A Microcomputer-Based Differential Lung Ventilation System

In order to provide a versatile means of delivering differential lung ventilation (DLV), a computer-controlled system was constructed to allow a variety of ventilation protocols as well as to record and monitor relevant physiologic parameters. Two Siemens servo ventilators were modified for synchronous operation and computer control of minute volume and respiratory rate. Twenty-five parameters on the two lungs were collected every breath. Feedback control was used to adjust respiratory rate to maintain PaCO2 = 35 torr and to keep total tidal volume equal to 15 mI/kg. Three differential volume delivery protocols were established. The DLV system was evaluated in a study involving eighteen mongrel dogs (six dogs for each volume delivery protocol), each with a unilateral lung injury caused by an infusion of 0.1 N HOC through the endobronchial tube. This system has proven to be a highly effective and versatile means of providing differential ventilation as well as precise feedback control of essential physiologic parameters such as PaCO2 and tidal volume. The system handles automated data collection of all relevant physiological parameters, making graphical as well as statistical analysis extremely easy.     

Bifurcation theory and order of phase transition for proximity effect sandwiches

We use bifurcation theory to study the order of the phase transition for inhomogeneous superconducting systems described by the Ginzburg-Landau equations. Complete qualitative information on the behavior near the critical point can be obtained using these techniques of nonlinear analysis and the calculus of variations. We prove in a rigorous way that there is a secondorder phase transition for a normal-superconducting-normal (N-S-N) proximity sandwich. Moreover, in the case of a magnetic-superconductingmagnetic (M-S-M) proximity sandwich we show the dependence of the order of the phase transition on the coupling constant between the magnetic and superconducting order parameters.Partially supported by CNR-GNSM.     

Oral communication and sales effectiveness.

The relationship between oral communication and sales effectiveness was investigated. 2 equatable groups of working sales people, a more effective "high" group and a less effective "low" group, were compared in terms of selected aspects of their communication behavior. Findings indicated that evaluations of basic oral communication skill (including listening) reliably differentiated between the 2 groups. Sales methods such as using "emotional appeals" and "dramatizing" also distinguished between the more effective and the less effective sales people. Results suggested: that evaluations of basic oral communication skill by a trained interviewer should be one valuable indicator of sales success; that communication training programs should subordinate fragmental, relatively isolated details of communication behavior to consideration of generalized communication skill; and that sales people who are inferior in basic oral communication skill will also be less effective in utilizing specialized persuasive techniques. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A frequency stabilized compact high repetition rate TEA-CO2laser

A compact atmospheric-pressure hybrid CO2laser utilizing a transverse double-discharge technique has been constructed and operated at moderate repetition rates. A pulse output energy of 80 mJ has been obtained under single-mode conditions at repetition frequencies of 100 Hz. Using the hybrid technique to obtain single-longitudinal-mode operation, we have been able to reach a 7 kHz long-term relative frequency instability between the TEA laser and a local oscillator. Measurements of the frequency sweeping during the pulse tail (chirp) are also presented along with a direct measurement of the resonant frequency pulling effect associated with the real part of the electric susceptibility of the gas. Limitations on the pulse repetition frequency for this laser configuration are also discussed.     

Photodegradable polyethylene

Polymer photodegradation can be achieved by introducing carbonyl groups which absorb radiations above the 300 mμ wavelength and thus are sensitized by solar or atmospheric radiations. We introduced these groups in polyethylene by oximation of aliphatic chain with photoactivated NOCI and hydrolysis of the oxime. Modified polymers show, during accelerated aging in Weather-O-Meter, a constant molecular weight decrease, which is directly proportional to the concentration of carbonyl groups.     

Detection and assay of single cell protein products in blends with animal feeds.

Electrophoretic patterns of protein extracts obtained with different procedures from the BP-yeast product named Toprina (a Candida lipolytica strain grown on n-alkanes) have been compared with protein electrophoretic patterns of a number of different microbial species. The gel electrophoretic pattern of the 0.15 M NaCl extract from Toprina was specific enough to allow an easy differentiation of Toprina from the other microorganisms tested. To detect and assay Toprina in blends with animal feeds, an immune serum containing antibodies reacting specifically with Toprina has been prepared by immunising rabbits with an antigen preparation extracted from Toprina with 0.15 M NaCl and precipitated by salting out the extract at 4.0 M (NH₄)₂SO₄. Three main antibodies reacting with Toprina antigens have been found in the anti-Toprina immune serum, but only one was specific of Toprina. The resistance of the Toprina antigens to peptic digestion and their behaviour on extraction, electrophoresis and gel filtration suggest that they might be acidic polysaccharide in nature. Immunodiffusion analyses with the anti-Toprina immune serum of extracts obtained with 0.15 M NaCl from very heterogeneous animal feeds added with different amounts of Toprina, allowed the detection of a Toprina amount as low as 2.5%. An accurate assay of Toprina was achieved by submitting the feed extract to radial immunodiffusion with the anti-Toprina immune serum.