[en] The aim of our investigations is to investigate the possibility of using the measurement of high energetic delta-electrons for a spectroscopy of superheavy quasiatoms. We find indeed that by this way the binding energies of electrons in superheavy systems can be experimentally determinated to some extend. This supplements the spectroscopy of superheavy quasimolecules through measurement of the frequency and angular distribution of quasimolecular radiation and through the measurement of the impact parameter dependence of ionization. The latter can be determined by the measurement of the asymptotic Ksub(α)-radiation in coincidence with the impact parameter b. (author)

No abstract available

[en] The rate of aquation of bromopentaammine cobalt(III) ion in the presence of different types of dicarboxylate solutions containing tert-butanol (40% V/V) have been measured spectrophotometrically at different temperatures (30-600⁰C) in the light of the effects of ion-pairing on reaction rates and mechanism. The thermodynamic and extrathermodynamic parameters of activation have been calculated and discussed in terms of solvent effect on the ion-pair aquation reaction. The free energy of activation ΔG_ip* is more or less linearly varied among the studied dicarboxylate ion-pairing ligands indicating the presence of compensation effect between ΔH_ip* and ΔS_ip*. Comparing the kip values with respect of different buffers at 40% of ter-butanol is introduced. (author)

No abstract available

[en] Mouse models have informed us that p63 is critical for normal epidermal development and homeostasis. The p53/p63/p73 family is expressed as multiple protein isoforms due to a combination of alternative promoter usage and C-terminal alternative splicing. These isoforms can mimic or interfere with one another, and their balance ultimately determines biological outcome in a context-dependent manner. While not frequently mutated, p63, and in particular theΔNp63 subclass, is commonly over expressed in human squamous cell cancers. In vitro keratinocytes and murine transgenic and transplantation models have been invaluable in elucidating the contribution of altered p63 levels to cancer development, and studies have identified the roles forΔNp63 isoforms in keratinocyte survival and malignant progression, likely due in part to their transcriptional regulatory function. These findings can be extended to human cancers; for example, the novel recognition of NFκB/c-Rel as a downstream effector of p63 has identified a role for NFκB/c-Rel in human squamous cell cancers. These models will be critical in enhancing the understanding of the specific molecular mechanisms of cancer development and progression.

[en] Theoretical results for the delta-electron distribution and positron emission in superheavy systems are compared with recent experimental data. Special emphasis is laid on atomic excitations in deep inelastic nuclear collisions. It is demonstrated that the study of heavy-ion collisions with nuclear time delay promises clear signature for the spontaneous positron emission. Corresponding experimental results show evidence for this transition from the neutral vacuum to a charged ground state and for the existence of long living nuclear molecules. (orig.)

[en] Linear energy transfer, L, is currently used as reference parameter for the quality factor in radiation protection, and this practice is likely to be continued in an impending revision of the quality factor. But the numerical convention is not, at present, actually applied to photon or electron fields; their quality factor is, instead, summarily equated to unity. The current trend of tightened dose limits in radiation protection may create the need for precise computations of quality factors even for photon and electron radiations. Such computations can, however, not be performed in terms of unrestricted linear energy transfer. The reasons for this difficulty are explained, and the formulae for the quality factor as an integral over electron fluence and restricted linear energy transfer are given. A correct energy balance in this and in a variety of linked dosimetric relations requires a modification of the definition of restricted linear energy transfer. For large energy cut-off values the correction is of minor importance, but for small cut-off values - such as those invoked in biophysical considerations - the modification is essential. (author)

[en] A completely functional multiwire proportional counter (MWPC) for measuring energy-deposition was designed, built, tested, and evaluated. The MWPC was specifically designed for application to the determination of the role of secondary particles in the ionization process. It is particularly useful for studies of their part in the energy deposition taking place in small volumes of biologic interest surrounding the tracks of charged particles. This is the first instrument to be used for the measurement of energy deposition rather than to the determination of the path of the primary. Experiments were approved for use of the Bevalac and have used the MWPC successfully at this installation. A second generation counter employing such features as variable wire spacing, variable plane spacing, and variable volume in a direction perpendicular to the wire planes was designed and built. These changes will allow use of the maximum gas gain in all operating pressures and allow better definition of the sensitive volume

No abstract available

[en] The nonrelativistic problem of the scattering of two dyons (including the case of electron scattering by magnetic monopoles) is systematically studied, both classically and quantum mechanically, with a view toward the discrimination between various combinations of electric and magnetic charges. The classical cross section is analyzed with particular attention to the interesting phenomena which occur for large angle scattering, the ''rainbows'' and ''glory,'' where the cross section becomes infinite. Quantum mechanically, it is found that these infinities do not occur and that, when the partial wave scattering amplitude is summed, a very elaborate sturcture emerges for the cross section, which depends sensitively upon the electric and magnetic charges of the particles, as well as on their relative speed. A large modification is discussed, leading to spin flip and nonflip amplitudes, due to the dipole moments of the particles. Numerical results are presented for a variety of values of these parameters. In principle, these results could be used to distinguish the delta-ray distributions produced by the various species of electrically and magnetically charged particles. Quite apart from the experimental implications of our numerical results, a number of theoretical improvements and extensions have been made. Numbered among these are the consideration of dyons and particles having dipole moments, and the explicit demonstration, based on the methods of angular momentum, that the differential cross section is independent of the choice of singularity line