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Sequential killing of allogeneic target cells by immune cytotoxic T lymphocytes (CTL) was directly observed by time-lapse microcinematography. Target cells (EL4 lymphoma cells from C56BL/6 mice), coated with Fab fragments of goat antibody to EL4, were immobilized by binding to the floor of a polystyrene tissue culture flask that had been precoated with specifically purified antigoat Fab. On adding immune BALB/c spleen CTL to such target cell monolayers it could be verified by direct observation that individual CTL could sequentially kill several target cells, that the CTL usually separated from the target cell before target cell death, that not all contacted target cells were killed, and that duration of contact was variable and not correlated with subsequent target cell death.

This paper summarizes the elements of photovoltaic power system and clarifies the terminology currently used. The relationship of system efficiency and cost is described particularly for the Balance of Photovoltaic System (BOPS) area. The current status of the BOPS development activity is described. The photovoltaic systems terminology is found to be on the road to standardization. Power conditioning, energy storage, and support structure are found to be BOPS cost and/or efficiency drivers. Although the current BOPS activity has identified low-cost/high-efficiency components, further development work is necessary.

Infestations, populations and distribution of Steatonyssus occidentalis (Ewing) infesting the big brown Eptesicus ftucus , were studied. Adult and immature bats were collected from an attic colony at State College, Pennsylvania, in April and July 1972. All of the adult bats were infested with mites. Mean mite density per adult bat was 5 mites in April and 60 mites in July. In July, 95% of the immature bats were infested with S. occidentalis at a mean density of 30 mites per individual. Mite population structure seemed to be influenced by the maturity of host. The ratio of adult mites to nymphs was nearly 1:1 for adult hosts and approximately 1:5 for immature hosts. S. occidentalis adults and nymphs were randomly distributed on the fur-bearing portions of the adult bats, but were aggregated in the axillary and inguinal regions of the immature bats. The differences in infestation rates, mite densities, population structures, and topographic distributions which were observed between adult and immature hosts were related largely to fur development. The visual examination method of ectoparasite collection detected only 73% of the mites on adult bats but 91% of the mites on the immature hosts.

In the last twenty five years, enormous advances have been made in the area of computer aided design (CAD) resulting from the improvements in the related hardware and software over this period - from the first expensive mainframes of the 1960’s to the present inexpensive microcomputer level hardware system to run its program, the emergence of various geometrical modeling techniques like the wire frame, 2-D, 3-D, and solid modeling etc., and the various user friendly Finite Element Analysis software packages. The important features offered by CAD are computer graphics and its ability to store, retrieve, manipulate and display graphical information with speed and accuracy.

The installation of robots and their use for assembly in space will create an exciting and successful future for the US space program. This proposed research will develop the guidelines and rules for automated assembly in space. It will incorporate the various modifications in the design of the parts and the products in order to ease the assembly.

The Ph1 chromosome is present in 95% of patients with chronic myelogenous leukaemia (CML). The Ph1 chromosome also occurs in 5-25% of children and adults with acute lymphoblastic leukaemia (ALL). This observation raises questions as to whether these diseases are similar or identical. In patients with CML the c-abl and bcr genes are translocated and abnormally expressed. We studied molecular events related to bcr and c-abl in five patients with ALL to determine its relationship to CML. Four had the Ph1 chromosome; the fifth a probable Ph1 chromosome. c-abl and bcr abnormalities identical to CML were detected in four suggesting a common molecular basis. One patient with the Ph1 chromosome and c-abl translocation lacked these molecular changes but had abnormal c-abl gene transcription apparently unrelated to bcr. These data suggest that Ph1 chromosome positive ALL is heterogeneous; in some patients the molecular abnormality is identical to CML; in others c-abl is likewise involved but via a different mechanism.

The cause of bubbles at a glass/Si, glass/SiGe interface, which form when some glasses are fused on Si or SiGe, was determined. Water, bonded as OH groups in the glass, was reduced by the Si at high temperatures to form H2. The gas released by this reaction formed bubbles only in those glasses with low permeability to H2.

The cause of bubbles at a glass/Si, glass/SiGe interface, which form when some glasses are fused on Si or SiGe, was determined. Water, bonded as OH groups in the glass, was reduced by the Si at high temperatures to form H2. The gas released by this reaction formed bubbles only in those glasses with low permeability to H2.

(1978). Do Coaches Make Better Administrators? Journal of Physical Education and Recreation: Vol. 49, No. 5, pp. 32-32.