[en] An explanation is proposed for the observation of giant haloes in biotites. These haloes can be attributed to the α-decay of common unstable natural isotopes from excited nuclear states. (Auth.)

[en] The authors apply the method derived in a previous paper to Field's equations governing the behaviour of the interstellar medium, including the radiation field, and to Schatzman's equations governing the behaviour of a slab of hydrogen gas ionized and heated by a flux of photons coming from both sides. (Auth.)

[en] After a general introduction, extracts are presented from early sources which deal directly with heliacal phases. These extracts describe heliacal risings and settings of the stars, heliacal risings and settings of the five planets, the MF and EL of stars under the rays of the sun and heliacal risings and settings of the luminaries. (C.F.)

[en] During the second phase of the evolution of the universe, which lasted from 10^-4 to 10 seconds after the big bang, the particle collisions were determined by the weak interaction. The frequency of these collisions was high enough so as to allow for a statistical description. In the present theory a Boltzmann-type kinetic theory is employed, which has relativistic as well as quantum character. On its basis and using the neutral current part of the weak interaction it turns out that expressions can be obtained for the transport coeffients. Numerical values are then found for the viscosity and the heat conductivity-crucial parameters in cosmology-crucial parameters in cosmology-of a neutrino gas. (Auth.)

[en] The relativistic quantum transport equation is discussed. From the linearized theory the transport coefficients are found in terms of the particle interaction. (Auth.)

[en] The author has correlated the average winter temperature in Holland for the years 1634 - 1975 with the maximum sunspot number for solar cycles and shows that each there is some correlation for each 11-years cycle. (Auth.)

[en] Oligothymidine strands form a parallel duplex based on thymine-thymine base pairs after methylation of the phosphate groups. A similar duplex can be obtained by shielding of the phosphate charges with the polycationic protein poly-L-lysine, as determined earlier with UV hyperchromicity experiments. ¹H and ³¹P NMR studies are presented on the model system d(T₁₀)/Lys₁₈ that corroborate this model. Binding of the protein to the phosphate groups of the DNA was ascertained from an upfield shift in the ³¹P spectrum. The presence of a DNA duplex structure was deduced from an imino chemical shift of 13.0 ppm, which indicates thymine-thymine base pairing. With variable temperature ³¹P studies, a melting temperature of 30⁰C was found in water, agreeing with UV hyperchromicity experiments. Preliminary NOESY measurements show a right-handed helix structure for the DNA, and several DNA-protein NOEs have been established. The experimental data are in agreement with a triple-stranded DNA/protein helix with frayed ends. Based on this model, a molecular modelling study was performed to predict the protein conformation that accommodates a parallel DNA duplex. 11 refs.; 3 figs.; 2 tabs

[en] The perturbation theory of Heisenberg picture operators in terms of in-picture fields is presented in the Schwinger formulation. The theory is combined with Bogoliubov's initial condition of vanishing correlations in the infinite past to rederive Keldysh's perturbation scheme for non-equilibrium statistical green functions. (Auth.)

[en] It seems certain now that neutrinos possess a small mass. This means that gases of neutrinos possess the relativistic transport property of volume viscosity, a quantity which vanishes for systems of massless particles. In this review it is outlined how from the linearized relativistic transport equation and the weak interaction Lagrangian one may obtain the values for the transport properties. Special attention is paid to the volume viscosity of simple systems of massive neutrinos. The other transport properties both in simple systems and mixtures of neutrinos and antineutrinos turn out to be affected by the mass in a way negligible under the circumstances of physical or astronomical interest. (Auth.)

[en] This paper continues to report the Dutch expedition to Atar, Mauritania, to observe the total solar eclipse of June 30, 1973. The purpose of this expedition was to obtain spectra from the transition region photosphere-chromosphere with high spectral and time resolution. (Auth.)