, the total work (repetition x sets) was significantly higher in P48 and P72 versus P24 for the BP30 and BP45 exercises. Blood lactate levels (i.e. POST, P3, and P5) significantly increased for session 2 under the P24 compared to the P48 and P72 protocols, respectively. Therefore, coaches and practitioners who need to accomplish a higher training volume for the upper body muscles should adopt recovery periods longer than 24 hours between sessions that train the same or similar muscle groups.

  14. Comprehension priming as rational expectation for repetition: Evidence from syntactic processing.

    Science.gov (United States)

    Myslín, Mark; Levy, Roger

    2016-02-01

    Why do comprehenders process repeated stimuli more rapidly than novel stimuli? We consider an adaptive explanation for why such facilitation may be beneficial: priming is a consequence of expectation for repetition due to rational adaptation to the environment. If occurrences of a stimulus cluster in time, given one occurrence it is rational to expect a second occurrence closely following. Leveraging such knowledge may be particularly useful in online processing of language, where pervasive clustering may help comprehenders negotiate the considerable challenge of continual expectation update at multiple levels of linguistic structure and environmental variability. We test this account in the domain of structural priming in syntax, making use of the sentential complement-direct object (SC-DO) ambiguity. We first show that sentences containing SC continuations cluster in natural language, motivating an expectation for repetition of this structure. Second, we show that comprehenders are indeed sensitive to the syntactic clustering properties of their current environment. In a series of between-groups self-paced reading studies, we find that participants who are exposed to clusters of SC sentences subsequently process repetitions of SC structure more rapidly than participants who are exposed to the same number of SCs spaced in time, and attribute the difference to the learned degree of expectation for repetition. We model this behavior through Bayesian belief update, showing that (the optimal degree of) sensitivity to clustering properties of syntactic structures is indeed learnable through experience. Comprehension priming effects are thus consistent with rational expectation for repetition based on adaptation to the linguistic environment. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Probing background ionization: positive streamers with varying pulse repetition rate and with a radioactive admixture

    International Nuclear Information System (INIS)

    Nijdam, S; Van Veldhuizen, E M; Ebert, U; Wormeester, G

    2011-01-01

    Positive streamers need a source of free electrons ahead of them to propagate. A streamer can supply these electrons by itself through photo-ionization, or the electrons can be present due to external background ionization. Here we investigate the effects of background ionization on streamer propagation and morphology by changing the gas composition and the repetition rate of the voltage pulses, and by adding a small amount of radioactive 85 Kr. We find that the general morphology of a positive streamer discharge in high-purity nitrogen depends on background ionization: at lower background ionization levels the streamers branch more and have a more feather-like appearance. This is observed both when varying the repetition rate and when adding 85 Kr, though side branches are longer with the radioactive admixture. But velocities and minimal diameters of streamers are virtually independent of the background ionization level. In air, the inception cloud breaks up into streamers at a smaller radius when the repetition rate and therefore the background ionization level is higher. When measuring the effects of the pulse repetition rate and of the radioactive admixture on the discharge morphology, we found that our estimates of background ionization levels are consistent with these observations; this gives confidence in the estimates. Streamer channels generally do not follow the paths of previous discharge channels for repetition rates of up to 10 Hz. We estimate the effect of recombination and diffusion of ions and free electrons from the previous discharge and conclude that the old trail has largely disappeared at the moment of the next voltage pulse; therefore the next streamers indeed cannot follow the old trail.

  16. Meaningful Words and Non-Words Repetitive Articulatory Rate (Oral Diadochokinesis) in Persian Speaking Children.

    Science.gov (United States)

    Zamani, Peyman; Rezai, Hossein; Garmatani, Neda Tahmasebi

    2017-08-01

    Repetitive articulatory rate or Oral Diadochokinesis (oral-DDK) shows a guideline for appraisal and diagnosis of subjects with oral-motor disorder. Traditionally, meaningless words repetition has been utilized in this task and preschool children have challenges with them. Therefore, we aimed to determine some meaningful words in order to test oral-DDK in Persian speaking preschool children. Participants were 142 normally developing children, (age range 4-6 years), who were asked to produce /motæka, golabi/ as two meaningful Persian words and /pa-ta-ka/ as non-word in conventional oral-DDK task. We compared the time taken for 10-times fast repetitions of two meaningful Persian words and the tri-syllabic nonsense word /pa-ta-ka/. Praat software was used to calculate the average time that subjects took to produce the target items. In 4-5 year old children, [Formula: see text] of time taken for 10-times repetitions of /pa-ta-ka, motæka, golabi/ were [Formula: see text], and [Formula: see text] seconds respectively, and in 5-6 year old children were [Formula: see text], and [Formula: see text] seconds respectively. Findings showed that the main effect of type of words on oral diadochokinesis was significant ([Formula: see text]). Children repeated meaningful words /motæka, golabi/ faster than the non-word /pa-ta-ka/. Sex and age factors had no effect on time taken for repetition of oral-DDK test. It is suggested that Speech Therapists can use meaningful words to facilitate oral-DDK test for children.

  17. Counting repetitions: an observational study of video game play in people with chronic poststroke hemiparesis.

    Science.gov (United States)

    Peters, Denise M; McPherson, Aaron K; Fletcher, Blake; McClenaghan, Bruce A; Fritz, Stacy L

    2013-09-01

    The use of video gaming as a therapeutic intervention has increased in popularity; however, the number of repetitions in comparison with traditional therapy methods has yet to be investigated. The primary purpose of this study was to document and compare the number of repetitions performed while playing 1 of 2 video gaming systems for a time frame similar to that of a traditional therapy session in individuals with chronic stroke. Twelve participants with chronic stroke (mean age, 66.8 ± 8.2 years; time poststroke, 19.2 ± 15.4 months) completed video game play sessions, using either the Nintendo Wii or the Playstation 2 EyeToy. A total of 203 sessions were captured on video record; of these, 50 sessions for each gaming system were randomly selected for analysis. For each selected record, active upper and lower extremity repetitions were counted for a 36-minute segment of the recorded session. The Playstation 2 EyeToy group produced an average of 302.5 (228.1) upper extremity active movements and 189.3 (98.3) weight shifts, significantly higher than the Nintendo Wii group, which produced an average of 61.9 (65.7) upper extremity active movements and 109.7 (78.5) weight shifts. No significant differences were found in steps and other lower extremity active movements between the 2 systems. The Playstation 2 EyeToy group produced more upper extremity active movements and weight shifting movements than the Nintendo Wii group; the number and type of repetitions varied across games. Active gaming (specifically Playstation 2 EyeToy) provided more upper extremity repetitions than those reported in the literature by using traditional therapy, suggesting that it may be a modality to promote increased active movements in individuals poststroke.

  18. Change in power output across a high-repetition set of bench throws and jump squats in highly trained athletes.

    Science.gov (United States)

    Baker, Daniel G; Newton, Robert U

    2007-11-01

    Athletes experienced in maximal-power and power-endurance training performed 1 set of 2 common power training exercises in an effort to determine the effects of moderately high repetitions upon power output levels throughout the set. Twenty-four and 15 athletes, respectively, performed a set of 10 repetitions in both the bench throw (BT P60) and jump squat exercise (JS P60) with a resistance of 60 kg. For both exercises, power output was highest on either the second (JS P60) or the third repetition (BT P60) and was then maintained until the fifth repetition. Significant declines in power output occurred from the sixth repetition onwards until the 10th repetition (11.2% for BT P60 and 5% for JS P60 by the 10th repetition). These findings suggest that athletes attempting to increase maximal power limit their repetitions to 2 to 5 when using resistances of 35 to 45% 1RM in these exercises.

  19. Effects of picosecond laser repetition rate on ablation of Cr12MoV cold work mold steel

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Baoye; Deng, Leimin; Liu, Peng; Zhang, Fei; Duan, Jun, E-mail: duans@hust.edu.cn; Zeng, Xiaoyan

    2017-07-01

    In this paper, the effects of pulse repetition rate on ablation efficiency and quality of Cr12MoV cold work mold steel have been studied using a picosecond (ps) pulse Nd:YVO{sub 4} laser system at λ= 1064 nm. The experimental results of area ablation on target surface reveal that laser repetition rate plays a significant role in controlling ablation efficiency and quality. Increasing the laser repetition rate, while keeping a constant mean power improves the ablation efficiency and quality. For each laser mean power, there is an optimal repetition rate to achieve a higher laser ablation efficiency with low surface roughness. A high ablation efficiency of 42.29, 44.11 and 47.52 μm{sup 3}/mJ, with surface roughness of 0.476, 0.463 and 0.706 μm could be achieved at laser repetition rate of 10 MHz, for laser mean power of 15, 17 and 19 W, respectively. Scanning electron microcopy images revels that the surface morphology evolves from rough with numerous craters, to flat without pores when we increased the laser repetition rate. The effects of laser repetition rate on the heat accumulation, plasma shield and ablation threshold were analyzed by numerical simulation, spectral analysis and multi-laser shot, respectively. The synergetic effects of laser repetition rate on laser ablation rate and machining quality were analyzed and discussed systemically in this paper.

  20. The Role of Reminding in the Effects of Spaced Repetitions on Cued Recall: Sufficient but Not Necessary

    Science.gov (United States)

    Wahlheim, Christopher N.; Maddox, Geoffrey B.; Jacoby, Larry L.

    2014-01-01

    Three experiments examined the role of study-phase retrieval (reminding) in the effects of spaced repetitions on cued recall. Remindings were brought under task control to evaluate their effects. Participants studied 2 lists of word pairs containing 3 item types: single items that appeared once in List 2, within-list repetitions that appeared…