Adjuvant effect of Bordetella pertussis vaccine to sheep erythrocytes in mice: enhancement of cell-mediated immunity by subcutaneous administration of adjuvant and antigen

The subcutaneous route (s.c.) was used to study the adjuvant effect of Bordetella pertussis vaccine (PV) on cell-mediated immunity to sheep erythorcytes (SRBC). The immune response was measured by a sensitive assay procedure in which the antigen is injected intracutaneously into the mouse ear and the inflammatory swelling is measured with calipers. PV significantly enhanced cell-mediated immunity to SRBC, and the enhancement persisted for at least 3 weeks. PV administered up to 6 days before SRBC also significantly enhanced the response; PV injected 1 or more days after SRBC was not effective. In addition, it was found that PV per se released into the suspension medium a cell-free component(s) (pertussis supernatant) that contributed significantly to adjuvanticity. The adjuvanticity of both PV and PS was completely eliminated by heat.     

Chemical heterogeneity of coal

The solvent and other types of extractions of Vahrman, which have produced a surprisingly large yield of ‘small molecules’, are considered in the light of the results of flash heating of coal. It is suggested that the products of flash heating represent relatively unchanged small molecules which have been discharged so rapidly from the heated coal particle that they have undergone very little chemical rearrangement. On this assumption, flash-heating experiments support the postulates of Vahrman.     

A new technique for measuring velopharyngeal orifice area during sustained vowel production: an application of aerodynamic forced oscillation principles

A new technique for measuring velopharyngeal orifice area during sustained vowel production is described. The technique is based on a simple oscillatory flow balancing procedure between two aerodynamic branches, a mechanical model of the human upper airway and the subject's upper airway. The area of the velopharyngeal orifice in the model is adjusted until identical oscillatory flows traverse it and the subject's velopharyngeal orifice in response to a common forced oscillatory pressure. When identical oscillatory flows are observed, the area of the adjusted orifice is taken as a measure of the area of the subject's velopharyngeal orifice.     

Coupling Errors in Ground Vehicle Communication Systems

Communication systems for high-speed ground vehicles which employ coupled surface waveguides are considered in this paper. We determine communication errors resulting from AM and FM transmission for the coupling configuration of two randomly separated Goubau lines as a function of the various system parameters. Results are given which indicate that filtering of the transmitted and received signals leads to enhanced communications.     

Editorial: Open Source and Empirical Software Engineering

Editorial Commentary

Editorial: Open Source and Empirical Software Engineering     

Capacitive transducers with curved electrodes

The design, performance, and potential applications are described for capacitive transducers with curved electrodes. A curved electrode governs the deflection of a compliant electrode under applied stress. A dielectric film on one electrode provides a variable region of fixed electrode spacing. The sensitivity and linear dynamic range of the transducers are higher and wider than devices with parallel electrodes. An electrical advantage is obtained from the permittivity of the dielectric film and a mechanical advantage from its thinness. Transducers have been constructed with silicon diaphragms that bend and polymer membranes that stretch in response to uniform pressure. The silicon sensors measured dynamic pressure changes over a linear range of 125 dB. An 885% change in capacitance was obtained for a sensor with a thin silicon diaphragm. Sensors with polycarbonate membranes demonstrated the ability of a low-cost transducer to measure pressure, fluid flow, displacement, and tilt. An active capacitive bridge circuit was developed to linearly measure capacitance changes up to 1000% and to control electrostatic actuators by force-balanced feedback. Methods and materials to construct microscale transducers are discussed along with the performance limitations of electrostatic actuation.