We present the results of a calculation, based on the absorption model with U(6,6) symmetry imposed at the peripheral vertices, of the reaction $p+\overline{p}\to n+\overline{n}$ at 3.0, 3.6, 5.0, 6.0, 7.0, and 9.0 GeV/c. Agreement within the experimental errors is obtained at all energies for $-t<~0.6$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$. At larger momentum transfers there are discrepancies as expected for a peripheral-type model.

The absence of a characteristic length at the lambda temperature $T_{\lambda }$ of liquid helium is used to determine the wave-number dependence of the phase fluctuations and the second-sound dispersion relation $\omega =a{k}^{\frac{3}{2}}$ where $\omega$ and $\overrightarrow{\mathrm{k}}$ are the frequency and wave number and $a\approx 0.1 {\mathrm{cm}}^{\frac{3}{2}}$ ${\sec }^{-1\mathrm{}}$. Further predictions are ${|T-T_{\lambda }|}^{-\frac{1}{3}}$ singular temperature variation for second-sound damping ($T<\mathrm{}{T}_{\lambda }$) and the thermal conductivity ($T>\mathrm{}{T}_{\lambda }$).

An apparatus for the use of nuclear adiabatic demagnetization has now produced and maintained submillidegree temperatures for as long as seven hours. It has cooled 0.45 ${\mathrm{cm}}^3$ of ${\mathrm{He}}^3$ at various pressures to 4 mdeg K in the liquid state and to approximately 7 mdeg K in the solid state. Measurements of the nuclear-spin susceptibility, specific heat, and thermal-boundary impedance have been made to these temperatures in the liquid and some preliminary observations made in the solid.

Th-Gd alloys show a full Meissner effect and magnetization curves which are reversible to 0.6% of $H_c$. Critical field curves agree with the Abrikosov-Gor'kov theory to an accuracy of about 3%.

A beam of polarized deuterons has been scattered from a helium target. The results show that $d-\alpha$ scattering is a useful analyzer for deuteron vector polarization for most deuteron energies between 2.5 and 10 MeV. It is also observed that the $d-\alpha$ break-up reaction is strongly dependent on deuteron spin.

Partial symmetry is proposed as the general basis for a phenomenological method that replaces current algebra. Its practical merit is displayed through a reinterpretation of combined internal and spin transformations. Among various results referring to coupling constants, magnetic moments, and electromagnetic decays, the following is noted: $-\frac{G_A}{G_V}=2^{-\frac{1}{2}}\times \frac{5}{3}=\mathrm{1.18.}\mathrm{}$

Cross sections for the reaction $\gamma +p\to {\pi }^0+p$ for incident gamma-ray energies of 2.0 to 5.0 GeV and for baryon four-momentum transfers squared of 0.5 to 4.0 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ are presented. The results are compared with theoretical predictions based on Reggeized vector-meson exchange.