Search

We have measured the beam-normal single-spin asymmetry An in the elastic scattering of 1-3 GeV transversely polarized electrons from 1H and for the first time from 4He, 12C, and 208Pb. For 1H, 4He, and 12C, the measurements are in agreement with calculations that relate An to the imaginary part of the two-photon exchange amplitude including inelastic intermediate states. Surprisingly, the 208Pb result is significantly smaller than the corresponding prediction using the same formalism. These results suggest that a systematic set of new An measurements might emerge as a new and sensitive probe of the structure of heavy nuclei [ABSTRACT FROM AUTHOR]

We present a search at the Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α' to electrons. Such a particle A' can be produced in electron-nucleus fixed-target scattering and then decay to an e+ e- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175-250 MeV, found no evidence for an A' → e+e- reaction, and set an upper limit of α'/α ≃ 10-6. Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces. [ABSTRACT FROM AUTHOR]

Aim. This histochemical and immunohistochemical study was aimed at examining the brain cellular structures of newborn rats exposed to prenatal immobilization (IMO) stress. Methods. Histochemical method on detection of Ca2+-dependent acid phosphatase activity and ABC immunohistochemical technique. Results. Cell structures with radial astrocytes marker GFAP, neuroepithelial stem cell marker gene nestin, stem-cells marker and the hypothalamic neuroprotective proline-rich polypeptide PRP-1 (aka Galarmin, a natural cytokine of a common precursor to neurophysin vasopressin associated glycoprotein) have been revealed in several brain regions. Conclusions. Our findings indicate the process of generation of new neurons in response to IMO and PRP-1 involvement in this recovery mechanism, as PRP-1-Ir was detected in the above mentioned cell structures, as well as in the neurons and nerve fibers. [ABSTRACT FROM AUTHOR]