Study of techniques for the reduction of creep in plated wire memories Final report, 28 Jun. 1967 - 28 Aug. 1968

Magnetization reversal in thin films of plated wire memory element

The Effect of Vincristine Sulphate on the Axoplasmic Flow of Proteins in Cultured Sympathetic Neurons

The effect of vincristine sulphate on the axoplasmic flow of labelled proteins in neurites of chick embryo sympathetic neurons growing in tissue culture was studied by autoradiography. In control neurons most of the 3H-proteins synthesized during a 90-min pulse with a 3H-amino acid were localized in cell bodies. There was a diminishing gradient of labelled proteins in the neurites which was highest in portions adjacent to the cell bodies and lowest at the periphery. During a physiological chase there was a gradual increase in the amount of label in the neurites, so that after a 15-h chase even the most peripheral portions were well labelled. This indicates that a portion of the labelled proteins synthesized in the cell bodies are transported peripherally into the neurites. The centrifugal movement of labelled proteins in neurites was markedly decreased when cells were grown in medium containing 10 µg/ml vincristine sulphate. After a 15-h chase in the presence of drug only a small amount of label was in the peripheral portion of the neurites. Treatment with vincristine did not decrease the rate of amino acid incorporation or alter the rate of protein turnover during the course of the experiment. Thus an explanation of the results based on an altered rate of total cell protein synthesis or degradation is unlikely. The capacity of sympathetic neurons to take up and concentrate exogenous [3H]norepinephrine in their neurites was only slightly reduced by vincristine. This indicates that at least some cellular activities requiring metabolic energy are relatively unaffected by the interruption in axoplasmic flow caused by vincristine and that the mechanism by which vincristine interferes with axoplasmic flow does not involve general cellular toxicity. The major morphological differences between control and vincristine-treated neurons were the absence of microtubules and the presence of crystal-like structures within the cells. The relationship between the effect of vincristine on the axoplasmic flow of proteins and the arrangement of the microtubule system is discussed

Assessing the status of urban public school desegregation :

A preliminary examination of desegregation techniques revealed that among elementary schools the combination of pairing and clustering with rezoning proved most successful in reducing racial isolation (operationalized as a change in the index of dissimilarity). For secondary schools the most effective technique was rezoning. These two techniques were associated, in the bivariate case, with the lowest amount of white enrollment loss as well. A multiple regression analysis also showed the most effective desegregation technique to be of some importance (although not statistically significant) in achieving desegregation success when various external, community, and district level forces were taken into account. In the multivariate case, the specific technique was of greater import at the elementary than the secondary level. Other features of the desegregation process, especially support by school officials, were important predictors of desegregation success as well, although the most powerful forces were federal coercion (positive) and size of district (negative). A multivariate analysis of white enrollment change for these 52 districts confirmed recent research that school desegregation does produce a significant one-time decline in white student enrollment. The most important predictor of white student withdrawal was percentage black in the school system.The research concludes that desegregation process variables are important contributors to desegregation success, and certain desegregation techniques may work better than others.Employing a relatively new data collection and aggregation method known as the case survey method and a theoretical framework that conceptualizes school desegregation as a public policy that must be implemented at the local level, an attempt is made to assess the impact of three types of influence--external forces, school district characteristics, and desegregation process variables (including desegregation strategies)--on two school desegregation outcomes: the success of school districts in ending racial isolation (desegregation success) and white enrollment decline (generally referred to as "white flight")

Design, development and test of shuttle/Centaur G-prime cryogenic tankage thermal protection systems

The thermal protection systems for the shuttle/Centaur would have had to provide fail-safe thermal protection during prelaunch, launch ascent, and on-orbit operations as well as during potential abort. The thermal protection systems selected used a helium-purged polyimide foam beneath three rediation shields for the liquid-hydrogen tank and radiation shields only for the liquid-oxygen tank (three shields on the tank sidewall and four on the aft bulkhead). A double-walled vacuum bulkhead separated the two tanks. The liquid-hydrogen tank had one 0.75-in-thick layer of foam on the forward bulkhead and two layers on the larger area sidewall. Full scale tests of the flight vehicle in a simulated shuttle cargo bay that was purged with gaseous nitrogen gave total prelaunch heating rates of 88,500 Btu/hr and 44,000 Btu/hr for the liquid-hydrogen and -oxygen tanks, respectively. Calorimeter tests on a representative sample of the liquid-hydrogen tank sidewall thermal protection system indicated that the measured unit heating rate would rapidly decrease from the prelaunch rate of approx 100 Btu/hr/sq ft to a desired rate of less than 1.3 Btu/hr/sq ft once on orbit

Pollination ecology of Agave palmeri in New Mexico, and landscape use of Leptonycteris nivalis in relation to Agaves

Where animals spend time can provide important clues to their ecological needs, but this information is very difficult to obtain for small volant animals. The research described in Chapter 1 was an attempt to discern how L. nivalis utilize the landscape in relation to the distribution of Agave havardiana in Big Bend National Park, Texas. I found that although the landscape use of Leptonycteris nivalis is centered on habitat with high concentrations of blooming A.havardiana, it is not restricted to those areas, and furthermore adults and juveniles may differ in their behavior. Adult females may remain near food sources in order to replenish energy stores lost to migration and the demands of reproduction, whereas juveniles may feed early in the evening and then undertake occasional far-reaching expeditions, perhaps in order to create a navigational map. If this behavior is widespread among juveniles, it emphasizes the need to carefully assess the risk of constructing wind-turbine energy facilities not just within agave-rich habitat, but anywhere near the range of this endangered bat species. The research described in Chapter 2 focused on documenting the importance of flowering agaves as a food resource for the many vertebrate and invertebrate, diurnal and nocturnal visitors. I found that A. palmeri was visited by a wide variety of vertebrate and invertebrate visitors, many of which are pollinators of other plants, and that there was considerable variation in visitation rates in space and time - in fact, bats were not even observed at one of the study sites. Increased visitation was associated with larger plant sizes for all visitor types assessed. In Chapter 3, I explored how the fruit and seed production of A. palmeri at these three sites were affected by the plants morphology, phenology (timing of bloom), prior reproductive success, and the patterns of visitation by different animal guilds. Models indicated that bats were the most effective visitors, because periods with high bat visitation rates also had very high seed. Periods with high bird visitation resulted in many fruits but with poor seed set, possibly indicating that they are responsible for some degree of reproduction, though the exact mechanism is not clear. Floral branch position interacted in a complex manner with prior fruit set, affecting fruit set, seed set, and mean seed mass. Plants with high prior fruit set showed decreased seed set in fruits on late-blooming branches, possibly indicative of resource limitation

Whole body interaction

In this workshop we explore the notation of whole body interaction. We bring together different disciplines to create a new research direction for study of this emerging form of interaction

Compensation for Pension Benefit Losses in Unlawful Dismissal

This paper describes, firstly, how the real-world pension benefit losses of an unlawfully dismissed employee are dictated by three main variables: the benefit structure of the plan; the legal structure of the plan; and the employee\u27s position in the labour market. Secondly, it shows that the common law measure of damages in a wrongful dismissal action fails to compensate adequately those losses. In contrast, the measures of damages in collective agreement arbitration, and in adjudication pursuant to section 61.5 of the Canada Labour Code\u27 create the potential for a more realistic approach to compensating the employee for his real-world losses. Thirdly, comparison is made with the more fully developed jurisprudence under the British unfair dismissal legislation. Fourthly, some guidelines for compensating the real-world pension losses of the employee are suggested for Canadian legal umpires