[en] Anorexia nervosa and bulimia are common eating disorders that are frequently associated with symptoms of bloating, belching, nausea, and vomiting. The authors currently studying this population with Tc-99m TETA to determine the gastric emptying time (ET) and response to metoclopramide. The authors' findings to date show that the majority (80%) of anorexics have a normal ET; the remainder are delayed. The bulimics demonstrate a normal ET in 34%, delayed in 45%, and rapid in 21%. The response to metoclopramide was good in the delayed anorexic patients and in 71% of bulimic patients treated. The extent of rapidity or delay in ET is being compared with the clinical data including age, weight/height, length and degree of disorder, diet, degree of symptoms, and response to drug and diet therapy. This correlation will help determine the incidence and severity of ET abnormality, the relation of disease and symptom severity to ET, and the effect of different treatments based on the ET

[en] To evaluate gastric emptying, 20 patients with anorexia nervosa were given 150 μCi of Tc-99m triethylene tetraamine polystyrene resin in cereal and were imaged in the supine position. Data were accumulated at 5-minute intervals to determine the gastric emptying time (GET). The GET results were divided into three categories: prolonged (10 patients); rapid (eight); and normal (two). Although all patients had symptoms of gastric dysfunction, only 50% had prolonged GET. This study allows the objective documentation of gastric emptying and the separation of patients with rapid or normal GET from those with prolonged GET, who might benefit from metoclopramide

[en] The XR1-1 and XR1-2 (Ex-Reactor) experiments, investigating metallic core melt relocation in boiling water reactor (BWR) geometry were performed in August and November of 1993. The XR1 tests represented the BWR control blade and channel box structures in the lower part of the BWR core as metallic core materials are beginning to melt and drain downwards. The purpose of this experiment program is to examine the behavior of downward-draining molten metallic core materials in a severe reactor accident in a dry BWR core, and to determine conditions under which the molten materials drain out of the core region or freeze to form blockages in the lower portion of the core

[en] To evaluate gastric emptying in anorexia nervosa patients, 26 patients (17 females, two males, ranging in age from 13 to 40 yr) with upper GI symptoms ingested 150-200 microCi [/sup 99m/Tc]triethelenetetraamine polysterene resin in cereal and were imaged in the supine position. Data were accumulated at 5 min intervals to obtain the gastric emptying time (GET). The results of the studies were divided into three categories: prolonged, 13 patients; rapid, 11; and normal 3. Twelve of 13 patients with prolonged GET were given 10 mg metoclopramide i.v. injections; nine of the 12 patients had a good response and three had no response. Five of the nine patients underwent metoclopramide therapy and four of the patients showed benefit from the therapy. One patient discontinued metoclopramide therapy because of somnolence. Although all patients had subjective symptoms of gastric dysfunction, our results indicated only 50% had objectively prolonged GET, and another 50% showed normal or even rapid GET. Therefore, this radionuclide study enables quantitatively objective documentation of gastric emptying, separation of those patients with rapid or normal GET from those with prolonged GET, thereby avoiding the possible side effects from metoclopramide medication, and prediction of effectiveness of metoclopramide therapy in patients with prolonged GET

[en] The XR2-1 (Ex-Reactor) experiment, investigating metallic core-melt relocation in boiling water reactor geometry, was performed on October 12, 1995, following two previous simpler XR1-series tests in August and November of 1993. The XR2-1 test made use of a highly detailed replication of the lower region of the BWR core, including the control blade and channel box structures, fuel rods, fuel canister nosepieces, control blade velocity limiter, and fuel support pieces, in order to investigate a key core melt progression uncertainty for BWR Station Blackout type accidents. The purpose of this experiment program is to examine the behavior of downward-draining molten metallic core materials in a severe reactor accident in a dry BWR core, and to determine conditions under which the molten materials drain out of the core region, or freeze to form blockages in the lower portion of the core. In the event that the draining metallic materials do not form stable blockages in the lower core region, and instead erode the lower core structures such as the lower core plate, then the subsequent core melt progression processes may proceed quite differently than was observed in the TMI-2 accident, with correspondingly different impact on vessel loading and vessel release behavior. The results of the Ex-Reactor tests are preliminary. All of the tests conducted have shown a significant degree of channel box destruction induced by the draining control blade materials. The XR2-1 test further showed that the draining zircaloy melt causes significant disruption of the fuel rod geometry. All of the tests have shown tendencies to form interim blockages as the melts temporarily freeze, but that these blockages re-melt, assisted by eutectic interactions, resulting in the sudden draining of accumulated metallic melt pools

No abstract available

[en] The subject of this paper is to compare the results of the different calculations performed by the benchmark participants in the framework of the OECD Lower Head Failure (OLHF) program. The benchmark consists in the finite element (FE) calculation or in analytical calculations of the mechanical behavior of the OLHF-1 experiment. Seven participants from six countries and seven companies or organizations (AVN, VTT, GRS, UJV, SNL, IPSN and CEA) have performed the benchmark. The OLHF experiment program extends the NRC-sponsored SNL LHF program (NUREG/CR-5582) completed in 1998: these experiments where intended to simulate the thermal/mechanical loads to a 1/4.85-scale model of a reactor pressure vessel. The pressure vessel material (SA533B1 steel) used in these experiments is prototypic of reactor PWR vessel material and has been well characterized by material property testing as part of this program. The OLHF tests advance the results of the previous testing program by examining the effects of large temperature differences across the vessel wall. Large temperature differences in excess of 150-400 K are more prototypic of accident conditions. Most of the participants performed 2-D axisymmetric analyses and doesn't study the crack opening. The global mechanical behaviour of OLHF-1 experiment is well represented but prediction of the maximum vertical displacement is not in good agreement with the experimental value. Failure time and location are in quite good agreement with experimental results but large discrepancies are observed on the mode of failure: creep or plasticity. To improve predictions, more investigation and work is needed on the choice of the failure criteria and failure mode.

[en] Cylindrical ionization chamber descriptions and physical dimensions that are necessary for the calculation of A/sub wall/ and N/sub gas/ are presented. Also included are the corresponding calculated values of A/sub wall/ and N/sub gas//(N/sub X/A/sub ion/)

[en] To evaluate gastric emptying in patients with bulimia, 20 patients (all women, ranging in age from 12 to 49 years) with upper gastrointestinal symptoms ingested 150-200 μCi^99m Tc-triethelene tetraamine polysterene resin in cereal and had scintigraphy in the supine position. Data were accumulated at 5 min intervals to determine the gastric emptying time (GET). The results showed that the gastric emptying time was prolonged in 12 patients and decreased in 8. All 12 patients with prolonged emptying time were given 10 mg metoclopramide intravenously; 9 of these had a good response and 3 had no response. Although all patients had subjective symptoms of gastric dysfunction, the results indicate that about 60% had delayed and 40% had rapid gastric emptying. The findings of two extremes of gastric emptying time remain to be explained, however, this enables (Albibi and McCullum 1983) objective documentation of gastric emptying as this technique (American Psychiatric Association 1980) can separate those patients with rapid GET from those with prolonged GET, who might benefit from metoclopramide. (orig.)

[en] In the frame of the OECD/NEA Working Group GAMA a benchmark problem was conducted in order to determine the ability of current advanced codes to predict core degradation in nuclear reactors. For this purpose, the TMI-2 reactor was selected with a well defined core degradation scenario following a small hot leg break, specified with simple initial and boundary conditions so that the influence of uncertainty of these conditions was minimized. The benchmark sequence can be divided in three parts. For the initial transient, up to the primary system pumps trip, the calculated results are in good agreement. For the degradation phase, up to the reflooding of the core, the results show also a rather good agreement among all participants for global results like total hydrogen production and total mass of molten materials. The variability in these results is comparable or even better than the variability obtained in recent benchmarks on integral tests. In the final phase, the reflooding phase, some results may be questionable as they are apparently in contradiction with experimental findings and with the TMI-2 assumed evolution. Sensitivity studies performed by participants have shown that variations of some key empirical models could induce variations in calculated results of a single participant, which are of the same order of magnitude as the variation obtained when comparing different codes and/or participants. This indicates that some physical processes are still poorly known and inadequately modelled. In summary, the results show a strong robustness of the current codes and a good agreement with large parts of the proposed alternative TMI-2 sequence. That is an evidence for the considerable progress made within the last 20 years. The following organizations have participated in the benchmark study: ENEA (using ASTEC V1.3), GRS (ATHLET-CD Mod 2.1A), IVS (ASTEC V1.3), NRC-SNL (MELCOR 1.8.6), University of Pisa (MELCOR 1.8.5), IRSN (ICARE/CATHARE V2.1), Seoul National University (MAAP 4.03), IKE (ATHLET-CD/MEWA)