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[en] Topics discussed include: high-pressure diamond cell work; x-ray fluorescence analysis; shroud of turin; laser fusion target inspection; and scanning electron microscope. Organization charts for the M-1 group are included
[en] A sample of presently employed flash x-ray generators is given including low-energy, commercially available systems and high-energy very specialized installations in government laboratories. These flash x-ray sources are compared as to radiographic characteristics. Imaging techniques and materials are surveyed and compared as to their advantages and limitations. A variety of applications of flash radiography are cited including explosive, ballistic, diffraction, crash injury, and fuel injection. Probable near term advances in special techniques are mentioned in cine radiography and film image enhancement. Possible future developments are speculated upon such as flash radiographic applications of computerized axial tomography. The recent recognition of flash radiography at professional society conferences is reviewed. (author)
[en] A cine radiographic technique is being developed by using an inert rocket motor to simulate a burning rocket motor. Because of radiation attenuation in the object and safety considerations for the equipment in an actual test, a high-energy, high-intensity x-ray source was chosen. The source is a 10-MeV linear accelerator with an output of up to 2,500 R/minute at 1 m and a maximum pulse repetition rate of 240/s. Various fluorescent intensifying converter screens are being evaluated. The image from the screen is amplified electronically and recorded on a high-speed camera. This camera gives an output signal which synchronizes the linear accelerator pulse with the camera frame. The images obtained thus far are only crude representations of a resolution gage and a thickness gage superimposed on the object image. (author)
[en] Two articles are studied, the first one: high dose rate brachytherapy in combination with external beam radiotherapy in the radical treatment of prostate cancer: initial results of a randomized phase three trial is the first randomized trial comparing radiotherapy with or without brachytherapy. It confirms the advantage of the increase of dose thanks to the brachytherapy in terms of probability of survival without biochemical recurrence. We note however that the dose by fraction was raised, what can have advantages in prostate cancer if we admit that the ratio alpha / beta is low, but also that the used technique was not optimal towards actual standards, weak total dose, not conformational technique for the first patients, what was able to have an incidence on the results. The second article: prophylactic cranial irradiation in extensive small-cell lung cancer shows a profit of global survival of a preventive brain irradiation at patients affected by evolved small cell lung cancer having answered the chemotherapy. However the article does not present an analysis of efficiency according to the dose (multiple plans of irradiation). If a linear relation between the delivered dose and the efficiency was demonstrated, the optimal dose remains discussed, notably because of the engendered side effects. A study led by Radiation therapy oncology group (R.T.O.G.-0212), tries to answer this question by comparing two fractionations for a total dose from 36 to 25 Gy. Besides the interest of the brain preventive irradiation in the treatment of the evolved lung cancers not at small cells is not established. (N.C.)
[en] The ITER project is considering the inclusion of two sets of in-vessel coils, one to mitigate the effect of Edge Localized Modes (ELMs) and another to provide vertical stabilization (VS). The in-vessel location (behind the blanket shield modules, mounted to the vacuum vessel inner wall) presents special challenges in terms of nuclear radiation (∼3000 MGy) and temperature (100 C vessel during operations, 200 C during bakeout). Mineral insulated conductors are well suited to this environment but are not commercially available in the large cross section required. An R and D program is underway to demonstrate the production of mineral insulated (MgO or Spinel) hollow copper conductor with stainless steel jacketing needed for these coils. A preliminary design based on this conductor technology has been developed and is presented herein.