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We investigate the B meson light-cone distribution amplitudes in the heavyquark limit which are relevant for the QCD factorization approach for the exclusive B meson decays. We derive exact relations between twoand three-particle distribution amplitudes from the QCD equations of motion and heavy-quark symmetry constraint. As solution of these relations, we give representations for the quark-antiquark distribution amplitudes in terms of independent dynamical degrees of freedom. In particular, we find that the Wandzura-Wilczek-type contributions are determined uniquely in analytic form in terms ofΛ, a fundamental mass parameter of heavy-quark effective theory, and that both leading-and higher-twist distribution amplitudes receive the contributions of multi-particle states with additional gluons.DESY 01-135 HUPD-0108

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We investigate the Sudakov double logarithmic corrections to the form factor of fermion in the SU(2)⊗U(1) electroweak theory. We adopt the familiar Feynman gauge and present explicit calculations at the two loop level. We show that the leading logarithmic corrections coming from the infrared singularities are consistent with the "postulated" exponentiated electroweak Sudakov form factor. The similarities and differences in the "soft" physics between the electroweak theory and the unbroken non-abelian gauge theory (QCD) will be clarified.

We discuss the transverse momentum Q T distribution of Drell-Yan pair, produced in collisions of transversely polarized protons. We calculate the transversely polarized DrellYan cross section up to O(α s ) in the dimensional regularization, which gives QCD prediction at large Q T . For small Q T , we include all-orders resummation of large logarithms due to emission of soft gluons up to next-to-leading logarithmic accuracy. At intermediate Q T , the resummation formula is matched with the fixed-order α s perturbative results in a systematic way, and we derive the cross section with uniform accuracy over the entire range of Q T .Hard processes with polarized beams and/or target enable us to study spindependent dynamics of QCD. The helicity distribution ∆q(x) of quarks inside nucleon has been measured in polarized DIS experiments, and also ∆G(x) of gluon has been estimated from the scaling violations of them. On the other hand, the transversity distribution δq(x), i.e. the distribution of transversely polarized quarks inside transversely polarized nucleon, cannot be measured in the inclusive DIS due to its chiral-odd nature, 1) and remains as the last unknown distribution at the leading twist. Transversely polarized Drell-Yan (tDY) process is one of the processes where δq(x) can be measured, and has been undertaken at RHIC-Spin experiment. 2)We develop the QCD prediction of tDY cross section, dσ/dQ 2 dQ 2 T dydφ, differential in the transverse momentum Q T and rapidity y of the produced lepton pair, as well as in the dilepton invariant mass Q and in the azimuthal angle φ of one of the leptons with respect to the incoming nucleon's spin axis. Although this Q T -and y-differential cross section is fundamental in view of comparison with experiment, the corresponding formula has been unknown so far even in the leading order (LO) in QCD: the lepton-pair production with finite Q T via the Drell-Yan mechanism has to be accompanied by the radiation of at least one recoiling parton, so the LO term of the cross section is of O(α s ). The corresponding one-loop calculation of the LO term requires the phase space integration separating out the relevant transverse degrees of freedom, to extract the cos(2φ) dependence which is characteristic of the spin-dependent cross section of tDY. 1) In the dimensional regularization, in particular, the relevant phase space integration in D-dimension is rather cumbersome compared with unpolarized and longitudinally polarized cases. Furthermore, at small Q T ("edge regions of the phase space"), the radiation of soft gluon produces

The contribution of quarks with masses m Λ QCD is the only part of the structure functions in deepinelastic scattering (DIS) which is not yet known at the next-to-next-to-leading order (NNLO) of perturbative QCD. We present improved partial NNLO results for the most important structure function F 2 (x, Q 2 ) near the partonic threshold, in the high-energy (small-x) limit and at high scales Q 2 m 2 ; and employ these results to construct approximations for the gluon and quark coefficient functions which cover the full kinematic plane. The approximation uncertainties are carefully investigated, and found to be large only at very small values, x 10 −3 , of the Bjorken variable.

Summary Rice seed endosperm has two types of protein bodies (PB). Type I protein body (PB-I) accumulates prolamin and is hard to digest, while type II protein body (PB-II) mainly consists of glutelin, an easily digestible protein. A simple method to process rice protein and improve its digestibility was tested from the viewpoint of its application to food manufacturing. Rice protein prepared by alkaline extraction followed by neutralization sedimentation (AE-RP) was compared with that prepared by starch degradation by ␣ -amylase (SD-RP). The crude protein content of AE-RP and SD-RP was 84.7% and 78.2%, respectively. There were no major differences in protein composition among AE-RP, SD-RP and rice flour by SDS-PAGE, except 16 kDa polypeptide. With respect to amino acids, all the groups showed quite similar compositions, although cysteine and methionine were lower in AE-RP. In an in vitro digestion study with pepsin and pancreatin, both the SDS-PAGE analysis of protein pattern and the crude protein content of undigested residue clearly demonstrated that AE-RP has a higher digestibility than SD-RP. To find the cause of the difference in digestibility, the structural property of protein bodies by two production methods was compared using electron microscopy. PB-II of AE-RP was transformed into small, amorphous granules, while that of SD-RP was still kept partial protein body structures. PB-I of AE-RP kept its protein body structure, but produced double layers. From the finding that glutelin-gold was detected by immunochemistry not only in small, amorphous granules but also in PB-I, mainly the cortex layer, in AE-RP, it became clear that PB-I was swollen and fragile as a result of alkali treatment. These results strongly indicate that the improvement in digestibility of AE-RP is a result of the structural change of PB-I and -II caused by alkaline extraction.