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The goal of this SBIR program was to provide authorable, dialog-enabled agents for tutoring and performance support systems. Users interact with agents who carry out strategies and goals and can engage in mixed-initiative dialog via a natural language understanding and generation system. Non-programmers can author new domains and scenarios and create new dialog agents. The dialog system is authorable by non-computational linguists. The system has two types of agents, Mentor agents and Conversational agents. The Mentor agent is a simulated subject matter expert (SME) that provides troubleshooting and problem solving advice. Mentor engages in a dialogue with trainees, helping them solve problems by taking them through logical courses of action and asking and answering domain-specific questions. Conversational agents are used for role-playing scenarios. The only real difference between the two agents is that Conversational agents do not have specific problem solving strategies. Both Mentors and Conversational agents have domain specific knowledge and access to a common sense knowledge base. This report describes the capabilities and limitations of results of this Phase II effort. more...

Thapsigargin depletes intracellular Ca 2+ stores by its inhibitory effect on the Ca 2+ pumps, which unmasks an aspecific Ca 2+ leak from the stores. This aspecific Ca 2+ permeability of the stores was further investigated using 45 Ca 2+ fluxes on intact and permeabilized A7r5 smooth-muscle cells. Stores in intact cells were found to be more leaky for Ca 2+ than those in saponin-permeabilized or Staphylococcus aureus α-toxin-permeabilized cells, which suggests that a cytosolic factor may be involved. Supplementing the medium bathing the permeabilized cells with a submaximal Ins(1,4,5)P 3 concentration increased the leakiness of the stores. Glutathione also increased the aspecific Ca 2+ leak. This effect occurred with both the reduced and the oxidized form but reduced glutathione was more effective. Our data show that basal Ins(1,4,5)P 3 levels and glutathione can contribute to the relatively high Ca 2+ leak in intact cells. The washing out of these substances during permeabilization can reduce the aspecific leakiness of the stores. more...

In a case of fetal anaemia due to pure red cell anaemia (Blackfan-Diamond syndrome), two-dimensional fetal Doppler echocardiography revealed an altered blood flow velocity pattern with entire incorporation of the atrial contraction component in the early passive filling phase of the right ventricle. Intracardiac blood velocities were increased, whereas cardiac output was only moderately increased. The fetal heart rate was normal. It is concluded that in fetal anaemia the compensatory mechanisms are limited and restricted to an increase in stroke volume. The hypothesis that chronic fetal anaemia is associated with ‘high output cardiac failure’ corresponds well with the present findings. The technique described may prove to be useful in the early diagnosis of fetal anaemia. more...

We have investigated platelet [3H]imipramine binding in normal controls and patients with primary endogenous depression (unipolar and bipolar) or schizophrenia. Absolute Bmax values did not differ between subgroups. However, when circannual variation of binding was taken into account by expressing results as percentages of normalised values derived from the multiple linear regression of Bmax values as a function of time of sampling, schizophrenic patients were found to have higher Bmax than normal controls. There was no significant difference between depressed patients and controls, nor between patients exhibiting plasma cortisol suppression and non-suppression after the dexamethasone suppression test. A significant negative correlation was found between relative Bmax values and cerebrospinal 5-HIAA levels in depressed patients. more...