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Conservation of the 5S-bearing chromosome pair and co-localization with major rDNA clusters in five species of Astyanax (Pisces, Characidae)

Almeida-Toledo, L. F.; Ozouf-Costaz, C.; Foresti, F.; Bonillo, C.; Porto-Foresti, F.; Daniel-Silva, MFZ
Fonte: Karger Publicador: Karger
Tipo: Artigo de Revista Científica Formato: 229-233
ENG
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Major and 5S ribosomal genes have been localized in chromosomes from five fish species, genus Aslyanax, using in situ hybridization (FISH) with 28S and 5S rDNA probes. In situ signals for the major rDNA co-localized with the 5S rDNA clusters in the pericentromeric region of one marker chromosome in all five species analyzed. The conserved localization of these two rDNA clusters in the five related Astyanax species was considered as indicative of a close relationship among them. The use of these molecular markers for elucidating evolutionary relationships among closely related taxa is discussed. Copyright (C) 2002 S. Karger AG, Basel.

Genetic identification of the sharks Rhizoprionodon porosus and R. lalandii by PCR-RFLP and nucleotide sequence analyses of 5S rDNA

Pinhal, Danillo; Gadig, Otto Bismarck Fazzano; Martins, Cesar
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 35-38
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); A molecular approach based on nuclear 5S rDNA sequence variability was applied successfully to correctly identify samples from the two Rhizoprionodon species collected in the wild or sold in markets. The sequence of the non-transcribed spacer (NTS) of the 5S rDNA showed high interspecific variability and no intra-specific polymorphism, making it a useful marker for sharpnose shark identification. Polymorphisms in the NTS sequences of Rhizoprionodon sharks also created unique restriction patterns for each species after PCR-RFLP analysis. The 5S rDNA polymorphism represents a fast and non expensive tool to access species identification when rapid and unequivocal identification of shark products is needed, particularly for future management and other investigations.

Chromosomal Variability among Allopatric Populations of Erythrinidae Fish Hoplias malabaricus: Mapping of Three Classes of Repetitive DNAs

Cioffi, M. B.; Martins, C.; Centofante, L.; Jacobina, U.; Bertollo, L. A. C.
Fonte: Karger Publicador: Karger
Tipo: Artigo de Revista Científica Formato: 132-141
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 07/05565-5; Karyotype and chromosomal characteristics from 3 allopatric populations of Hoplias malabaricus, cytogenetically the most studied Erythrinidae taxon, were investigated using different staining techniques (C-, Ag-, and CMA(3) banding) as well as fluorescent in situ hybridization (FISH) to detect 18S rDNA, 5S rDNA, and 5SHindIII satellite DNA sites. The isolation, cloning and characterization of an 18S rDNA probe from H. malabaricus genome were also performed for the first time in order to develop a more specific probe. The 3 populations, named PR, CR, and DR, showed identical karyotypes, with 2n = 42 chromosomes composed of 11 m pairs and 10 sm pairs, without heteromorphic sex chromosomes, which characterize the populations as belonging to karyomorph A. In all populations C-positive heterochromatin was situated in the centromeric/pericentromeric regions of the chromosomes, as well as in the telomeric region of several pairs. A conspicuous proximal heterochromatic block on the long arm of pair No. 16 was the only GC-rich segment in the karyotypes. 5SHindIII satellite DNA was always mapped in the centromeric region of several chromosomes. The 18S rDNA sites were situated on the telomeric or centromeric regions...

Chromosomal organization of the 18S and 5S rRNAs and histone H3 genes in Scarabaeinae coleopterans: insights into the evolutionary dynamics of multigene families and heterochromatin

Cabral-de-Mello, Diogo Cavalcanti; Oliveira, Sarah G.; de Moura, Rita C.; Martins, Cesar
Fonte: Biomed Central Ltd. Publicador: Biomed Central Ltd.
Tipo: Artigo de Revista Científica Formato: 12
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Background: Scarabaeinae beetles show a high level of macro-chromosomal variability, although the karyotypic organization of heterochromatin and multigene families (rDNAs and histone genes) is poorly understood in this group. To better understand the chromosomal organization and evolution in this group, we analyzed the karyotypes, heterochromatin distribution and chromosomal locations of the rRNAs and histone H3 genes in beetles belonging to eight tribes from the Scarabaeinae subfamily (Coleoptera, Scarabaeidae).Results: The number of 18S rRNA gene (a member of the 45S rDNA unit) sites varied from one to 16 and were located on the autosomes, sex chromosomes or both, although two clusters were most common. Comparison of the 45S rDNA cluster number and the diploid numbers revealed a low correlation value. However, a comparison between the number of 45S rDNA sites per genome and the quantity of heterochromatin revealed (i) species presenting heterochromatin restricted to the centromeric/pericentromeric region that contained few rDNA sites and (ii) species with a high quantity of heterochromatin and a higher number of rDNA sites. In contrast to the high variability for heterochromatin and 45S rDNA cluster...

Distribution of 45S and 5S rDNA sites in 23 species of Eleocharis (Cyperaceae)

Maximiano da Silva, Carlos Roberto; Quintas, Carolina Cristina; Laforga Vanzela, Andre Luis
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 951-957
ENG
Relevância na Pesquisa
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Studies of rDNA location in holocentric chromosomes of the Cyperaceae are scarce, but a few reports have indicated the occurrence of multiple 45S rDNA sites at terminal positions, and in the decondensed state of these regions in prometaphase/metaphase. To extend our knowledge of the number 45S and 5S rDNA sites and distribution in holocentric chromosomes of the Cyperaceae, 23 Brazilian species of Eleocharis were studied. FISH showed 45S rDNA signals always located in terminal regions, which varied from two (E. bonariensis with 2n = 20) to ten (E. flavescens with 2n = 10 and E. laeviglumis with 2n = 60). 5S rDNA showed less variation, with 16 species exhibiting two sites and 7 species four sites, preferentially at terminal positions, except for four species (E. subarticulata, E. flavescens, E. sellowiana and E. geniculata) that showed interstitial sites. The results are discussed in order to understand the predominance of terminal rDNA sites, the mechanisms involved in the interstitial positioning of 5S rDNA sites in some species, and the events of amplification and dispersion of 45S rDNA terminal sites.

Cytogenetic analysis in three Bryconamericus species (Characiformes, Characidae): first description of the 5S rDNA-bearing chromosome pairs in the genus

Piscor, Diovani; Ribacinko-Piscor, Daniela Bocagini; Fernandes, Carlos Alexandre; Parise-Maltempi, Patricia Pasquali
Fonte: Biomed Central Ltd. Publicador: Biomed Central Ltd.
Tipo: Artigo de Revista Científica Formato: 8
ENG
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Background: Nowadays, the genus Bryconamericus is placed in subfamily Stevardiinae within of Characidae, but not shows consistent evidence of monophyletism. The purpose of this work was to study the chromosomes of three species of Bryconamericus, aiming to add cytogenetic knowledge and contribute to the understanding of the chromosomal evolution of this genus.Results: The chromosomes of three species of Bryconamericus were analyzed using cytogenetic techniques. The karyotype of Bryconamericus stramineus contained 6 metacentric (m) + 10 submetacentric (sm) + 16 subtelocentric (st) + 20 acrocentric (a), the fundamental number (FN) of 84, one silver impregnated (Ag-NOR) pair, one pair bearing the 18S ribosomal DNA sites, another pair bearing the 5S rDNA sites, and a few positive C-bands. Bryconamericus turiuba had a karyotype containing 8 m + 10sm + 14st + 20a (FN = 84), one chromosome pair Ag-NOR, two pairs bearing the 18S rDNA sites, two pairs bearing the 5S rDNA sites, and a few C-band regions. Bryconamericus cf. iheringii had a karyotype containing 10 m + 14sm + 18st + 10a (FN = 94), including one pair with a secondary constriction Ag-NOR positive. In this karyotype the fluorescent in situ hybridization (FISH) showed the 18S and 5S rDNA probe in adjacent position.Conclusions: The results obtained in this work showed different characteristics in the organization of two multigene families...

Patterns of rDNA and telomeric sequences diversification: contribution to repetitive DNA organization in Phyllostomidae bats

Calixto, Merilane da Silva; Andrade, Izaquiel Santos de; Cabral-de-Mello, Diogo Cavalcanti; Santos, Neide; Martins, Cesar; Loreto, Vilma; Souza, Maria Jose de
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 49-58
ENG
Relevância na Pesquisa
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Chromosomal organization and the evolution of genome architecture can be investigated by physical mapping of the genes for 45S and 5S ribosomal DNAs (rDNAs) and by the analysis of telomeric sequences. We studied 12 species of bats belonging to four subfamilies of the family Phyllostomidae in order to correlate patterns of distribution of heterochromatin and the multigene families for rDNA. The number of clusters for 45S gene ranged from one to three pairs, with exclusively location in autosomes, except for Carollia perspicillata that had in X chromosome. The 5S gene all the species studied had only one site located on an autosomal pair. In no species the 45S and 5S genes collocated. The fluorescence in situ hybridization (FISH) probe for telomeric sequences revealed fluorescence on all telomeres in all species, except in Carollia perspicillata. Non-telomeric sites in the pericentromeric region of the chromosomes were observed in most species, ranged from one to 12 pairs. Most interstitial telomeric sequences were coincident with heterochromatic regions. The results obtained in the present work indicate that different evolutionary mechanisms are acting in Phyllostomidae genome architecture...

Uma metodologia de 5S para o setor de serviços

Silva, Dalmir Augusto da
Fonte: Florianópolis, SC Publicador: Florianópolis, SC
Tipo: Dissertação de Mestrado Formato: [200] f.| il. +
POR
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.; Os últimos anos marcaram um grande aumento no nível de concorrência no setor bancário brasileiro. Neste novo cenário os bancos brasileiros devem buscar ações que possibilitem a manutenção de seu potencial competitivo. Neste trabalho é analisado uma ação desenvolvida no BESC - Banco do Estado de Santa Catarina: o 5S-BESC, e discutidos os motivos que levaram ao desenvolvimento do 5S-BESC, dentre estes, a necessidade de promover uma mudança cultural. Posteriormente é apresentado o 5S-BESC, ressaltando-se uma de suas características mais importantes: a ação em grupo com foco em resultados promovendo a mudança cultural. Finalmente são apresentados os resultados da aplicação e discutidos conceitos associados ao seu desenvolvimento e aplicação.

Lean and quality management integration: improvement program implementation in a service company

Leitão, Diogo; Pereira, Teresa; Sampaio, Paulo
Fonte: IBS Publicador: IBS
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
Relevância na Pesquisa
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Lean Thinking is an important pillar in the success of any program of continuous improvement process. Its tools are useful means in the analysis, control and organization of important data for correct decision making in organizations. This project had as main objective the design of a program of quality improvement in Eurico Ferreira, S.A., based on the evaluation of customer satisfaction and the implementation of 5S. Subsequently, we have selected which business area of the company to address. After the selection, there was an initial diagnostic procedure, identifying the various points of improvement to which some tools of Lean Thinking have been applied, in particular Value Stream Mapping and 5S methodology. With the first, we were able to map the current state of the process in which all stakeholders were represented as well as the flow of materials and information throughout the process. The 5S methodology allowed to act on the wastage, identifying and implementing various process improvements.

A split binding site for TFIIIC on the Xenopus 5S gene.

Majowski, K; Mentzel, H; Pieler, T
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1987 EN
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We have previously shown that of the two functional domains which constitute the Xenopus 5S gene promoter the common, conserved box A element is directly involved in the binding of the common transcription factor IIIC. Here, we describe the investigation of the role of the 5S gene specific promoter element, box C, in transcription factor binding. Analysis of 22 different single site basepair changes reveals that mutations created within the 5'-region of this segment interfere with transcription due to a reduced affinity for TFIIIA, whereas sequence alterations introduced into the 3'-region of the same element similarly inhibit transcription, but do not result in a measurable defect in TFIIIA binding. Instead, they clearly reduce the affinity for TFIIIC. DNase I protection experiments with TFIIIA on 5S mutants which have an increased spacing of box A and box C demonstrate that TFIIIA recognizes a specific box A sequence element and that the factor has to be properly aligned on the DNA template in order to allow stable complex formation with TFIIIC to proceed. The structural and functional organization of protein binding signals on the 5S gene internal control region will be discussed in regard to these results.

Structural features of Bacillus precursor 5S RNA involved in the interaction with RNAase M5.

Stiekema, W J; Raué, H A; Duin, M M; Planta, R J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 25/11/1980 EN
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Mature 5S (m5S) RNA from Bacillus licheniformis specifically and almost completely inhibits in vitro maturation of bacillus precursor 5S (p5S) RNA, showing that the maturation enzyme RNAase M5 can recognize Bacillus m5S RNA. E. coli m5S RNA is a much less efficient inhibitor, whereas S. carlsbergensis 5S RNA inhibits maturation by about 70%. The differences in inhibition can be correlated with the position of the sequence UAGG (residues 101-104 in B. licheniformis m5S RNA) relative to the double-helical region formed by the 5'- and 3'-terminal sequences (molecular stalk) of m5S RNA. Recent experiments by Meyhack and Pace (Biochemistry 17 (1980) 5804-5810) demonstrated this UAGG sequence to be indispensable for processing of p5S RNA. Other elements of secondary and/or tertiary structure are also required, however. The effect of artificially constructed "5S RNA" molecules having defined disturbances in the base-pairing within the molecular stalk on in vitro maturation shows that base-pairing in the immediate neighbourhood of the bonds to be cleaved during maturation is crucial to recognition of p5S RNA by RNAase M5. G.U pairs are tolerated in this region, however, without loss of efficiency in maturation. Base-pairing does not have to extend throughout the complete molecular stalk. The introduction of an A/C combination at the end of the molecular stalk removed from the bonds cleaved by RNAase M5 does not significantly impair the efficiency of maturation.

Specific transcription of an Acanthamoeba castellanii 5S RNA gene in homologous nuclear extracts.

Zwick, M G; Imboden, M A; Paule, M R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 11/04/1991 EN
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An RNA polymerase III in vitro transcription system has been developed from the protist Acanthamoeba castellanii. The system is dependent on a cloned 5S RNA gene and utilizes a nuclear extract which contains all the necessary protein components. The system is assembled from completely homologous components. Primer extension and RNA sequencing analysis confirm that the in vitro 5S RNA transcript is identical to the 5S RNA isolated from cells. The transcription complex forms unusually rapidly on the 5S RNA gene and is stable to challenge by excess competitor templates. Several 5' deletion mutants were constructed and indicate that the region upstream of -33 is dispensable. Deletion to +16 show the region between -33 and +16 to be required for transcription, a region outside the canonical internal control region.

Yeast TFIIIA + TFIIIC/tau-factor, but not yeast TFIIIA alone, interacts with the Xenopus 5S rRNA gene.

Struksnes, K; Forus, A; Gabrielsen, O S; Oyen, T B
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 11/02/1991 EN
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The successful use of mixed heterologous in vitro transcription systems has suggested that the species specificity of RNA polymerase III transcription is low. To see if this extends to lower eukaryotic class III transcription factors, we compared the interactions of the two yeast assembly factors, TFIIIA and TFIIIC/tau factor, with a homologous yeast 5S rRNA gene and a heterologous Xenopus laevis somatic 5S rRNA gene. Transcription assays showed that the Xenopus gene was transcriptionally inactive in a crude cell-free yeast extract that actively transcribes the homologous gene. However, the Xenopus gene was still able to compete for limiting transcription factors. Electrophoretic DNA binding assays revealed that while TFIIIA bound avidly to the yeast gene (generating the 'A-complex'), it had no affinity for the Xenopus 5S rRNA gene. Nevertheless, a complex of both TFIIIA and TFIIIC/tau factor (the 'AC-complex') was formed on the two genes with similar affinity, although only the complex assembled on the homologous gene was able to activate transcription. Thus enough sequence information is present on the heterologous gene to direct transcription factor assembly, but not to activate transcription. Like its counterpart in Xenopus, the yeast TFIIIA appears to be a zinc binding protein that is inactivated by EDTA and 1...

Estudios citogenéticos en especies de Passiflora subgénero Passiflora (Passifloraceae); Cytogenetic studies in species of Passiflora subgenus Passiflora (Passifloraceae)

Chiapero, Ana Laura; Las Peñas, Maria Laura; Amela Garcia, Maria Teresa; Bernardello, Gabriel Luis Mario
Fonte: Sociedad Argentina de Botánica Publicador: Sociedad Argentina de Botánica
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
SPA
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Passiflora comprende alrededor de 525 especies con x = 9 ó 6. Se realizó un estudio citogenético de cuatro especies del subgénero Passiflora que crecen en la Argentina. Se utilizaron las técnicas de Giemsa, bandeo cromosómico fluorescente CMA/DAPI y FISH (sonda 18-5,8-26S y 5S) en cromosomas mitóticos. P. caerulea, P. tucumanensis y P. cincinnata resultaron diploides (2n = 18) mientras que P. mooreana, tetraploide (2n=36). Los cariotipos fueron altamente simétricos con la fórmula 8 m + 1 sm, duplicada en P. mooreana. Con CMA/DAPI, todos los diploides presentaron dos o tres pares de bandas terminales CMA+ /DAPI- , mientras que la especie tetraploide presentó cinco pares, asociadas a NOR. Con FISH, los loci 18-5,8-26S coincidieron en número y posición con las bandas CMA+ /DAPI- . En cada especie, el número de sitios para los genes de 5S ADNr concordaron con el nivel de ploidía. Los datos de P. tucumanensis y P. mooreana se reportan por primera vez, siendo esta última el primer tetraploide conocido para el subgénero Passiflora. Los patrones de FISH y las bandas heterocrómaticas variaron entre las especies de Passiflora estudiadas, principalmente en el número y distribución de las señales.; Cytogenetic studies in species of Passiflora subgenus Passiflora (Passifloraceae). Passiflora has nearly 525 spp. with x = 9 or 6. A cytogenetic study of four species from subgenus Passiflora that
grow in Argentina was performed. Giemsa technique...

Implementação de ferramentas Lean na Empresa de Cervejas da Madeira

Freitas, Filipa Alexandra Alves de
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Dissertação de Mestrado
POR
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A crescente competitividade do mercado e o aumento das exigências dos clientes no que diz respeito a baixos custos, diminuição dos tempos de entrega e aumento da qualidade influenciam a produtividade das empresas. Deste modo, as empresas tentam encontrar novos métodos que permitam aumentar a capacidade produtiva, diminuir os desperdícios e responder mais rapidamente às necessidades dos consumidores. Neste contexto surge o projeto desenvolvido na ECM no âmbito do Mestrado em Engenharia e Gestão Industrial. Este projeto teve por objetivos a implementação de ferramentas Lean Thinking que permitissem diminuir os desperdícios, reduzir os tempos improdutivos e organizar os postos de trabalho. O trabalho normalizado permitiu identificar as etapas que não acrescentavam valor ao produto, analisar os métodos de trabalho dos operadores e definir propostas de melhoria que aumentassem a produtividade das linhas de enchimento e a qualidade do produto. O SMED permitiu reduzir os erros de setup, aumentar a produtividade das máquinas e reduzir o tempo necessário para realizar a mudança de material da sopradora em 18,25 minutos, da engradadora em 0,98 minutos e da rotuladora em 26,93 minutos. O 5S permitiu organizar e limpar os postos de trabalho da rotuladora e da engradadora...

Peak shifts due to $B^{(*)}-\bar{B}^{(*)}$ rescattering in $\Upsilon(5S)$ dipion transitions

Meng, Ce; Chao, Kuang-Ta
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We study the energy distributions of dipion transitions $\Upsilon(5S)$ to $\Upsilon(1S,2S,3S)\pi^+\pi^-$ in the final state rescattering model. Since the $\Upsilon(5S)$ is well above the open bottom thresholds, the dipion transitions are expected to mainly proceed through the real processes $\Upsilon(5S)\to B^{(*)}\bar{B}^{(*)}$ and $B^{(*)}\bar{B}^{(*)}\to \Upsilon(1S,2S,3S)\pi^+\pi^-$. We find that the energy distributions of $\Upsilon(1S,2S,3S)\pi^+\pi^-$ markedly differ from that of $\Upsilon(5S)\to B^{(*)}\bar{B}^{(*)}$. In particular, the resonance peak will be pushed up by about 7-20 MeV for these dipion transitions relative to the main hadronic decay modes. These predictions can be used to test the final state rescattering mechanism in hadronic transitions for heavy quarkonia above the open flavor thresholds.; Comment: Version published in PRD, energy dependence of the total width in Eq.(12) restored and corresponding figure changed, more discussion and clarification added

Observation of anomalous Upsilon(1S)pi+pi- and Upsilon(2S)pi+pi- production near the Upsilon(5S) resonance

The Belle Collaboration; Chen, K. -F.; Hou, W. -S.; Shapkin, M.; al, A. Sokolov et
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We report the first observation of e+e- -> Upsilon(1S)pi+pi-, Upsilon(2S)pi+pi-, and first evidence for e+e- -> Upsilon(3S)pi+pi-, Upsilon(1S)K+K-, near the peak of the Upsilon(5S) resonance at sqrt{s}~10.87 GeV. The results are based on a data sample of 21.7 fb^-1 collected with the Belle detector at the KEKB e+e- collider. Attributing the signals to the Upsilon(5S) resonance, the partial widths Gamma(Upsilon(5S) -> Upsilon(1S) pi+pi-) = 0.59 +- 0.04 (stat) +- 0.09 (syst) MeV and Gamma(Upsilon(5S) -> Upsilon(2S) pi+pi-) = 0.85 +- 0.07 (stat) +- 0.16 (syst) MeV are obtained from the observed cross sections. These values exceed by more than two orders of magnitude the previously measured partial widths for dipion transitions between lower Upsilon resonances.; Comment: 6 pages, 4 figures, submit to PRL

Hadron physics potential of future high-luminosity B-factories at the Upsilon(5S) and above

Drutskoy, A. G.; Guo, Feng-Kun; Llanes-Estrada, Felipe J.; Nefediev, A. V.; Torres-Rincon, Juan M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We point out the physics opportunities of future high-luminosity B-factories at the Upsilon(5S) resonance and above. In this paper we discuss numerous interesting investigations, which can be performed in the e+e- centre-of-mass energy region from the Upsilon(5S) and up to 11.5 GeV, where an efficient data taking operation should be possible with the planned B-factories. These studies include abundant Bs production and decay properties; independent confirmation and if found, exhaustive exploration of Belle's claimed charged bottomonia; clarification of puzzles of interquarkonium dipion transitions; extraction of the light quark mass ratio from hadronic Upsilon(5S) decays; analysis of quarkonium and exotic internal structure from open flavour decays, leading to severe SU(3) symmetry violations; clarification of whether a hybrid state has similar mass to the Upsilon(5S) bottomonium, making it a double state; searches for molecular/tetraquark states that should be more stable with heavy quarks; completion of the table of positive-parity B_J mesons and study of their basic properties; production of Lambda_b\bar{Lambda}_b heavy baryon pairs, that, following weak decay, open vistas on the charmed baryon spectrum and new channels to study CP violation; confirmation or refutation of the deviation from pQCD of the pion transition form factor...

The anomalous Upsilon(1S)pi+pi- and Upsilon(2S)pi+pi- production near the Upsilon(5S) resonance

Chen, K. -F.; Collaboration, for the Belle
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/06/2008
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We report the study of e+e- -> Upsilon(1S)pi+pi-, Upsilon(2S)pi+pi-, Upsilon(3S)pi+pi-, and Upsilon(1S)K+K-, near the peak of the Upsilon(5S) resonance. The results are based on a data sample of 21.7 fb^-1 collected with the Belle detector at the KEKB e+e- collider. Attributing the signals to the Upsilon(5S) resonance, the partial widths Gamma(Upsilon(5S)->Upsilon(1S)pi+pi-) = 0.59+-0.04(stat)+-0.09(syst) MeV and Gamma(Upsilon(5S)->Upsilon(2S)pi+pi-) = 0.85+-0.07(stat)+-0.16(syst) MeV are obtained from the observed cross sections. These values exceed by more than two orders of magnitude the previously measured partial widths for dipion transitions between lower Upsilon resonances.; Comment: 6 pages, 5 figures, proceedings for Moriond QCD 2008

Y(5S) Results at Belle

Louvot, R.; collaboration, for the Belle
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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The data sample recorded with the Belle detector at the KEKB B factory (Tsukuba, Japan) operating at the Y(5S) energy provides interesting and new results about the Bs0 mesons and the Y(5S) resonance. Recent analyses, based on data samples collected at the Y(5S) resonance (23.6 /fb) or near it (7.9 /fb), are presented with a special focus on the final results on the Bs0 ->Ds- pi+ and Bs0 -> Ds-/+ K+/- decays, and on the intriguing Y(5S) -> Y(nS) pi+ pi- measurements.; Comment: 4 pages, 5 figures, contributed talk presented at the Lake Louise Winter Institute 2009 (Alberta, Canada), 16 - 21 February 2009. v2: values for f(Bs*Bs*), f(Bs*Bs) and f(BsBs) corrected