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Notes: Summary. The distribution, morphology and antigen expression of endometrial glands, uterine vessels and fetal trophoblast have been studied in third trimester placental bed tissues with a panel of monoclonal antibodies in immunohistochemical techniques. Residual endometrial glands were numerous but often were attenuated or compressed and could only be identified clearly with epithelial cell markers. These glands must be clearly distinguished from vessels and trophoblast in immunological studies of cells in the placental bed. The changing pattern of antigen expression of both maternal glands and fetal trophoblast in placental bed tissues may indicate a form of local regulation of gene expression.

Notes: Summary. A novel protocol is described which has been developed for immunotherapy in unexplained recurrent miscarriage. This is based on a single intravenous infusion with isolated placental trophoblast plasma membrane vesicle preparations. Clinical experience gained with this approach is described. A total of 16/21 (76%) patients who subsequently had pregnancies have now achieved a live birth or are currently pregnant at greater than 28 weeks gestation.

Notes: The incidence of thrombocythaemia (a platelet count 〉600×l09/l) in a 10-year survey was 7 per 106 population per year (R. M. Pettit, personal communication). It is generally a disease of late middle age, but a second population of young and mainly female patients has been described (Hoagland & Silverstein 1978). An increased platelet count can be secondary (after splenec-tomy, associated with inflammation, malignancy or iron deficiency) or due to a primary myeloproliferative disorder. We describe four patients in whom a series of miscarriages before 20 weeks gestation appears associated with thrombocythaemia and estimate the prevalence of this association in patients with unexplained repeated miscarriage.

Notes: A series of experiments was performed with an Applied-B ion diode on the Particle Beam Fusion Accelerator-I, with peak voltage, current, and power of approximately 1.8 MV, 6 MA, and 6 TW, respectively. The purpose of these experiments was to explore issues of scaling of Applied-B diode operation from the sub-TW level on single module accelerators to the multi-TW level on a low impedance, self-magnetically insulated, multimodule accelerator. This is an essential step in the development of the 100-TW level light ion beam driver required for inertial confinement fusion. The accelerator and the diode are viewed as a whole because the power pulse delivered by the 36 imperfectly synchronized magnetically insulated transmission lines to the single diode affects module addition, diode operation, and ion beam focusability. We studied electrical coupling between the accelerator and the diode, power flow symmetry, the ionic composition of the beam, and the focusability of the proton component of the beam. Scaling of the diode impedance behavior and beam quality with electrical drive power is obtained from comparison with lower-power experiments.The diode impedance lifetime was about 10 ns, several times shorter than for lower-power experiments. Azimuthal and top-to-bottom variations of the diode and ion currents were found to be approximately ±10%, compared with an estimated requirement of 5%–7% uniformity to avoid focal blurring by self-magnetic field effects. The ion production efficiency was 80%–90%. However, only 50%±10% of the ion current was carried by protons; the balance was carried by multiply charged carbon and oxygen ions. Activation measurements showed a proton beam energy of approximately 50 kJ. A gas cell filled with 5 Torr of argon was used for beam transport. The macroscopic divergence was 15±10 mrad and the microscopic divergence was 20±15 mrad, values that are similar to those from lower-power experiments. A model of beam focusing is formulated that predicts the proton charge focused onto 0.47-cm radius lithium targets, taking into account beam purity, magnetic bending, small-angle multiple scattering, and intrinsic divergence. The model results and activation measurements of the number of protons focused onto targets agree, and indicate that the spatially averaged (over about 3 cm2) peak focal power was about 0.5 TW/cm.2 The most important limitations on power concentration were found to be the low proton content of the beam, the short impedance lifetime of the diode, and the asymmetric current feed of the accelerator. The short impedance lifetime limited the power coupled to the diode, and caused the voltage at peak ion power to be low, which exacerbates the small-angle scattering problem. The asymmetric feed caused focal blurring through nonuniform self-magnetic bending. At least partly because of the experience gained with low impedance beams during these experiments, the next generation accelerator, the 100-TW Particle Beam Fusion Accelerator-II, has been configured to produce a 25–30-MV Li+ beam rather than a 5-MV proton beam. off

Notes: The mass analyzed threshold ionization spectra of trans-2-butene and propene have been obtained using single-step vacuum ultraviolet excitation. The ionization potential for trans-2-butene is 73 605±4 cm−1, while for propene it is 78 587±4 cm−1. Both species have progressions of the low frequency, torsional, normal modes. Using the torsional normal mode and first overtone from a trans-2-butene cation the torsional barrier is determined to be approximately 453 cm−1, assuming a sinusoidal potential. Normal mode analysis indicates that all low frequency normal modes of the propene cation involve substantial internal motion of the vinyl component, and the spectrum shows a very anharmonic torsional mode progression. These factors complicate direct torsional barrier analysis from the experimental lines, but through the use of various ab initio methods the propene torsional barrier is determined to be approximately 429 cm−1. Due to the anharmonicity found in propene, the correlation corrected vibrational self-consistent field method in GAMESS was used to verify the assignments of the experimental lines. The torsional barriers for both cations are found to lie approximately 275–300 cm−1 below the barrier heights of the neutral species. © 2001 American Institute of Physics.

Notes: A pulsed electric discharge in a pulsed supersonic jet of N2 is found to produce high densities of metastable E3Σ+gN2. Subsequent laser irradiation of these metastables results in single-photon excitation to autoionizing states. Singly charged cations are detected by time-of-flight mass spectrometry or alternatively, ejected electrons are detected by TOF electron energy analysis. From both the laser excitation spectra and photoelectron spectra we have identified a number of autoionizing Rydberg states, including a triplet Rydberg series (np=8−26) 3Πu←E 3Σ+g converging to the ground state ion, the first member of an s-type triplet Rydberg series 3Σ+u←E converging to the B state of the ion and the lowest member of a d-type triplet Rydberg series 3Πu and 3Σ+u←E converging to the A state of the ion. Some of these transitions involve core excitations of a 3s Rydberg state configuration, resulting in a doubly excited electronic configuration [He(2sσg)2(2sσu)(2pπu)4 (2pσg)2(3sσg)]. Other transitions confirm that the E state is a mixture of a 3s Rydberg state with an X ionic core and a 3p Rydberg state with an A ionic core.

Notes: A differential optical reflectivity measurement technique for freestanding films is presented. The system is highly sensitive to changes in the polarization state of the reflected light. The method is used to study the evolution of an optically anisotropic liquid crystalline structure with temperature. In addition we present a reflectivity method for determining the film thickness for films consisting of two to hundreds of layers. © 2000 American Institute of Physics.

Notes: The plasma equation for a warm collisionless plasma with a Maxwellian particle source is solved in plane parallel geometry. The generalized Bohm criterion is used to identify the plasma–sheath boundary. This kinetic treatment, in common with fluid and cold-ion kinetic models, results in an infinite electric field at the sheath edge. This is in sharp contrast to results from a previous warm-ion kinetic model, by Emmert et al. [Phys. Fluids 23, 803 (1980)], which gave a finite electric field at the sheath edge. Also, the presheath potential given by the present model is greater than that given by Emmert and is in better agreement with fluid results.