Cybernetic jewelry: ornament for the information age

Although jewelry has historically been equated with hardware, the advent of the single-chip CMOS microcomputer allows a redefinition in terms of software. A radically different new kind of jewelry is presented, based on LCD graphics controlled by an on board microcomputer. The revolutionary potentials of this new jewelry, along with its unique requirements and problems, are illustrated by examples from the author's personal experiences in developing this novel medium.     

Study of TRH in the postganglionic sypnasis of the isolated human vas deferens

Cummulative dose-response curves to l-noradrenaline and in presence of different concentrations of TRH (10(-3), 10(-4), 10(-5), 10(-6), 10(-7), and 10(-8) M) were investigated. 25 segments of vas deferens (escrotal tract) were obtained from different surgical patients of urological disorders. At the lower concentration (greater than 10(-7) M), we can not appreciate any influence of TRH on the l-noradrenaline response. Nevertheless there was a reduction of response to l-noradrenaline, with displacement of the curves to the right side, for the high concentrations, and a proportional ratio to the concentration to TRH.     

Tibial torsion?

A longitudinal study evaluating the degree of rotation of the bimalleolar axis of tibia and fibula at birth, 6 month, 12 months and 24 months revealed a gradual statistically significant external rotation from a mean of 4 degrees at birth to a mean of 11 degrees at 24 months. There was no correlation with the sex or race of the child or with the age at which the child began independent walking. It is concluded that this external rotation is a part of normal growth and development of the infants' lower extremities.     

AN INVESTIGATION OF THE WARM PRESTRESSING (WPS) EFFECT IN A533B WELD METAL

Abstract— The WPS effect has been shown to be beneficial in increasing the lower shelf fracture toughness of A533B weld metal for both the load-unload-cool-fracture (LUCF) and the load-cool-fracture (LCF) cycles. The LCF cycle gives a greater apparent increase in fracture toughness than the LUCF cycle but only a small increment of load in the lower shelf region is needed to propagate failure compared with a much increased fracture load which is required in the LUCF case. Models predicting the increase in apparent fracture toughness by superposition of the stress and strain distributions from each step in the prestress cycle are shown to be non-conservative for failures occurring in the lower shelf brittle regime. There is evidence for the operation of a "microcrack blunting" mechanism, but the extent to which it contributes to the WPS effect is small. Stress-relief heat-treatments after prestressing remove nearly all the beneficial effects of WPS. Residual stresses clearly play an important role in the WPS phenomenon, and the models successfully predict experimentally observed trends. Prestressing "deactivates" failure initiation from the larger inclusions in the weld metal. This however does not affect the intrinsic fracture toughness of the material. Fracture in this weld metal, where initiation sites (inclusions) abound, appears to be a co-operative process, and fracture is controlled by inclusions of the mean (and hence most plentiful) diameter rather than the maximum diameter.     

Development of the high-pressure electro-dynamic gradient crystal-growth technology for semi-insulating CdZnTe growth for radiation detector applications

The high-pressure electro-dynamic gradient (HP-EDG) crystal-growth technology has been recently developed and introduced at eV PRODUCTS to grow large-volume, semi-insulating (SI) CdZnTe single crystals for room-temperature x-ray and gamma-ray detector applications. The new HP growth technology significantly improves the downstream CdZnTe device-fabrication yield compared to earlier versions of the HP crystal-growth technology because of the improved structural and charge-transport properties of the CdZnTe ingots. The new state-of-the-art, HP-EDG crystal-growth systems offer exceptional flexibility and thermal and mechanical stability and allow the growth of high-purity CdZnTe ingots. The flexibility of the multi-zone heater system allows the dynamic control of heat flow to optimize the growth-interface shape during crystallization. This flexibility combined with an advanced control system, improved system diagnostics, and realistic heat-transport modeling provides an excellent platform for continuing process development. Initial results on large-diameter (140 mm), SI Cd_1−xZn_xTe (x=0.1) ingots grown in low temperature gradients with the HP-EDG technique show reduced defect density and complete elimination of ingot cracking. The increased single-crystal yield combined with the improved charge transport allows the fabrication of large-volume, high-sensitivity, high energy-resolution detector devices at increased yield. The CdZnTe ingots grown to date produced large-volume crystals (≥1cm³) with electron mobility-lifetime product (μτ_e) in the (3–7) × 10⁻³ cm²/V range. The lower-than-desired charge-transport uniformity of the HP-EDG CdZnTe ingots is associated with the high density of Te inclusions formed in the ingots during crystallization. The latest process-development efforts show a reduction in the Te-inclusion density, an increase of the charge-transport uniformity, and improved energy resolution of the large-volume detectors fabricated from these crystals.     

Myocardial function during hypoxia in the presence of different buffers

Electrically driven rabbit left atria were exposed to 20 min periods of either hypoxia or anoxia in the presence of a bicarbonate-phosphate buffer, a Tris buffer [tris (hydroxymethyl) aminomethane hydrochloride] or combination of both. The bicarbonate-phosphate buffer system was shown to be important for tissue survival during hypoxia or anoxia whereas recovery was diminished in the presence of Tris only. Stimulus threshold and arrhythmias were shown to increase for atria in Tris. Oxygen consumption determinations on both spontaneously beating right atria and quiescent left atria showed no difference between pre- and post-hypoxia or between different buffers. Tris was shown to elicit a positive inotropic effect without an increase in O2 consumption.