Two articles detailing refugee physicians in America and the difficulties that arise for them and for the communities they try to integrate themselves in.

Article on the serology of aerobic aquatic actinomycetes.

The objective of the meeting was to provide a companion meeting to the ''First Symposium on Accelerator Radiation Dosimetry and Experience'' which was held November 3-5, 1965, at the Brookhaven National Laboratory. This first symposium was limited in scope to an intensified discussion of dosimetry techniques. The biology which is associated with high energy radiation was specifically excluded, since it was the original plan to hold a second symposium devoted entirely to biology. Thus the present Symposium was a sequel to the first and they were inseparable in their objectives. Since those attending the BNL Symposium were almost entirely health physicists with a background in physical science and actively engaged in the solution of radiation protection problems at high energy accelerators, it was felt that it would be necessary to begin the BID Symposium with a general review session on radiation biology, in order to provide a biological background for the proper understanding of the later sessions. This first session was arranged to give the health physicist a meaningful transition from fundamental radiobiological considerations to current new research activities in high energy biology. In our opinion, and also based on the comments of several of those attending these objectives were …

We discuss the possibility of using synchrotron radiation to form electron rings having a very high electric field to hold the ions inside the ring. The formulas describing bow the energy and the dimension of the ring change under the effect of synchrotron radiation are derived, and a numerical example is given.

The search for the correct higher symmetry of decay vertices is discussed. It is noted that something higher than SU(3) is certainly valid and colliding lepton beams can help find what it is. SU(6(/sub W/ and its limitations, L = 1, 2 mesons, and the two-photon processes e/sup +/ + e/sup -/ yields e/sup +/ + e/sup -/ + hadrons, and e/sup -/ + e/sup -/ yields e/sup -/ + e/sup -/ + hadrons are considered. (JFP)

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From international metallography society symposium on specimen preparation for metallography; Los Angeles. California, USA (23 Sep 1973). A triode cathodic vacuum etcher has been developed that has a number of advantages over conventional diode etchers. The triode etcher can be operated at specimen voltages well below 1000 V(dc) to minimize mount deterioration and the danger of arcing to the etched surface. Etching voltage and current density can be independently varied so that high current densities can be used with low voltages to provide rapid etching rates while minimizing heating of the specimen. Also. redeposition of sputtered material on the etched surface is reduced because of the low operating pressure (<3 millitorr) of the triode system. At very low voltages (75 to 125 V(dc)) the etching rate is relatively insensitive to crystalline orientation and a polishing action is obtained. This permits the removal of deformed surface layers and even such gross surface defects as the scratches from 600-grit paper without producing significant surface relief. This ion polishing capability has been used to reveal the pore structure of UO/sub 2/ and UO/sub 2/-PuO/sub -specimens by removing surface flow material without enlarging the pores. Details of the design and operation of a simple, …

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Plutonium and polonium assays of the giant kelp revealed that most of the Pu and Po was in the surface scrapings. Both nuclides were concentrated to 1000 times their sea water concentrations; there was usually 200 times more Po activity than Pu. Field experiments using Macrocystis pyrifera showed that Pu and Po accumulated in proportion with time and surface area and that approximately four times more Pu and Po were found on oldest tissues. When glass microscope slides were exposed alongside living plants, deposition rates for Po were identical and Po deposited about 200 times faster than Pu. (HLW)

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Self-scanning photodiode arrays were tested for their ability to measure the spatial distribution of low-energy x rays in a wavelength-dispersive spectrometer. X-ray spectral sensitivity was measured with a calibrated dc source of nearly-monochromatic characteristic-x rays with photon energies in the range of 1.5 to 8 keV. Photodiode response was found to be linear with x-ray flux. Exposure to large doses of copper radiation did not affect sensitivity. A mathematical model that describes the experimental data is presented. It was found that spatial resolving power was lowered by the dispersal of photogenerated charges. This effect was investigated with collimated beams and is described with a formula that predicts the loss of diode signals. (auth)

Data processing for the laser systems in operation at LLL is discussed. Methods for automatic storage, reduction and display using the computers and the Octopus system at LLL are described. This paper briefly describes how this data is compiled, correlated, and displayed. (MOW)

The imaging properties and design principles for an axisymmetric x-ray microscope using a hyperboloid surface preceding an ellipsoidal reflecting surface are discussed. The results of a design study investigating the off-axis resolution of x-ray microcopes are presented. (MOW)

Fuel cycle problems of fusion reactors evolve around the breeding, recovery, containment, and recycling of tritium. These processes are described, and their implications and alternatives are discussed. Technically, fuel cycle problems are solvable; economically, their feasibility is not yet known. (auth)

The evolution of this particular blanket concept is described. The geometry of the mirror reactor blanket and the replacement methods that are employed are described. The sub-module design and its thermal-hydraulic considerations, the nuclear model geometry and compositions, and the nuclear calculational method are described. A brief reference is made to calculational vs. experimental results.

The incentive for high density operation of a tokamak reactor was discussed. It is found that high density permits ignition in a relatively small, moderately elongated plasma with a moderate magnetic field strength. Under these conditions, neutron wall loadings approximately 4 MW/m/sup 2/ must be tolerated. The sensitivity analysis with respect to impurity effects shows that impurity control will most likely be necessary to achieve the desired plasma conditions. The charge exchange sputtered impurities are found to have an important effect so that maintaining a low neutral density in the plasma is critical. If it is assumed that neutral beams will be used to heat the plasma to ignition, high energy injection is required (approximately 250 keV) when heating is accompished at full density. A scenario is outlined where the ignition temperature is established at low density and then the fueling rate is increased to attain ignition. This approach may permit beams with energies being developed for use in TFTR to be successfully used to heat a high density device of the type described here to ignition.

A brief outline of existing medical heavy-ion facilities is given. The beam specifications for future dedicated medical ion accelerators are discussed. Machines capable of delivering dose rates of approximately 1 krad/min in volumes of a few liters are shown to represent existing technology. A cost and performance analysis shows the synchrotrons to be the most economical source for the heavier ions while conventional cyclotrons seem optimal for an exclusive proton facility. It is seen that the incorporation of additional capabilities such as neutron generation or radioisotope production can be achieved at modest incremental costs. In addition to the accelerators, feasible layouts of hypothetical facilities are discussed, and three-dimensional beam scanning is shown to allow the irradiation of large volumes without sacrificing the precise dose localization capabilities of heavy-ion beams. Concepts of quality-controlled engineering and modern computer technology are introduced as a means to obtain the desired high degree of reliability and ease of operation and maintenance.

Applications of x-ray photoemission spectroscopy (XPS) to the study of actinide materials are reviewed. Examples discussed here include the band structures of thorium and uranium metal, the multiplet structure associated with the 5f electron states in oxides of the transuranium elements, the test for temporal configurations in NpO/sub 2/, crystal field splitting of the U 6p/sub /sup 3///sub 2// level in a series of uranyl compounds, mixed oxidation states in Cf/sub 7/O/sub 12/, and a test for the participation of 5f electrons in bonding in a series of uranium compounds.

A measurement system for transuranic aerosols has been designed that will be able to withstand the corrosive nature of stack effluents and yet have extremely high sensitivity. It will be capable of measuring 1 maximum permissible concentration (MPC) of plutonium or americium in 30 minutes with a fractional standard deviation of less than 0.33. Background resulting from /sup 218/Po is eliminated by alpha energy discrimination and a decay scheme analysis. A microprocessor controls all data acquisition, data reduction, and instrument calibration.