1,199 research outputs found
Lipase inhibition attenuates the acute inhibitory effects of oral fat on food intake in healthy subjects
The lipase inhibitor, orlistat, is used in the treatment of obesity and reduces fat absorption by about 30%. However, the mean weight loss induced by orlistat is less than expected for the degree of fat malabsorption. It was hypothesised that lipase inhibition with orlistat attenuates the suppressive effects of oral fat on subsequent energy intake in normal-weight subjects. Fourteen healthy, lean subjects (nine males, five females; aged 25 +/- 1.3 years) were studied twice, in a double-blind fashion. The subjects received a high-fat yoghurt 'preload' (males 400 g (2562 kJ); females 300 g (1923 kJ)), containing orlistat (120 mg) on one study day (and no orlistat on the other 'control' day), 30 min before ad libitum access to food and drinks; energy intake was assessed during the following 8 h. Blood samples were taken at regular intervals for the measurement of plasma cholecystokinin (CCK). Each subject performed a 3 d faecal fat collection following each study. Energy intake during the day was greater following orlistat (10,220 (SEM 928) kJ) v. control (9405 (SEM 824) kJ) (P=0.02). On both days plasma CCK increased (P<0.05) after the preload. Plasma CCK 20 min following ingestion of the preload was less after orlistat (4.1 (SEM 0.9) pmol/l) v. control (5.3 (SEM 0.9) pmol/l (P=0.028); however there was no difference in the area under the curve 0-510 min between the two study days. Fat excretion was greater following orlistat (1017 (SEM 168) kJ) v. control (484 (SEM 90) kJ) (P=0.004). In conclusion, in healthy, lean subjects the acute inhibitory effect of fat on subsequent energy intake is attenuated by orlistat and the increase in energy intake approximates the energy lost due to fat malabsorption.Deirdre OâDonovan, Christine Feinle-Bisset, Judith Wishart and Michael Horowit
Transverse mass and invariant mass observables for measuring the mass of a semi-invisibly decaying heavy particle
Formulae are derived for the positions of end-points in the invariant mass
and transverse mass distributions obtained from the products of heavy states
decaying to pairs of semi-invisibly decaying lighter states. Formulae are
derived both for the special case where the two decay chains are identical and
the more general case where they are different. The formulae are tested with a
simple case study of heavy SUSY higgs particles decaying to gauginos at the
LHC.Comment: 13 pages, 8 eps figure
Neutrino Oscillations from Supersymmetry without R-parity - Its Implications on the Flavor Structure of the Theory
We discuss here some flavor structure aspects of the complete theory of
supersymmetry without R-parity addressed from the perspective of fitting
neutrino oscillation data based on the recent Super-Kamiokande result. The
single-VEV parametrization of supersymmetry without R-parity is first reviewed,
illustrating some important features not generally appreciated. For the flavor
structure discussions, a naive, flavor model independent, analysis is
presented, from which a few interesting things can be learned.Comment: 1+10 pages latex, no figure; Invited talk at NANP 99 conference,
Dubna (Jun 28 - Jul 3) --- submission for the proceeding
Observation of a Spinning Top in a Bose-Einstein Condensate
Boundaries strongly affect the behavior of quantized vortices in
Bose-Einstein condensates, a phenomenon particularly evident in elongated
cigar-shaped traps where vortices tend to orient along a short direction to
minimize energy. Remarkably, contributions to the angular momentum of these
vortices are tightly confined to the region surrounding the core, in stark
contrast to untrapped condensates where all atoms contribute . We
develop a theoretical model and use this, in combination with numerical
simulations, to show that such localized vortices precess in an analogous
manner to that of a classical spinning top. We experimentally verify this
spinning-top behavior with our real-time imaging technique that allows for the
tracking of position and orientation of vortices as they dynamically evolve.
Finally, we perform an in-depth numerical investigation of our real-time
expansion and imaging method, with the aim of guiding future experimental
implementation, as well as outlining directions for its improvement.Comment: 10 pages, 7 figure
A Detailed Analysis of One-loop Neutrino Masses from the Generic Supersymmetric Standard Model
In the generic supersymmetric standard model which had no global symmetry
enforced by hand, lepton number violation is a natural consequence.
Supersymmetry, hence, can be considered the source of experimentally demanded
beyond standard model properties for the neutrinos. With an efficient
formulation of the model, we perform a comprehensive detailed analysis of all
one-loop contributions to neutrino masses.Comment: 27 pages Revtex, no figur
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