Changes In Potential Distribution Research Articles

Aging in the AXC/SSh rat: Characterization of moderately abundant ventral prostate proteins showing age-dependent diminution and one protein exhibiting age-invariant content

To determine whether prior demonstrations of age-related decrements in prostate content of minor, androgen regulated proteins represent a generalized phenomenon, we validated a denaturing polyacrylamide gel electrophoretic protocol for separation and quantification of moderately abundant ventral prostate cytoplasmic proteins. We established age-related, progressive 3- to 3.5-fold decreases in prostate content of proteins of 90, 79, 63, and 58 kDa and found that content of a 46 kDa protein was age-invariant. The amount of 90 and 46 kDa proteins was not significantly altered, whereas the level of 79, 63 and 58 kDa proteins decreased during 72 h post-orchiectomy of 3-month-old rats. Testosterone injection of intact 26-month-old rats caused an average 2-fold increase in 90, 79, 63, and 58 kDa protein content and did not affect 46 kDa protein level. Because we demonstrated the 46 kDa protein is not a secretory protein, absence of an affect of aging or testosterone on prostate content is not due to secretion mediated inaccessibility to intracellular processing. The apparent relation between age and prostate content of these proteins is not a consequence of potential age-related changes in ventral prostate cell content or distribution because biochemical and histologic analyses show this does not significantly occur. Our studies establish age-related decreases in ventral prostate content of moderately abundant, androgen responsive proteins and show that content of at least one protein is age- and androgen-independent. It remains to be determined whether these findings reflect direct effects of gene regulation.

Design optimization of tall tubular lead/acid cells based on an analysis of the reaction distribution

In order to estimate the discharge performance of tall lead/acid cells (with tubular positives), changes in current and potential distributions with discharge progress were calculated with a computer on the basis of plate resistance and the current—potential—time relationship between small facing parts of positive and negative plates. The taller the cell, the larger the voltage drop along the plates. Thus, the discharge time became shorter despite a large amount of available active mass remaining in the bottom part of the plates. Various current-collector designs were evaluated, e.g., one with varying resistance at each height; a side conductor placed along the plates and connected to them at the top, centre and bottom, etc. Results revealed an optimum collector design with which the maximum discharge capacity could be obtained. Furthermore, it was shown that the side conductor markedly improved the discharge performance because the active mass near the connecting parts was appreciably used.

Body surface isopotential maps of normal Japanese children.

Body surface isopotential maps were compared between 52 normal children and 47 normal adults. While sequential changes in body surface potential distribution were similar, 4 significant differences in body surface maps were observed between them: 1) Surface maps of normal children showed less smooth contour of isopotential lines than did those of normal adults. For example, breakthrough minimum was recognized more frequently in children (100%) than adults (65%). 2) Breakthrough minimum appeared earlier in normal children (23.2 +/- 5.0 msec) than in normal adults (29.2 +/- 4.3 msec), and more leftwards on the chest. 3) Forty-seven percent of the children showed positive potentials on the upper and right portions of the anterior chest in the terminal phase of QRS, but this pattern was not observed in normal adults. 4) The maximum at the time of the peak of the T wave appeared more leftward in normal children than normal adults.

Characteristics of a Channel Electron Multiplier for Detection of Positive Ion

The efficiency vs operation voltage characteristics of a channel electron multiplier (CEM) with a negative voltage applied to the entrance cone are investigated in detail. In this negative bias operation, an abnormal increase in efficiency with operation voltage is found, arising from two main mechanisms. One is the change in potential distribution in the cone with the applied voltage. This is because the probability of secondary electrons ejected from the cone being pulled into the channel depends on the potential distribution in the cone. The other is the ionization of particles by leakage electrons from the gap between the CEM exit and the electron collector. Methods of solving these problems are also described.

3-dimensional graphic display of electrocardiograms.

We developed a new method to display a potential distribution of the heart activity on the body surface. Electrocardiograms were recorded from many points distributed regularly on the precordial region. From these electrocardiograms three-dimensional graph of potential distribution was produced by a small digital computer and displayed on the CRT. This graph continuously changes with time according to change of potential distribution like an animation. An interpolation method that we had derived took a short execution time and give a smooth approximated curve. Three-dimentional graphs of electrocardiograms were produced for healthy male subjects. From these graphs a transmission of a wave front of the ventricular activation can be seen as if the wave moves over the picture.

On the Effects of Frequency on Fluorescent Lamp Starting

Many factors affect fluorescent lamp starting. The frequency of applied voltage is one of them. The effect of frequency is attributable to the changes of potential distribution along the tube surface and the voltage drop at the tube end.Analysing the above changes, with the aid of an equivalent circuit, it has become now clear that:(1) At lower tube surface resistances, the starting potential increases as the frequency increases.(2) At higher tube surface resistances, it decreases as the frequency increases.(3) Sometimes, the starting potential shows maximum value at certain frequencies. Above facts are also proved by our experiments.

Influence of a Longitudinal Magnetic Field on an Electrical Discharge in Mercury Vapor at Low Pressure

The effect of a uniform longitudinal magnetic field on a low pressure arc has been investigated in an arc tube with a Hull type cathode and movable and fixed probes. The magnetic field collimated the current flow from the cathode into a luminous beam which disappeared rather abruptly 30 cm from the cathode into a tube-filling glow. This glow was more intense at the axis than in the absence of field. By making the field more intense at the cathode the beam was made to fill the tube and the subsequent glow was indistinguishable from that observed in the absence of field. It thus appeared that a uniform field exercised no constrictive effect on the arc. Distortion of the probe characteristics by the field limited the range within which the probes could be used to low field values at which interesting magnetic effects were still weak. It was demonstrable that the field imparted a transverse stiffness to the arc which caused the transmission of a disturbed condition over large distances in the direction of electron flow. The measurements showed that there was no marked change in electron temperature, gradient, or electron concentration in the presence of a field, and indicated that the limiting cross-sectional distribution of charge as transmitted disturbances die out is the same as in the absence of field. The change of transverse potential distribution with field was found to be roughly in accordance with the modified Boltzmann distribution for the electrons which was previously derived theoretically.

Luminous Discharge Between Lecher Wires in a Partially Evacuated Tube

In experiments with a Gill-Morrell oscillator generating undamped waves less than a meter in length, a study was made of the potential difference between the Lecher wires coupled to the oscillator by enclosing these wires in an evacuated glass tube several wave-lengths long. The oscillator itself employed two type −52 tubes connected in push-pull and it set up radiofrequency currents of 2.5 amperes in the Lecher wires and potential differences in excess of several hundred volts between the wires at positions separated by half wave-length intervals. At these voltage loops for certain critical pressures, between the wires a discharge took place which was photographed as well as employed in a direct study of the standing waves in the wires. The gases used in the tube were air, helium, oxygen, mercury vapor and mixtures of these gases with air. The use of this tube made possible a visual study of the changes in potential distribution as various circuit adjustments were made. A series of double maxima was observed as the length of the line was changed by a half wave-length.