Isometric exercise-induced hemodynamic load strongly predicts left ventricular mass in hypertension

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Constraints on quark energy loss from Drell-Yan data

A leading-order analysis of E866/NuSea and NA3 Drell-Yan data in nuclei is carried out. At Fermilab energy, the large uncertainties in the amount of sea quark shadowing prohibit clarifying the origin of the nuclear dependence observed experimentally. On the other hand, the small shadowing contribution to the Drell-Yan process in pi- A collisions at SPS allows one to set tight constraints on the energy loss of fast quarks in nuclear matter. We find the transport coefficient to be q = 0.24+/-0.18 GeV/fm^2 that corresponds to a mean energy loss per unit length -dE/dz = 0.20+/-0.15 GeV/fm for E > 50 GeV quarks in a large (A=200) nucleus.Comment: 14 pages, 2 figures. New modelling of the quenching, conclusions unchanged. Accepted for publication in Phys. Lett.

Threshold resummation of Drell-Yan rapidity distributions

We present a derivation of the threshold resummation formula for the Drell-Yan rapidity distribution. Our argument is valid for all values of rapidity and to all orders in perturbative QCD and can be applied to all Drell-Yan processes in a universal way, i.e. both for the production of a virtual photon \gamma^{*} and the production of a vector boson W^{\pm}, Z^{0}. We show that for the fixed-target experiment E866/NuSea used in current parton fits, the NLL resummation corrections are comparable to NLO fixed-order corrections and are crucial to obtain agreement with the data.Comment: 10 pages, 3 figures, Final versio

Implications of Scaling Violations of F2 at HERA for Perturbative QCD

We critically examine the QCD predictions for the $Q^2$ dependence of the electron-proton deep-inelastic structure function $F_2(x,Q^2)$ in the small $x$ region, which is being probed at HERA. The standard results based on next-to-leading order Altarelli-Parisi evolution are compared with those that follow from the BFKL equation, which corresponds to the resummation of the leading log$(1/x)$ terms. The effects of parton screening are also quantified. The theoretical predictions are confronted with each other, and with existing data from HERA. (3 Postscript figures included).Comment: (8 Latex Pages) IFJ 1653/P

The Pion Structure Function in a Constituent Model

Using the recent relatively precise experimental results on the pion structure function, obtained from Drell--Yan processes, we quantitatively test an old model where the structure function of any hadron is determined by that of its constituent quarks. In this model the pion structure function can be predicted from the known nucleon structure function. We find that the data support the model, at least as a good first approximation.Comment: 9 pages, 3 figure