In this paper some studies on enzyme properties which are believed to be pertinent to antibodies will be discussed. The particular studies chosen are; (a) the evidence that residues far removed from each other in the sequence play vital roles at the active site; (b) indications on the size of the active site; and (c) evidence for flexibility at the active site. Since the relation between enzyme and antibody is of primary interest an attempt will be made to emphasize the fundamental conclusions derived from the observations and to evaluate critically the deductions on structure and function which derive from these conclusions.

The sexual reproductive ability of a forest exposed to low level ionizing radiation is dependent on the sensitivity of primordial differentiation, meiotic processes leading to the formation of gametes, fusion of the gametes, and subsequent growth of the sporophytic generations. In this report it was shown that the initiation of reproductive primordia in Pinus rigida, Quercus ilicifolia, Quercus alba and Quercus coccinea is not unusually sensitive to irradiation. Trees which had been severely damaged by chronic low level ionizing radiation (4 to 12 r/20 hr day) were able to differentiate floral structures and produce viable seed. However, flower phenology was retarded, and pronounced morphological aberrations were present. It is suggested that this delay may be the result of a reduction of endogenous growth substances.

Ionizing radiation is useful to plant breeders in obtaining mutations beneficial from an economic point of view. This report, however, concerns our basic knowledge of radiation: attention is here directed to some effects of low level radiation on the R₁ progeny. Approximately one third of the land area of the United States is covered by forest; thus, forest trees form an important component of our natural wealth. It is therefore our obligation to know how these forests will react to low level ionizing radiation. Although this type of radiation might accompany atomic explosions, its effects may not be evident for a number of years.

The propagation of clonal varieties of some orchids is at times exasperatingly slow and occasionally an almost futile effort. Clonal multiplication is generally confined to dividing mature plants and to starting plants from pseudobulbs. There is, of course, the specialized technique for obtaining Phalaenopsis plantlets from the aseptic culture of inflorescence nodes, but this is basically the same thing as propagating plants from pseudobulbs. In certain cases it is highly desirable to rapidly multiply certain clones of orchids. Awarded varieties could thereby be dispersed with great rapidity where now it may take decades for some clones to became fairly common. Commercial flower production would be very much enhanced if certain desirable clones could be multiplied ad infinitum within a short time. Orchid flower production could then be placed more on a par with many of the other cut flowers and the clonal peculiarities of some of the current hybrids could be pampered instead of ignored. This paper describes a tissue culture method for the rapid propagation of Cymbidium clones

The potassium-argon age of the Sikhote Alin iron meteorite has been determined. The value is 1.7 + 0.2 x 10⁹ years. Previous lead data suggest an age of 4.6 x 10⁹ years . The date of solidification may be the sum of these two ages.

In order to perform the various experiments with a bubble chamber, a high intensity flash tube is used. This report briefly describes the power supplies designed and constructed to power these lamps.

The power supplies designed and constructed to power high intensity flash tubes used in bubble chamber experiments are briefly described and are accompanied by a schematic diagram of the layout. (D.C.W.)

A tranistorized d.c. coupled amplifier having very good gain stability, as well as very low drift of the output d.c. level, has been designed. Low frequency input signals with an amplitude of .04 to 2 volts peak-to-peak, approximately, coming from a low impedance source (voice soil of a speaker system) are amplified to an approximate peak-to-peak amplitude of 4 volts. The output is intended to drive a load of the order of 100 kohm.

The analyzer can be operated either internally or externally. The 10 ma germanium discriminator is quiescently biased to 8.5 ma in its low-voltage state. An input signal current of 3.5 ma or more triggers it to its high voltage state. This triggers the oscillator. The oscillator signal is buffered and mixed in the bridge modulator with the reference radiofrequency signal from the cyclotron. The low-frequency beat note from the bridge modulator is squared up and passed to the beat zero univibrator which generates 0.7 mu sec signals each time the beat note passes through zero from positive to negative. The trailing edge of the beat zero univibrator is employed to terminate the time-of-flight measurement and to control the servo measurement. Drawings are included. (M.C.G.)

The object of this report is to acquaint the operator with the operational and technical aspects of the beam current integrator as well as the theory of the system operation. The design and operation of a beam current integrator are described, and the theory of operation is discussed. The instrument has two channels. The console channel is designed to measure the accumulation of charge received by a target during a period of a day no matter what the range used in the experimenter's channel. An analysis indicated that this unit will measure the accumulation of charge by a target to an accuracy of 0.1215% assuming that the constant error due to shorting the integrating capacitor is accounted for. The instrument is ranged to handle from 0.5 to 500 mu a of beam current. (M.C.G.)

A digital-to-analog converter is described which is a part of a system that converts punched-tape digital data to analog data in a series of points drawn by an x-y plotter. The converter is designed to plot accurately tapes that contain information other than coded numerical coordinates. Operation of the converter is also described along with format requirements and power supplies. (J.R.D.)

Most existing electron synchrotrons use betatron start for initial acceleration of the particles. The subsequent synchrotron acceleration is then performed with a nearly constant radio-frequency. Investigation of the effect of turn-on rate and initial energy spread is made mathematically. Several advantages are seen for such a technique. (D.C.W.)

This is a preliminary report on the magnetic measurements taken to date on the AGS experimental magnets. It mainly summarizes the results which were necessary for the setting up of the proton separated beam in August 1961. A few curves on information obtained since then are included. When the study is finished, a complete report on all phases of the work, including the methods used, will be forthcoming.

The efficiency of multiple traversal targets is defined as the probability that a proton dies by making a nuclear collision in the target rather than by hitting the limit of the synchrotron aperture. The efficiencies of Be, Al, Cu, and Pb targets are shown for 15 and 30-Bev protons in the Brooknaven AGS. Beryllium was found to be the most efficient. (M.C.G.)

Four methods of rebunching protons within Brookhaven's AGS are discussed. The first method involving switching off the old r-f and switching on the new r-f simultaneously with the new r-f increasing adiabatically seems impractical. Two other methods utilize gradual removal of the old r-f voltage and introduction of the new r-f voltage, or the reverse. Removal of the old r-f voltage followed by introduction of the new seems to give the best results. Several phase diagrams are included. (D.C.W.)

Maintenance of polarization of polarized protons in a linear accelerator is known to be feasible. Circular accelerators present a different problem, and the investigation of the interaction of orbit dynamics and particle polarization in general is undertaken. The equation of motion of the spin vector of a charged particle in a magnetic field as formulated by Bargmann, Michel, and Telegdi is utilized in the study of depolarization for several accelerators. High values of depolarization are obtained, and means for avoiding such depolarization are suggested. (D.C.W.)

Description of a computer program which optimizes the locations and strengths of magnets for experimental beams at the Brookhaven AGS written for the IBM 7090 computer. Layout, method, and routines are given particular attention, and representative data cards are shown.

An investigation was made of Cosmotron intensity versus time through the entire time interval from the beginning of injection to the completion of r-f capture. The induction electrode signal was used for the instantaneous measurement of beam intensity. Oscilloscope displays of the signal were photographed and traced. Base lines were filled in on the tracings and the area of the pulses measured with a polar planimeter. It was found that the relation losses of beam intensity increase with injection intensity (total injected charge), and that most of the losses take place in the time interval between the end of injection and the completion of the first synchrotron oscillation

Use of the Smith chart in studying stub tuners is demonstrated. Several properties of the tuners are shown, and charts for various wave length spacings, tuning trajectories, and admittances are included.

Technique used in deriving values of the linac ball tuner settings to produce various fields is discussed briefly, and tables showing ball tuner change numbers and values used in making up the ball tuner change numbers are given.

This report describes the design procedure for a reflectometer or directional coupler to replace the probe part of the D07-1020 assembly used at the Brookhaven Alternating Gradient Synchrotron linac. Mathematical treatment and diagrams of various reflectometers are included.

Two methods for measuring target efficiencies are briefly discussed. The second method puts an upper bound on the efficiency and permits observation of instantaneous efficiency, thereby aiding location of losses. Measurements agree well with conventional radiochemical values.

A summary of the dynamic behavior of the proton bunches in the Brookhaven Alternating Gradient Synchrotron (AGS) has been given previously. In these reports, the usual linearization of the differential equations involved has been made and the theory was restricted to well bunched beams. The linearized approach is no longer valid at transition where the actual phase angle of the bunch can differ appreciably for a short time from the stable phase angle Φ₀. In this report the non-linearity of the differential equations for phase oscillations will no longer be neglected. At transition the beam is slow enough so that the electronics of the bootstrap system can be considered as being ideal and the radius servo loop can be characterized by one time constant. Under these assumptions the analysis can be carried out in a two-dimensional phase plane. The essential new result will be the short existence of a stable equilibrium point for the bunch motion not coinciding with Φ₀. The results here derived have been tested experimentally and at least a qualitative agreement was found. However, the conclusions are no more valid if debunching takes place since we have still neglected the finite bunch width.

A uniform intensity flat top spill-out cannot be obtained by manual control for two reasons: 1. The horizontal density of the internal beam of the Cosmotron is far from uniform. As a result, a manually controlled linear motion of the internal beam into a target will result in a non-uniform spill-out intensity. 2. Stability requirements of the Cosmotron magnet voltage are not easily met without feedback because of inherent component stability. The proposed servo system will sense the external beam intensity, and correct the magnet voltage to keep this intensity constant. This servo must operate through the transfer function of the main ignitron system and the flat top filter. Both of those transfer functions impose special problems.