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Notes: An eight-shot pneumatic pellet injection system has been developed for plasma fueling of the tokamak fusion test reactor (TFTR). The active cryogenic mechanisms consist of a solid hydrogen extruder and a rotating pellet wheel that are cooled by flowing liquid-helium refrigerant. The extruder provides solid hydrogen for stepwise loading of eight holes located circumferentially around the pellet wheel. This design allows for three different pellet diameters: 3.0 mm (three pellets), 3.5 mm (three pellets), and 4.0 mm (two pellets) in the present configuration. Each of the eight pellets can be shot independently. Deuterium pellets are accelerated in 1.0-m-long gun barrels with compressed hydrogen gas (at pressures from 70 to 105 bar) to velocities in the range 1.0–1.5 km/s. The pellets are transported to the plasma in an injection line that incorporates two stages of guide tubes with intermediate vacuum pumping stations. A remote, stand-alone control and data-acquisition system is used for injector and vacuum system operation. The eight-shot injection system has been installed and operated on TFTR. The design features, operation, and performance characteristics of the system are described.

Notes: The diamagnetic diagnostic on ATF consists of two systems. The first uses a single-turn diamagnetic loop in a stainless-steel reentrant tube inside the vacuum vessel. Compensation signals are derived from Rogowski coils mounted on the main helical and vertical coil buses. This arrangement provides maximum sensitivity and the fastest time response, but results in signals which are dominated by noise created by the large ATF SCR power supplies. The nonlinear nature of these supplies, and their coupling, requires the use of hybrid noise reduction processing. The analog compensation loops remove the low-frequency components and digital post-processing removes the high-frequency ones. The second diamagnetic signal is derived from a set of saddle loops which respond directly to the Pfirsch-Schlüter current in the plasma. Typical results are presented. This research was sponsored by the Office of Fusion Energy, U.S. Department of Energy, under contract DE-AC05-84OR21400 with Martin Marietta Energy Systems, Inc.

Notes: The recommended treatment for medically fit patients with muscle-invading bladder cancer is usually radical cystectomy. However, transurethral resection of the tumor, partial cystectomy, irradiation and systemic chemotherapy are each effective in some patients. These latter treatments allow bladder preservation and cure as an alternative to radical cystectomy although when used unselectively the survival rates are inferior to those of radical cystectomy.The updated results of conservative surgery, radiation therapy and systemic chemotherapy as monotherapy, as well as strategies of combined modality treatment were reviewed. Based on this review many areas of consensus were reached which include:1. The primary goal of any treatment for a patient with muscle-invading bladder cancer is survival; bladder preservation in the interest of quality of life is a secondary objective.2. Only a small proportion of carefully selected patients may be cured by transurethral surgery alone, or by partial cystectomy alone.3. Radiation therapy is currently the standard bladder-preserving therapy against which all other bladder-preserving methods must be compared.4. Systemic chemotherapy as monotherapy is inadequate and cannot be recommended.5. The addition of cisplatin-containing systemic chemotherapy to radiation therapy or conservative surgery appears to improve local control. While no multi-modality therapeutic regimen has yet been shown to be clearly optimal with regard to local efficacy and minimizing toxicity, monotherapy for bladder preservation is probably not desirable as a routine approach.6. Deferring the patient from immediate cystectomy does not appear to compromise survival, nor does the addition of primary systemic chemotherapy appear to significantly increase the morbidity of cystectomy or radiotherapy.7. All patients treated by bladder-preserving therapy must return to the urologist for regular cystoscopic follow-up so that additional therapy may be started at the earliest opportunity if relapse occurs.8. Bladder substitution is suboptimal compared with a normally functioning, disease-free bladder.9. If alternatives to cystectomy are not considered, little progress will be made in the treatment of muscle-invading bladder cancer.10. Randomized phase III trials must be performed to establish the role of optimal combined modality treatment for bladder preservation, but patient recruitment into such trials may prove difficult unless urologists are prepared to open their minds to the possibility that cystectomy may not be the best treatment for all patients with muscle-invading bladder cancer. Further, urologists must be prepared to have their patients randomized into phase III protocols and investigators must not allow premature publication of findings.

Notes: Summary Bladder-sparing treatment approaches for patients with invasive (of bladder muscle) cancers must be used carefully and cautiously because when radiation is used without discrimination (for patient and tumor selection) and without other modalities (de-bulking transurethral surgery, systemic chemotherapy or intraoperative radiotherapy) the local success rate is less than 50%. The goal is to irradiate only those patients whose tumors will have a fully maintained complete response. To reach this goal will require combining radiation with de-bulking surgery and systemic chemotherapy as well as some patient selection. The intricate multidisciplinary coordination is optimally led by the urologic surgeon from carefully designed guidelines (treatment protocols). It is important that randomized trials of chemotherapy as neoadjuvant to radiation and/or surgery have begun so their potential usefullness is tested before clinicians become prematurely, or possibly incorrectly, convinced of their benefit.