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Large radiative corrections modify the predictions of the minimal supersymmetric extension of the standard model (MSSM) sufficiently for the constraints on this model, formerly derived from the searches for the CP-even h and for the CP-odd A neutral Higgs bosons, to be invalidated. In particular, the new h->AA decay mode has to be considered. The results presented here have been obtained from a data sample corresponding to about 185000 hadronic Z decays collected by the ALEPH experiment at LEP. No indication for any signal of the reactions e +e - -> hZ* or e +e - -> hA was found. A domain in the (m_h, m_A) plane is thus excluded at 95% CL in a large class of two-Higgs-doublet models. More restrictive results are derived in the MSSM, with one loop radiative corrections to the Higgs potential taken into account. It is found that m_h > 41 GeV/c(2) and m_A >20 GeV/c(2) at 95% CL when the other parameters of the model are varied in their allowed ranges

Accurate quantification of metabolites by nuclear magnetic resonance (NMR) is of prime importance in the field of health sciences for understanding the metabolic pathways of the investigated system, to address the mechanisms of action of diseases, and improving their diagnosis, treatment, and prognosis. Unfortunately, the absolute quantitative analysis of complex samples is still limited by sensitivity and resolution issues that are intrinsic to this technique. Ultrahigh-resolution pure shift methods have especially shown to be suitable for interpreting mixtures of metabolites in biological samples. Here, we introduce a robust analytical protocol based on the use of a pure shift library of calibration reference spectra to fit the fingerprint of each metabolite of interest and determine its concentration. The approach based on the SAPPHIRE pulse sequence enhanced with a block for solvent suppression has been validated through the results of a series of model mixtures, exhibiting excellent trueness (slope values in the range of 0.93–1.02) and linearity (R 2 > 0.996) in a total time (a few hours) that is fully compatible with metabolomics studies. Furthermore, we have successfully applied our method to determine the absolute metabolite concentrations in a lymphoma extracellular medium, which improves metabolomic protocols reported to date by providing a quantitative and highly resolved vision of metabolic processes at play.

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B s b yservtion of the emileptoni heys of nd à rdrons t vi aleph lep 2

In a sample of 190000 hadronic Z decays, three signals of charm production are observed: two from the exclusive decays D0-> k- pi+ and D*+-> D0 pi+ with D0pi+ -> K-pi+pi+ and one in the transverse-momentum distribution of soft hadrons relative to the nearest jet. The features of these signals are in good agreement with expectations based on the standard model and previous measurements of the branching fractions. The number of D*+/- -> K-/+ pi+/- pi+/- per hadronic decay of the Z is measured to be (5.11 +/- 0.34)x 10^-3, and the branching ratio B (D0 ->K -pi+) is (3.62 +/- 0.34 +/- 0.44)%. Charm hadronization has been studied. The average fraction of the beam energy carried by the D* meson is found to be c = 0.504 -0.017 +0.013 +/- 0.008, and implications of the measurements on the pseudoscalar-to-vector production ratio of charmed mesons are discussed

The production of high energy isolated photons in hadronic Z decays is measured with the ALEPH detector at LEP using a sample of 180 000 hadronic events. Such photons are mainly radiated by quarks, thus giving direct insights into the early parton showering mechanism. The observed rate is compared with a QCD calculation of final state radiation from quarks

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