Self-Rated Mental Health, School Adjustment, and Substance Use in Hard-of-Hearing Adolescents

This survey, “Life and Health—Young People 2005,” included all 15/16-year-old adolescents in mainstream schools in the county of Örebro, Sweden. Just students with a slight/mild or moderate hearing loss were included. There were 56 (1.9%) “hard-of-hearing (HH) students with multiple disabilities,” 93 (3.1%) students who were “just HH,” 282 (9.7%) students with some “other disability than HH,” and 2,488 (85.2%) students with “no disability.” “HH with multiple disabilities” reported considerably higher scores for mental symptoms, substance use, and school problems than the “no disability” group. Those with “just HH” and those with “other disability than HH” had more mental symptoms and school problems than the “no disability” group but no significant differences in substance use. In conclusion, the combination of a hearing loss and some other disability strongly increases the risk for mental symptoms, school problems, and substance use. This group, thus, is an important target for preventive measures

Shape coexistence at the proton drip-line: First identification of excited states in 180Pb

Excited states in the extremely neutron-deficient nucleus, 180Pb, have been identified for the first time using the JUROGAM II array in conjunction with the RITU recoil separator at the Accelerator Laboratory of the University of Jyvaskyla. This study lies at the limit of what is presently achievable with in-beam spectroscopy, with an estimated cross-section of only 10 nb for the 92Mo(90Zr,2n)180Pb reaction. A continuation of the trend observed in 182Pb and 184Pb is seen, where the prolate minimum continues to rise beyond the N=104 mid-shell with respect to the spherical ground state. Beyond mean-field calculations are in reasonable correspondence with the trends deduced from experiment.Comment: 5 pages, 4 figures, submitted to Phys.Rev.

First observation of excited states in 173Hg

The neutron-deficient nucleus 173Hg has been studied following fusion-evaporation reactions. The observation of gamma rays decaying from excited states are reported for the first time and a tentative level scheme is proposed. The proposed level scheme is discussed within the context of the systematics of neighbouring neutron-deficient Hg nuclei. In addition to the gamma-ray spectroscopy, the alpha decay of this nucleus has been measured yielding superior precision to earlier measurements.Comment: 5 pages, 4 figure

Further studies on relic neutrino asymmetry generation I: the adiabatic Boltzmann limit, non-adiabatic evolution, and the classical harmonic oscillator analogue of the quantum kinetic equations

We demonstrate that the relic neutrino asymmetry evolution equation derived from the quantum kinetic equations (QKEs) reduces to the Boltzmann limit that is dependent only on the instantaneous neutrino number densities, in the adiabatic limit in conjunction with sufficient damping. An original physical and/or geometrical interpretation of the adiabatic approximation is given, which serves as a convenient visual aid to understanding the sharply contrasting resonance behaviours exhibited by the neutrino ensemble in opposing collision regimes. We also present a classical analogue for the evolution of the difference in $\nu_{\alpha}$ and $\nu_s$ number densities which, in the Boltzmann limit, is akin to the behaviour of the generic reaction $A \rightleftharpoons B$ with equal forward and reverse reaction rate constants. A new characteristic quantity, the matter and collision-affected mixing angle of the neutrino ensemble, is identified here for the first time. The role of collisions is revealed to be twofold: (i) to wipe out the inherent oscillations, and (ii) to equilibrate the $\nu_{\alpha}$ and $\nu_s$ number densities in the long run. Studies on non-adiabatic evolution and its possible relation to rapid oscillations in lepton number generation also feature, with the introduction of an adiabaticity parameter for collision-affected oscillations.Comment: RevTeX, 38 pages including 8 embedded figure

The Increase in the Primordial He-4 Yield in the Two-Doublet Four-Neutrino Mixing Scheme

We assess the effects on Big Bang Nucleosynthesis (BBN) of lepton number generation in the early universe resulting from the two-doublet four-neutrino mass/mixing scheme. It has been argued that this neutrino mass/mixing arrangement gives the most viable fit to the existing data. We study full 4 x 4 mixing matrices and show how possible symmetries in these can affect the BBN He-4 abundance yields. Though there is as yet no consensus on the reliability of BBN calculations with neutrino flavor mixing, we show that, in the case where the sign of the lepton number asymmetry is unpredictable, BBN considerations may pick out specific relationships between mixing angles. In particular, reconciling the observed light element abundances with a \bar\nu_\mu \bar\nu_e oscillation interpretation of LSND would allow unique new constraints on the neutrino mixing angles in this model.Comment: 12 pages, including 4 figures, to appear in Phys. Rev.

In-beam spectroscopic study of 244Cf

The ground-state rotational band of the neutron-deficient californium (Z = 98) isotope 244Cf was identified for the first time and measured up to a tentative spin and parity of I = 20+. The observation of the rotational band indicates that the nucleus is deformed. The kinematic and dynamic moments of inertia were deduced from the measured gamma-ray transition energies. The behavior of the dynamic moment of inertia revealed an up-bend due to a possible alignment of coupled nucleons in high-j orbitals starting at a rotational frequency of about hw = 0.20 MeV. The results were compared with the systematic behavior of the even-even N = 146 isotones as well as with available theoretical calculations that have been performed for nuclei in the region

In-beam spectroscopic study of Cf-244

The ground-state rotational band of the neutron-deficient californium (Z = 98) isotope 244Cf was identified for the first time and measured up to a tentative spin and parity of I I-pi = 20(+). The observation of the rotational band indicates that the nucleus is deformed. The kinematic and dynamic moments of inertia were deduced from the measured gamma-ray transition energies. The behavior of the dynamic moment of inertia revealed an up-bend due to a possible alignment of coupled nucleons in high-j orbitals starting at a rotational frequency of about (h) over bar (omega) = 0.20 MeV. The results were compared with the systematic behavior of the even-even N = 146 isotones as well as with available theoretical calculations that have been performed for nuclei in the region.Peer reviewe