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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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Total body scintillation counter for hb an subjects. The Los Aldmos Scientific Laboratory has developed a large scintillation counter for recording the total body load of radioactivity. ' The 'subject is placed within the cylindrical counter, so that essentially all emanations arising from radioactive disintegrationsenywhere inthe body are recorded. The instrument is sufficiently sensitive to measure the natural level of radioactivity in tissues of persons who have never been exposed t o any special natural level is therefore ees i ly detected. Any appreciable increase inactivity above this Cardiac effluography with radioisotopes. A t Tulane University, an apparatus has been developed which permits a novel use of radioisotopes inthe analysis of the fundamental processes i n heart action. The heart of a turtle which has been previously injected with tracer potassium (the chief inorganic ionin the heart muscle) i s removed from the animal and connected to,a pipeline providing a constant supply of a physiological salt solution. A s the heart beats, some of its potassium ion, carrying the tracer,is released from the heart muscle cells into the coronary circulation and i s carried out by the circulating fluid. The apparatus (the "effluograph") provides a continuous collection of this fluid on a moving paper strip, with sufficient resolution that it i s possible t o separate as many as 17 samples per second for counting of the radioactivity of the released potassium isotope. means of following the release of potassium accompanying a single cardiac' contraction. The time-course of the phenomenon i s being correlated'with that of the electrocardiogram and of the contraction itself i n an effort t o achieve a better understanding of the basic processes which'connect these three aspects of the heart ' s action, It i s hoped inthe near future t o extend these studies t o mamnalian hearts and t o the behavior of biologic ally active ions other than potassium. The action of cardiac drugs may also be elucidated by this means. This technique has provided the first Use of waste fission praducts for control of trich w ;ANHIVES University of earch group has been investigating the radiosens it iv it y-a larva. The larvae were exposed both i n infected pork or rat IIiuscle, and. after removal, totap water. Im practically.
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a--high doses are required to immobilize the larvae completely, but only. about 5,000 roentgens of X rays or 10,000 roentgens of cobalt 60 irradiation were sufficient in most instances to prevent maturation to adult forms and reproduction following their subsequent ingestions by rats. Somewhat higher doses are required to ensure complete sterilization of the trichi'- the cobalt 60 gamma ray dosages (equivalent to "sterilizing doses") showed complete disorganization of the sexual apparatus. Examination of adult females which had been subjected as larvae to It is hoped that these studies may lead to a practical use of waste fission products in lowering the infectivity of trichinous pork and so contributing to the control of human trichinosis, an important public Electron microscopy of irradiated mammalian cells. A University of Minnesota research group recently reported promising 'developments in the use of electron microscopy of ultra-thin tissue sections in recording radiation damage. The early work has been on gastric and duodenal mucosa of mice, fixed rapidly in vivo with osmic acid within a minute after termination of very brief and intense X-ray exposures; The micrographs show highly localized damage to cell structures, apparently resulting from the action of ions released by the radiation; however, much additional work must be done in order to substantiate this finding. FCDA-AEC briefings. A classified briefing for Mr. Val Peterson, newly appointed FCDA Administrator, and eight of his top staff was held generally the pattern of previous White House and Cabinet briefings, the purpose being to acquaint M r . Peterson with AEC programs and developments pertinent to the national civil defense effort. The briefing was conducted by Chairman Dean and followed A reciprocal meeting was arranged by liaison offices of both agencies on April 23 at which time the FCDA program and objectives were explained gave a presentation depicting the possible magnitude and effects of an atomic attack on the United States. FCDA in attempting to minimize casualties and'damage and their proposed program for carrying out their respohsibilities in event of attack. He described the obstacles faced by Designation of AEC representative on protective construction. In response to an invitation by the Administrator, FCDA, to designate an AEC representative to meet with FCDA staff members on the problem of guidance on certain measures of protective construction, Chairman Dean on April 22, available for consultation pending M r . Corsbie's release from duties with the Test Organization at Nevada Proving Grounds. /Loans of radiation detection instruments and radiation sources. The .!loan of radiation detection instruments to the Texas State civil defense
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agency for use in radiological training courses was authorized. cobalt 60,sources for similar purposes were authorized for State civil defense agencies in Washington, California, and Texas. Instruments were also provided on loan to Program 22 of the Civil . Effects Group, at the current Nevada test operation. This program is sponsored by the FCDA and includes evaluation of radiological defense survey methods by means of actual field training exercises. Industrial Health Conference. In connection with the 1953 Nati'onal . Industrial Health Conference, held this year at Los Angeles, the Division of Biology and Medicine sponsored a one-day meeting on industrial health problems of special interest in AEC operations. discussed included radiation dosimetry, experimental studies of inhalation of radioactive dusts by animals, aspects of the industrial medical programs at Hanford and at ORNL, beryllium toxicity, the ;reatment of liquid metal burns, and therapeutics on radiation injury. AEC and contractor personnel were also well represented both by attendance and participation in sessions of the American Association of Industrial Physicians and of the American Industrial Hygiene Association. tion section of the AIHA voted to continue its identity as a specialized section of the AIHA and initiated plans for one or more sessions oqradiation protection at next year's Industrial Health Conference. The range of subjects Radiation Instrument CataloQ;. During April, 423 copies of the 3rd Edition of the Radiation Instrument Catalog weqe distributed to AEC offices, AEC operating contractors, other government agencies, and contributing first supplement to'the Catalog have been sent to 93 manufacturers of radiation instrument equipment. Invitations to submit information on new products for the (End of UNCLASSIFIED section.) Triiartite Conference on Permissible Doses O n March 30-31 and April 1, 1953, the fourth'TripartiteConference on Permissible Doses was held at Harriman, New York. Twenty-one delegates, including five from the United Kingdom and four from Canada, were present. In general, out of this meeting arose a better understanding and agreement between the participating countries than had previously been noted. .It was possible,to eliminate much of the confusion on standards of measurement which the three countries have been using and to confirm or strengthen standards in current use. It appeared that perhaps some of the stand- .I ards in use in this country are on the conservative si permissible level for radon concentration in mines. (