74 research outputs found
Twist-3 Effects in Polarized Photon Structure
The polarized photon structure is described by two spin structure functions
and which can be studied in the future polarized ep
or ee colliders. Here we investigate the QCD twist-3 effects in
to the leading order in QCD.Comment: 4 pages, LaTeX2e, 2 eps figures, ws-ijmpa.cls file included, Talk
given at the 3rd Circum-Pan-Pacific Symposium on High Energy Spin Physics,
Beijing, October 8-13, 2001, to appear in the Proceeding
Solid Phase Synthesis of the Active Center Octapeptide of Candida krusei Cytochrome C Apoprotein
The active center octapeptide of Candida krusei cytochrome C apoprotein, H_2N-Cys-Ala-Glu-Cys-His-Thr-Ile-Glu-OH, was synthesized by the Merrifield method using an automatic peptide synthesizer
Mass effects in the polarized virtual photon structure
We discuss target mass effects in the polarized virtual photon structure
functions , for the kinematic
region , where is the mass squared of
the probe (target) photon. We obtain the expressions for the structure
functions in closed form by inverting the Nachtmann moments for the twist-2 and
twist-3 operators. Numerical analysis shows that target mass effects appear at
large and become sizable near the maximal value of , as the ratio
increases. Target mass effects for the QCD sum rules of
and are also investigated.Comment: 5 pages, LaTeX, 4 eps figures, npb.sty file included, Talk given at
Loops and Legs 2004, Zinnowitz, Germany, April 25-30, 2004, to appear in the
Proceeding
Enhancement of colony forming ability in the lung by transfer of the v-fos oncogene into a ras-transformed rat 3Y1 cell line
AbstractTransfer of the v-fos oncogene into a rat 3Y1 cell line transformed by v-H-ras, which is tumorigenic but non-metastatic, enhanced lung metastasis, depending on the amount of fos-related transcripts. Enhancement of the metastatic potential was associated with increases in tumor growth rate i.m. of inoculated cells but not the rate of in vitro cell growth, irrespective of the addition of tissue (e.g. lung) extract to the regular medium. These results suggest that the v-fos oncogene increased the malignancy by altering biological factors of the recipient cells responsible for cell growth and/or survival rate in vivo
Usefulness of helical computed tomography in diagnosing pulmonary vein stenosis in infants.
We investigated the usefulness of helical computed tomography(CT)in the morphological diagnosis of pulmonary vein stenosis, particularly that in infants and small children. In total, 20 helical CT examinations were performed in 10 post-operative cases of Total Anomalous Pulmonary Venous Drainage(TAPVD), 3 cases of single right ventricle, and 1 case of single left ventricle. In all cases, distinct morphological imaging was possible. Pulmonary vein stenosis could be categorized into three types: (1)stenosis from the anastomosis of the common pulmonary vein (CPV)-the left atrium (LA) to the peripheral pulmonary vein; (2) stenosis only at the anastomosis of CPV-LA; and (3) stenosis due to compression by nearby organs. Coronal views by multiplanar reconstruction (MPR) provided morphological information along the up-down direction of the body axis. Morphological diagnosis of pulmonary vein stenosis is important in deciding prognosis and therapeutic regimens, and helical CT was considered useful for such diagnosis in our 14 young patients.</p
Transition from real to virtual polarized photon structures
We investigate the transition of the polarized photon structure function
when the target photon shifts from on-shell ()
to far off-shell () region. The analysis is performed to the
next-to-leading order in QCD. The first moment of which vanishes
for the real photon, turns to be a negative value when target photon becomes
off-shell. The explicit -dependence of the first moment sum rule as well
as of the structure function as a function of is
studied in the framework of the vector meson dominance model.Comment: 16 pages, 4 eps figure
Virtual photon structure functions and positivity constraints
We study the three positivity constraints among the eight virtual photon
structure functions, derived from the Cauchy-Schwarz inequality and which are
hence model-independent. The photon structure functions obtained from the
simple parton model show quite different behaviors in a massive quark or a
massless quark case, but they satisfy, in both cases, the three positivity
constraints. We then discuss an inequality which holds among the unpolarized
and polarized photon structure functions , and
, in the kinematic region , where is the mass squared of the probe (target) photon, and we examine
whether this inequality is satisfied by the perturbative QCD results.Comment: 24 pages, 13 eps figure
Target Mass Effects in Polarized Virtual Photon Structure Functions
We study target mass effects in the polarized virtual photon structure
functions , in the kinematic
region , where is the mass squared of
the probe (target) photon. We obtain the expressions for and in closed form by inverting the
Nachtmann moments for the twist-2 and twist-3 operators. Numerical analysis
shows that target mass effects appear at large and become sizable near
, the maximal value of , as the ratio
increases. Target mass effects for the sum rules of and
are also discussed.Comment: 24 pages, LaTeX, 9 eps figure
Polarized Photon Structure: and
We investigate the polarized photon structure functions and
which can be studied in the future polarized version of ep or
ee colliders. The NLO QCD calculations of and the possible
twist-3 effects in are discussed.Comment: 8 pages, LaTeX2e, 1 eps figure, cjpsuplf.cls file included, Talk
given at the Advanced Study Institute on Symmetries and Spin,
Praha-SPIN-2001, Prague, July 15-28, 2001, to appear in the Proceeding
Parton distributions in the virtual photon target up to NNLO in QCD
Parton distributions in the virtual photon target are investigated in
perturbative QCD up to the next-to-next-to-leading order (NNLO). In the case
, where () is the mass squared of the
probe (target) photon, parton distributions can be predicted completely up to
the NNLO, but they are factorisation-scheme-dependent. We analyse parton
distributions in two different factorisation schemes, namely and
schemes, and discuss their scheme dependence. We show that
the factorisation-scheme dependence is characterised by the large-
behaviours of quark distributions. Gluon distribution is predicted to be very
small in absolute value except in the small- region.Comment: 28 pages, 5 figures, version to appear in Eur. Phys. J.
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