Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Osteoporos Int ; 25(8): 2027-33, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24803329

RESUMEN

UNLABELLED: In this longitudinal case-control study, acute fracture was associated with low serum testosterone, which was transient in 43% of men. While assessment of gonadal status is part of the assessment of bone fragility, measurement of testosterone in the early period after fracture may overestimate the prevalence of androgen deficiency. INTRODUCTION: Measurement of circulating testosterone is recommended in the evaluation of bone fragility in men. Since acute illness can transiently decrease circulating testosterone, we quantified the association of acute fracture and serum testosterone levels. METHODS: A case-control study was conducted involving 240 men with a radiologically confirmed minimal trauma fracture presenting to a tertiary referral hospital and 89 age-matched men without a history of minimal trauma fracture serving as controls. Follow-up testosterone levels 6 months after baseline were available for 98 cases and 27 controls. Results were expressed as the median and interquartile (IQR) range. RESULTS: Compared to controls, cases had lower total testosterone [TT, 7.2 (3.5, 10.8) vs 13.6 (10.9, 17.1) nmol/L, p < 0.001]. The 143 cases treated as inpatients had lower testosterone levels than the 97 cases treated as outpatients [TT 4.7 (2.3, 8.1) vs 10.3 (7.5, 12.7) nmol/L, p < 0.001]. Group differences in calculated free testosterone (cFT) were comparable to the group differences in TT. At follow-up, in 98 cases, median TT increased from 6.5 nmol/L (3.2, 8.5) to 9.6 nmol/L (6.9, 12.0) p < 0.0001, and SHBG remained unchanged. Of cases with low testosterone, 43% with TT <10 nmol/L and/or cFT <230 pmol/L at presentation were reclassified as androgen sufficient at follow-up. TT was unchanged in the controls. CONCLUSIONS: Low testosterone levels in men presenting with an acute fracture may, at least in part, be due to an acute, fracture-associated, stress response. To avoid over diagnosis, evaluation for testosterone deficiency should be deferred until recovery from the acute event.


Asunto(s)
Fracturas Osteoporóticas/sangre , Testosterona/sangre , Absorciometría de Fotón/métodos , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Densidad Ósea/fisiología , Estudios de Casos y Controles , Comorbilidad , Estudios de Seguimiento , Articulación de la Cadera/fisiopatología , Humanos , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/fisiopatología , Testosterona/deficiencia
2.
J Cell Biol ; 142(6): 1487-99, 1998 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-9744879

RESUMEN

A morphogenesis checkpoint in budding yeast delays cell cycle progression in response to perturbations of cell polarity that prevent bud formation (Lew, D.J., and S.I. Reed. 1995. J. Cell Biol. 129:739- 749). The cell cycle delay depends upon the tyrosine kinase Swe1p, which phosphorylates and inhibits the cyclin-dependent kinase Cdc28p (Sia, R.A.L., H.A. Herald, and D.J. Lew. 1996. Mol. Biol. Cell. 7:1657- 1666). In this report, we have investigated the nature of the defect(s) that trigger this checkpoint. A Swe1p- dependent cell cycle delay was triggered by direct perturbations of the actin cytoskeleton, even when polarity establishment functions remained intact. Furthermore, actin perturbation could trigger the checkpoint even in cells that had already formed a bud, suggesting that the checkpoint directly monitors actin organization, rather than (or in addition to) polarity establishment or bud formation. In addition, we show that the checkpoint could detect actin perturbations through most of the cell cycle. However, the ability to respond to such perturbations by delaying cell cycle progression was restricted to a narrow window of the cell cycle, delimited by the periodic accumulation of the checkpoint effector, Swe1p.


Asunto(s)
Actinas/metabolismo , Proteínas Tirosina Quinasas/fisiología , Saccharomyces cerevisiae/fisiología , Transducción de Señal , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Ciclo Celular , Proteínas de Ciclo Celular , Núcleo Celular/efectos de los fármacos , Citoesqueleto/metabolismo , Morfogénesis , Proteínas Tirosina Quinasas/genética , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae , Tiazoles/farmacología , Tiazolidinas
3.
Mol Cell Biol ; 15(10): 5279-87, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7565676

RESUMEN

Ime2p is a protein kinase that is expressed only during meiosis in Saccharomyces cerevisiae. Ime2p stimulates early, middle, and late meiotic gene expression and down-regulates expression of IME1, which specifies an activator of early meiotic genes that acts independently of Ime2p. We have identified a new gene, IDS2 (for IME2-dependent signaling), which has a functional relationship to Ime2p. An ids2 null mutation delays down-regulation of IME1 and expression of middle and late meiotic genes. In an ime1 null mutant that express IME2 from the GAL1 promoter (ime1 delta PGAL1-IME2 mutant), early meiotic gene expression depends only upon Ime2p. In such strains, Ids2p is dispensable for expression of the early genes HOP1 and SPO13 but is essential for expression of the middle and late genes SPS1, SPS2, and SPS100. Ids2p is also essential for the autoregulatory pathway through which Ime2p activates its own expression via the IME2 upstream activation sequences (UAS). An PGAL1-IME2 derivative that produces a truncated Ime2p (lacking its C-terminal 174 residues) permits IME2 UAS activation in the absence of Ids2p. This observation suggests that Ids2p acts upstream of Ime2p or that Ids2p and Ime2p act in independent, convergent pathways to stimulate IME2 UAS activity. Accumulation of epitope-tagged Ids2p derivatives is greatest in growing cells and declines during meiosis. We propose that Ids2p acts indirectly to modify Ime2p activity, thus permitting Ime2p to carry out later meiotic functions.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas Fúngicas/fisiología , Regulación Fúngica de la Expresión Génica/fisiología , Meiosis/genética , Proteínas Quinasas/fisiología , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Factores de Transcripción , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Genes Fúngicos/genética , Ligamiento Genético , Péptidos y Proteínas de Señalización Intracelular , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Proteínas Quinasas/genética , Proteínas Serina-Treonina Quinasas , Proteínas Recombinantes de Fusión , Secuencias Reguladoras de Ácidos Nucleicos/genética , Saccharomyces cerevisiae/fisiología , Análisis de Secuencia de ADN , Transducción de Señal , Esporas Fúngicas , Supresión Genética
4.
Mol Cell Biol ; 19(9): 5981-90, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10454545

RESUMEN

The morphogenesis checkpoint in budding yeast delays cell cycle progression in G(2) when the actin cytoskeleton is perturbed, providing time for cells to complete bud formation prior to mitosis. Checkpoint-induced G(2) arrest involves the inhibition of the master cell cycle regulatory cyclin-dependent kinase, Cdc28p, by the Wee1 family kinase Swe1p. Results of experiments using a nonphosphorylatable CDC28(Y19F) allele suggested that the checkpoint stimulated two inhibitory pathways, one that promoted phosphorylation at tyrosine 19 (Y19) and a poorly characterized second pathway that did not require Cdc28p Y19 phosphorylation. We present the results from a genetic screen for checkpoint-defective mutants that led to the repeated isolation of the dominant CDC28(E12K) allele that is resistant to Swe1p-mediated inhibition. Comparison of this allele with the nonphosphorylatable CDC28(Y19F) allele suggested that Swe1p is still able to inhibit CDC28(Y19F) in a phosphorylation-independent manner and that both the Y19 phosphorylation-dependent and -independent checkpoint pathways in fact reflect Swe1p inhibition of Cdc28p. Remarkably, we found that a Swe1p mutant lacking catalytic activity could significantly delay the cell cycle in vivo during a physiological checkpoint response, even when expressed at single copy. The finding that a Wee1 family kinase expressed at physiological levels can inhibit a nonphosphorylatable cyclin-dependent kinase has broad implications for many checkpoint studies using such mutants in other organisms.


Asunto(s)
Proteína Quinasa CDC28 de Saccharomyces cerevisiae/antagonistas & inhibidores , Proteína Quinasa CDC28 de Saccharomyces cerevisiae/genética , Ciclo Celular , Proteínas Tirosina Quinasas/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/enzimología , Alelos , Secuencia de Bases , Ciclo Celular/genética , Ciclo Celular/fisiología , Proteínas de Ciclo Celular , Cartilla de ADN/genética , Fase G2 , Genes Fúngicos , Mutación , Fosforilación , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae
5.
Mol Cell Biol ; 19(10): 6929-39, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10490630

RESUMEN

In Saccharomyces cerevisiae, the Wee1 family kinase Swe1p is normally stable during G(1) and S phases but is unstable during G(2) and M phases due to ubiquitination and subsequent degradation. However, perturbations of the actin cytoskeleton lead to a stabilization and accumulation of Swe1p. This response constitutes part of a morphogenesis checkpoint that couples cell cycle progression to proper bud formation, but the basis for the regulation of Swe1p degradation by the morphogenesis checkpoint remains unknown. Previous studies have identified a protein kinase, Hsl1p, and a phylogenetically conserved protein of unknown function, Hsl7p, as putative negative regulators of Swe1p. We report here that Hsl1p and Hsl7p act in concert to target Swe1p for degradation. Both proteins are required for Swe1p degradation during the unperturbed cell cycle, and excess Hsl1p accelerates Swe1p degradation in the G(2)-M phase. Hsl1p accumulates periodically during the cell cycle and promotes the periodic phosphorylation of Hsl7p. Hsl7p can be detected in a complex with Swe1p in cell lysates, and the overexpression of Hsl7p or Hsl1p produces an effective override of the G(2) arrest imposed by the morphogenesis checkpoint. These findings suggest that Hsl1p and Hsl7p interact directly with Swe1p to promote its recognition by the ubiquitination complex, leading ultimately to its destruction.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/citología , Ciclo Celular/fisiología , Modelos Biológicos , Morfogénesis , Periodicidad , Fosforilación , Unión Proteica , Proteínas Serina-Treonina Quinasas , Proteína-Arginina N-Metiltransferasas , Saccharomyces cerevisiae/metabolismo
6.
Mol Biol Cell ; 7(11): 1657-66, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8930890

RESUMEN

A morphogenesis checkpoint in budding yeast delays nuclear division (and subsequent cell cycle progression) in cells that have failed to make a bud. We show that the ability of this checkpoint to delay nuclear division requires the SWE1 gene, encoding a protein kinase that inhibits the master cell cycle regulatory kinase Cdc28. The timing of nuclear division in cells that cannot make a bud is exquisitely sensitive to the dosage of SWE1 and MIH1 genes, which control phosphorylation of Cdc28 at tyrosine 19. In contrast, the timing of nuclear division in budded cells does not rely on Cdc28 phosphorylation, suggesting that the morphogenesis checkpoint somehow turns on this regulatory pathway. We show that SWE1 mRNA levels fluctuate during the cell cycle and are elevated in cells that cannot make a bud. However, regulation of SWE1 mRNA levels by the checkpoint is indirect, acting through a feedback loop requiring Swe1 activity. Further, the checkpoint is capable of delaying nuclear division even when SWE1 transcription is deregulated. We propose that the checkpoint delays nuclear division through post-translational regulation of Swe1 and that transcriptional feedback loops enhance the efficacy of the checkpoint.


Asunto(s)
Proteína Quinasa CDC28 de Saccharomyces cerevisiae/metabolismo , Ciclina B , Factores de Intercambio de Guanina Nucleótido , Mitosis , Proteínas Tirosina Quinasas/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/fisiología , Ciclinas/genética , Ciclinas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Morfogénesis , Mutación , Fosforilación , Fosfotirosina/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/fisiología , ARN de Hongos/genética , ARN de Hongos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Transcripción Genética
7.
Genetics ; 133(4): 775-84, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8462841

RESUMEN

IME1 is required in yeast for meiosis and for expression of IME2 and other early meiotic genes. IME1 is a 360-amino acid polypeptide with central and C-terminal tyrosine-rich regions. We report here that a fusion protein composed of the lexA DNA-binding domain and IME1 activates transcription in vivo of a reporter gene containing upstream lexA binding sites. Activation by the fusion protein shares several features with natural IME1 activity: both are dependent on the RIM11 gene product; both are impaired by the same ime1 missense mutations; both are restored by intragenic suppressors. The central tyrosine-rich region is sufficient to activate transcription when fused to lexA. Deletion of this putative activation domain results in a defective IME1 derivative. Function of the deletion derivative is restored by fusion to the acidic Herpesvirus VP16 activation domain. The C-terminal tyrosine-rich region is dispensable for transcriptional activation; rather it renders activation dependent upon starvation and RIM11. Immunofluorescence studies indicate that an IME1-lacZ fusion protein is concentrated in the nucleus. These observations are consistent with a model in which IME1 normally stimulates IME2 expression by providing a transcriptional activation domain at the IME2 5' regulatory region.


Asunto(s)
Proteínas Fúngicas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Serina Endopeptidasas , Factores de Transcripción , Transcripción Genética , Activación Transcripcional , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Mutación , Proteínas Nucleares/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Saccharomyces cerevisiae/metabolismo , Relación Estructura-Actividad
8.
Ann Otol Rhinol Laryngol ; 90(4 Pt 1): 307-9, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7271139

RESUMEN

Intubation problems sometimes occur very suddenly and can be divided into two groups. The expected ones include the patients with a short neck and long teeth, cellulitis of the tongue, large oropharyngeal tumors, obstructing laryngeal tumors, congenital and acquired maxillofacial deformities, ankylosis of the temporomandibular joints, fractures or ankylosing spondylitis of the cervical spine, and all patients with a history of previous intubation problems. Unexpected problems can arise in patients who combine large incisors and canines with an inability to open the mouth wide, or when the glottis is invisible because the epiglottis is immobile. The first concern in these cases is to restore consciousness, for the conscious patient shows tonus and this facilitates identification of anatomical landmarks. A 60 cm bronchofiberscope provided with a tube and a freely movable end of 30 cm is suitable. Shorter flexible scopes are not adequate.


Asunto(s)
Broncoscopía , Intubación Intratraqueal/métodos , Broncoscopios , Tecnología de Fibra Óptica , Humanos , Intubación Intratraqueal/instrumentación , Materiales de Enseñanza
9.
Acta Anaesthesiol Belg ; 35(2): 165-87, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6149664

RESUMEN

A review is given of the pharmacodynamic effects of Ketamine and the commonly used Benzodiazepines especially regarding the clinical application of the substances in combination as socalled ataranalgesia. The literature as well as own experimental results show the advantages of ataranalgetic combinations for induction and maintenance of general anesthesia. Special comment is given for new results about the reversal of hypnotic action by means of 4-aminopyridine.


Asunto(s)
Anestesia/métodos , Ansiolíticos/administración & dosificación , Ketamina/administración & dosificación , 4-Aminopiridina , Aminopiridinas/farmacología , Animales , Benzodiazepinas , Combinación de Medicamentos , Corazón/efectos de los fármacos , Humanos , Ketamina/efectos adversos , Ketamina/metabolismo , Unión Neuromuscular/efectos de los fármacos
10.
Acta Anaesthesiol Belg ; 30 Suppl: 195-9, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-547661

RESUMEN

The analeptic agent, 4-aminopyridine, was given to patients who had undergone elective ear, nose and throat surgery and showed severe central respiratory depression due to intra-operative fentanyl administration. The respiratory depression due to fentanyl was found to be partially antagonised by 4-aminopyridine. In view of these preliminary findings it is suggested that the drug might find a use in combatting postoperative fentanyl-induced respiratory depression.


Asunto(s)
Aminopiridinas/uso terapéutico , Complicaciones Posoperatorias/tratamiento farmacológico , Insuficiencia Respiratoria/tratamiento farmacológico , Fentanilo/efectos adversos , Humanos , Respiración/efectos de los fármacos
14.
Phys Rev Lett ; 100(9): 091801, 2008 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-18352696

RESUMEN

We present measurements of D--> KS0 pi and D--> KL0 pi branching fractions using 281 pb(-1) of psi(3770) data at the CLEO-c experiment. We find that B(D0--> KS0 pi 0) is larger than B(D0--> KL0 pi 0), with an asymmetry of R(D0)=0.108+/-0.025+/-0.024. For B(D+--> KS0 pi+) and B(D+--> KL0 pi+), we observe no measurable difference; the asymmetry is R(D+)=0.022+/-0.016+/-0.018. The D0 asymmetry is consistent with the value based on the U-spin prediction A(D0--> K0 pi 0)/A(D0--> K0 pi 0)=-tan2 theta C, where theta C is the Cabibbo angle.

15.
Phys Rev Lett ; 101(20): 201601, 2008 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-19113327

RESUMEN

In this Letter, we describe a search for lepton flavor violation (LFV) in the bottomonium system. We search for leptonic decays Upsilon(nS)-->mutau (n=1, 2, and 3) using the data collected with the CLEO III detector. We identify the tau lepton using its leptonic decay nu_{tau}nu[over ]_{e}e and utilize multidimensional likelihood fitting with probability density function shapes measured from independent data samples. We report our estimates of 95% C.L. upper limits on LFV branching fractions of Upsilon mesons. We interpret our results in terms of the exclusion plot for the energy scale of a hypothetical new interaction versus its effective LFV coupling in the framework of effective field theory.

16.
J Environ Manage ; 82(1): 60-5, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16551490

RESUMEN

The presence of Escherichia coli in recreational and potable waters is a major concern to the general public as elevated levels of E. coli suggest the presence of pathogenic bacteria and viruses. Unfortunately, traditional microbial techniques do not allow specific identification of the source of E. coli. This reduces the ability to target management practices that reduce bacterial contamination. In the Finger Lakes region of western New York, USA, wildlife resides in relatively high densities on watersheds dominated by people and dairy farms, and as a result, the sources of fecal degradation of potable and recreational waters are often unknown. In the Conesus Lake watershed, the sources of microbial contamination were assessed using Rep-PCR molecular tools, a method of amplifying repetitive DNA sequences found throughout the E. coli genome to produce distinct fingerprints for a given ecotype. Molecular fingerprints of E. coli isolated from regional populations of cattle, humans, geese and deer were compared to E. coli isolated from stream water samples. Canonical discriminant function analysis indicated that the DNA fingerprints of the original source group isolates were correctly predicted 90.2% of the time. Since land use in the sub-watersheds was dominated by dairy and cash crop farms, it was expected that the majority of E. coli isolated would be identified as cows; however, an unexpectedly high percentage of isolates were identified as wildlife (geese and deer). Geese were the dominant source of E. coli (44.7-73.7% of the total sources) in four sub-watersheds followed by cows (10.5-21.1%), deer (10.5-18.4%), humans (5.3-12.9%) and unidentifiable sources (0.0-11.8%). Management practices intended to decrease the number of cattle or the amount of manure spread in a sub-watershed were reflected in a decrease of E. coli ecotypes associated with dairy cows.


Asunto(s)
Monitoreo del Ambiente/métodos , Escherichia coli/aislamiento & purificación , Heces/microbiología , Agua Dulce/microbiología , Microbiología del Agua , Agricultura , Animales , Bovinos , Dermatoglifia del ADN/métodos , Ciervos , Escherichia coli/patogenicidad , Gansos , Humanos , New York , Reacción en Cadena de la Polimerasa/métodos
17.
Phys Rev Lett ; 99(19): 191801, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-18233062

RESUMEN

Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions.

18.
Phys Rev Lett ; 99(19): 191805, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-18233066

RESUMEN

Using data collected near the D{s}{*+}D{s}{-} peak production energy E_{cm}=4170 MeV by the CLEO-c detector, we study the decays of D{s}{+} mesons to two pseudoscalar mesons. We report on searches for the singly Cabibbo-suppressed D{s}{+} decay modes K{+}eta, K{+}eta', pi{+}K{S}{0}, K{+}pi{0}, and the isospin-forbidden decay mode D{s}{+}-->pi{+}pi{0}. We normalize with respect to the Cabibbo-favored D{s}{+} modes pi{+}eta, pi{+}eta', and K{+}K{S}{0}, and obtain ratios of branching fractions: B(D{s}{+}-->K{+}eta)/B(D{s}{+}-->pi{+}eta)=(8.9+/-1.5+/-0.4)%, B(D{s}{+}-->K{+}eta')/B(D{s}{+}-->pi{+}eta')=(4.2+/-1.3+/-0.3)%, B(D{s}{+}-->pi{+}K{S}{0})/B(D{s}{+}-->K{+}K{S}{0})=(8.2+/-0.9+/-0.2)%, B(D{s}{+}-->K{+}pi{0})/B(D{s}{+}-->K{+}K{S}{0})=(5.5+/-1.3+/-0.7)%, and B(D{s}{+}-->pi{+}pi{0})/B(D{s}{+}-->K{+}K{S}{0})<4.1% at 90% C.L., where the uncertainties are statistical and systematic, respectively.

19.
Phys Rev Lett ; 99(12): 122001, 2007 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-17930497

RESUMEN

The decay psi(2S) --> etaJ/psi is used to measure, for the first time, all prominent eta-meson branching fractions with the same experiment in the same dataset, thereby providing a consistent treatment of systematics across branching fractions. We present results for eta decays to gamma gamma, pi(+)pi(-)pi(0), 3pi(0), pi(+)pi(-)gamma and e(+)e(-)gamma, accounting for 99.9% of all eta decays. The precision of several of the branching fractions and their ratios is improved. Two channels, pi(+)pi(-)gamma and e(+)e(-)gamma, show results that differ at the level of three standard deviations from those previously determined.

20.
Phys Rev Lett ; 99(12): 122002, 2007 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-17930498

RESUMEN

We measure the mass of the eta meson using psi(2S) --> etaJ/psi events acquired with the CLEO-c detector operating at the CESR e(+)e(-) collider. Using the four decay modes eta --> gamma gamma, 3pi(0), pi(+)pi(-)pi(0), and pi(+)pi(-)gamma, we find M(eta) = 547.785 +/- 0.017 +/- 0.057 MeV, in which the first uncertainty is statistical and the second systematic. This result has an uncertainty comparable to the two most precise previous measurements and is consistent with that of NA48, but is inconsistent at the level of 6.5 sigma with the much smaller mass obtained by GEM.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA