Prospects for HERMES Run II

Data taking for Run II of the HERMES experiment will start in late 2001 with three main physics objectives for the next 4-5 years: a measurement of transversity distributions, an improved measurement of helicity distributions, and measurements of exclusive reactions to access Generalized Parton Distributions.Comment: 8 pages, 5 figures, subm. to Proc. of DIS01, Bologna, Ital

Single Spin Asymmetries in Proton-Proton and Proton-Neutron Scattering at 820 GeV

The physics case is summarised for the investigation of high energy spin phenomena by placing an internal polarised target into HERA's unpolarised proton beam. The luminosity and experimental sensitivity are discussed. Estimating the physics reach of single spin asymmetries in different final states reveals a considerable physics potential in testing the spin sector of perturbative QCD.Comment: 10 pages + 5 uuencoded ps figures, late

DIS structure functions and the double-spin asymmetry in rho(0) electroproduction within a Regge approach

The proton, neutron and deuteron structure functions F2(x,Q2) and g1(x,Q2), measured at intermediate Q2, are analyzed within a Regge approach. This analysis serves to fix the parameters of this scheme which are then used to calculate, in a unified Regge approach, the properties of ρ0 meson electroproduction on the proton and the deuteron. In this way, the double-spin asymmetry observed at HERMES in ρ0 electroproduction on the proton, can be related to the anomalous behavior of the flavor-singlet part of the spin-dependent structure function g1(x,Q2) at small x

European Perspectives for Electron-Nucleon Scattering at the Luminosity Frontier

European perspectives are discussed on fixed-target electron or positron scattering experiments using polarized and unpolarized beams and targets in various combinations. The goal envisioned is a deep and complete understanding of the momentum and spin structure of hadrons in the context of Quantum Chromo Dynamics, based on measurements at moderate and low photon virtualities. This program can be realized by performing electron-nucleon experiments with high resolution and high luminosity, at beam energies of at least 25-30 GeV.Comment: 7 pages, 6 figures, Invited talk at the Workshop `The Spin Structure of the Proton and Polarized Collider Physics', Trento/Italy, July 23-28, 2001; to appear in Nuclear Physics B (proc suppl

Molecular analysis of desmoid tumors with a high-density single-nucleotide polymorphism array identifies new molecular candidate lesions

Background: Desmoid tumors are neoplastic proliferations of connective tissues. The mutation status of the gene coding for catenin (cadherin-associated protein) beta 1 (CTNNB1) and trisomy 8 on the chromosomal level have been described to have prognostic relevance. Patients and Methods: In order to elucidate new molecular mechanisms underlying these tumors, we carried out a molecular analysis with a genome-wide human high-density single-nucleotide polymorphism (SNP) array, in 9 patients. Results: Single samples showed numerical aberrations on chromosomes (Chrs) 20 and 6 with either trisomy 20 or monosomy 6. No trisomy 8 could be detected. Recurrent heterozygous deletions were found in Chr 5q (including the APC gene locus, n = 3) and Chr 8p23 (n = 4, containing coding regions for the potential tumor suppressor gene CSMD1). This novel deletion in 8p23 showed an association with local recurrence. In addition, structural chromosomal changes (gain of Chrs 8 and 20) were found in a minority of cases. Conclusion: The genomic alteration affecting the candidate gene CSMD1 could be important in the development of desmoid tumors