RESUMEN
The KTeV E799 experiment has conducted a search for the rare decays, K(L)âπ(0)π(0)µ(+)µ(-) and K(L)âπ(0)π(0)X(0)âπ(0)π(0)µ(+)µ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of Br(K(L)âπ(0)π(0)X(0)âπ(0)π(0)µ(+)µ(-)) < 1.0 × 10(-10) and Br(K(L)âπ(0)π(0)µ(+)µ(-)) < 9.2 × 10(-11) at the 90% confidence level. This result rules out the pseudoscalar X(0) as an explanation of the HyperCP result under the scenario that the dsX(0) coupling is completely real.
RESUMEN
The E799-II (KTeV) experiment at Fermilab has collected 83 262 K(L)-->e+ e- gamma(gamma) events above a background of 79 events. We measure a decay width, normalized to the K(L)-->pi0pi0pi(D)0 (pi0-->gammagamma, pi0-->gammagamma, pi(D0-->e+ e- gamma(gamma)) decay width, of Gamma(K(L)-->e+e-gamma(gamma))/Gamma(K(L)-->pi0pi0pi(D)0)=(1.3302+/-0.0046(stat)+/-0.0102(syst)) x 10(-3). We also measure parameters of two K(L)gamma*gamma form factor models. In the Bergström-Massó-Singer parametrization, we find Calpha(K*)= -0.517 +/- 0.030(stat) +/- 0.022(syst). We separately fit for the first parameter of the D'Ambrosio-Isidori-Portolés model and find alpha(DIP)= -1.729 +/- 0.043(stat) +/- 0.028(syst).
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This article argues the need for research in a feminist gerontology that is informed by postmodern and poststructuralist theories. Feminist gerontology is defined and described as part of a larger movement in the field toward critical gerontology. A brief summary of postmodern thought is followed by questions for researchers in gerontology and guidelines for feminist research which is interpretive, interactive, critical, and change-oriented.
Asunto(s)
Envejecimiento , Feminismo , Geriatría , Filosofía , Proyectos de Investigación , Salud de la Mujer , Anciano , Femenino , Humanos , Conocimiento , Lenguaje , Variaciones Dependientes del ObservadorAsunto(s)
Antiinflamatorios/síntesis química , Oxadiazoles/síntesis química , Sidnonas/síntesis química , Adyuvantes Inmunológicos , Animales , Antiinflamatorios/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/inmunología , Hidrocortisona/uso terapéutico , Masculino , Mycobacterium/inmunología , Ratas , Relación Estructura-Actividad , Sidnonas/uso terapéuticoAsunto(s)
Culpa , Libido , Personalidad , Conducta Sexual , Adulto , Literatura Erótica , Femenino , Humanos , Autoimagen , Factores Sexuales , Percepción VisualAsunto(s)
Literatura Erótica , Respuesta Galvánica de la Piel , Culpa , Frecuencia Cardíaca , Personalidad , Percepción Visual , Adulto , Nivel de Alerta , Coito , Femenino , Humanos , Masturbación , Inventario de PersonalidadRESUMEN
The Fermilab KTeV experiment has searched for lepton-flavor-violating decays of the K(L) meson in three decay modes. We observe no events in the signal region for any of the modes studied, and we set the following upper limits for their branching ratios at the 90% C.L.: BR(K(L) --> pi(0) micro(+/-) e(-/+)) <7.6 x 10(-11); BR(K(L) --> pi(0)pi(0) micro(+/-) e(-/+)) <1.7 x 10(-10); BR(pi(0) --> micro(+/-) e(-/+)) <3.6 x 10(-10). This result represents a factor of 82 improvement in the branching ratio limit for K(L) --> pi(0) micro(+/-) e(-/+) and is the first reported limit for K(L) --> pi(0)pi(0) micro(+/-) e(-/+).
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We present a new determination of the parity of the neutral pion via the double Dalitz decay pi0-->e+e-e+e-. Our sample, which consists of 30,511 candidate decays, was collected from KL-->pi0pi0pi0 decays in flight at the KTeV-E799 experiment at Fermi National Accelerator Laboratory. We confirm the negative pi0 parity and place a limit on scalar contributions to the pi0-->e+e-e+e- decay amplitude of less than 3.3% assuming CPT conservation. The pi0gamma*gamma* form factor is well described by a momentum-dependent model with a slope parameter fit to the final state phase-space distribution. Additionally, we have measured the branching ratio of this mode to be B(pi0-->e+e-e+e-)=(3.26+/-0.18)x10(-5).
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This Letter is the first report of the K{L}-->pi{+/-}e{-/+}nue{+}e{-} decay. Based on 19 208+/-144 events, we determine the branching fraction, B(K{L}-->pi{+/-}e{-/+}nue{+}e{-}M_{e{+}e{-}}>5 MeV/c{2},E{e{+}e{-}}{*}>30 MeV)=(1.285+/-0.041)x10{-5}, and Gamma(K{e3ee}M{e{+}e{-}}>5 MeV/c{2})/Gamma(K{e3})=[4.57+/-0.04(stat)+/-0.14(syst)]x10{-5}. This ratio agrees with a theoretical prediction based on chiral perturbation theory (ChPT) calculated to O(p{4}). The measured kinematical distributions agree with those predicted by just ChPT O(p{4}), but show significant disagreement with ones predicted by leading-order ChPT.
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Using the complete KTeV data set of 5,241 candidate K(L)--> pi(+) pi(-) e(+) e(-) decays (including an estimated background of 204 +/- 14 events), we have measured the coupling g(CR)= 0.163 +/- 0.0149(stat) +/- 0.023(syst) of the CP conserving charge radius process and from it determined a K(0) charge radius of
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The xi0 muon semileptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the xi0 beta decay mode and yields a value for the ratio of decay rates gamma(xi0 --> sigma+ mu- nu(mu))/gamma(xi0 --> sigma+ e- nu(e)) of [1.8(-0.5)(+0.7)(stat) +/- 0.2(syst)] x 10(-2). This is in agreement with the SU(3) flavor symmetric quark model.
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This article defines "empowering research" and argues the need for a critical gerontology informed by feminist and postmodern theories which focus on the connections between language, self, and social action. The author calls for feminist gerontology which evokes critical consciousness on the part of the researcher and participants. Feminist gerontologists are encouraged to engage in self-reflection and self-critique in regards to their own attitudes toward aging and to include personal criticism in their scholarly writings. Examples of feminist research on aging which illustrate these characteristics are provided.
Asunto(s)
Feminismo , Geriatría/métodos , Salud de la Mujer , Anciano , Femenino , Humanos , Formulación de Políticas , Proyectos de Investigación , Estados UnidosRESUMEN
A disaccharide was isolated from rat mammary tissue and determined to be 6-O-beta-galactopyranosyl myo-inositol (6-beta-galactinol) on the basis of combined gas-liquid chromatography-mass spectrometry of the permethylated and peracetylated derivatives as well as previously reported chemical and enzymatic evidence. 6-beta-Galactinol, also found in rat milk, increased during lactation, and on the 18th day represented approximately 17% of the total non-lipid neutral myo-inositol. The sugar was absent in all other rat tissues examined, suggesting a unique association with the process of lactation. This novel galactoside of one human subject on the basis of paper and gas-liquid chromatography.
Asunto(s)
Disacáridos/análisis , Galactosa/análisis , Inositol/análisis , Animales , Cromatografía de Gases , Calostro/análisis , Disacáridos/aislamiento & purificación , Femenino , Humanos , Lactancia , Glándulas Mamarias Animales/metabolismo , Espectrometría de Masas , Leche/análisis , Leche Humana/análisis , Conformación Molecular , Embarazo , RatasRESUMEN
Neonatal rats of the Holtzman strain, 6 days of age, were fed a myo-inositol restricted liquid formula by gastric intubation for 10 days, after which they were fed a purified myo-inositol-free diet until they were 72 days old. No differences in weight gain were observed between myo-inositol/100 ml of formula or 150 mg myo-inositol/100 g diet. Most tissues examined from rats fed the myo-inositol deprived formula and diet had lower free myo-inositol levels than the controls with the exception of the liver. Despite reduced free and lipid-bound myo-inositol in the liver, there was no evidence of fatty liver in the young rats at any age. The cerebrum and cerebellum of myo-inositol deprived rats had normal myelination and mitochondriogenesis as judged by the levels of 2',3'-cyclic nucleotide-3'-phosphohydrolase (EC 3.1.4.1) and fumarase (EC 4.2.1.2) activity, respectively.
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Inositol , Deficiencia de Vitamina B/metabolismo , 2',3'-Nucleótido Cíclico Fosfodiesterasas/metabolismo , Factores de Edad , Animales , Animales Recién Nacidos , Peso Corporal , Encéfalo/metabolismo , Femenino , Fumarato Hidratasa/metabolismo , Inositol/metabolismo , Inositol/uso terapéutico , Intestino Delgado/metabolismo , Riñón/metabolismo , Cristalino/metabolismo , Hígado/metabolismo , Pulmón/metabolismo , Masculino , Miocardio/metabolismo , Ratas , Testículo/metabolismo , Deficiencia de Vitamina B/tratamiento farmacológicoRESUMEN
The KTeV experiment at Fermilab has isolated a total of 132 events from the rare decay K(L)-->e+ e- mu+ mu-, with an estimated background of 0.8 events. The branching ratio of this mode is determined to be [2.69+/-0.24(stat)+/-0.12(syst)]x10(-9), with a radiative cutoff of M(2)(ee mu mu)/M(2)(K)>0.95. The first measurement using this mode of the parameter alpha from the D'Ambrosio-Isidori-Portolès (DIP) model of the K(L)gamma*gamma* vertex yields a result of -1.59+/-0.37, consistent with values obtained from other decay modes. Because of the limited statistics, no sensitivity is found to the DIP parameter beta. We use this decay mode to set limits on CP and lepton violation.
RESUMEN
We present a determination of the Cabibbo-Kobayashi-Maskawa parameter |V(us)| based on new measurements of the six largest K(L) branching fractions and semileptonic form factors by the KTeV (E832) experiment at Fermilab. We find |V(us)|=0.2252+/-0.0008(KTeV)+/-0.0021(ext), where the errors are from KTeV measurements and from external sources. We also use the measured branching fractions to determine the CP violation parameter |eta(+-)|=(2.228+/-0.005(KTeV)+/-0.009(ext))x10(-3).
RESUMEN
The KTeV/E799 experiment at Fermilab has searched for the rare kaon decay K(L)-->pi(0)e(+)e(-). This mode is expected to have a significant CP violating component. The measurement of its branching ratio could support the standard model or could indicate the existence of new physics. This Letter reports new results from the 1999-2000 data set. One event is observed with an expected background at 0.99+/-0.35 events. We set a limit on the branching ratio of 3.5x10(-10) at the 90% confidence level. Combining with the previous result based on the data set taken in 1997 yields the final KTeV result: BR(K(L)-->pi(0)e(+)e(-))<2.8x10(-10) at 90% C.L.