Design and measurement methods for a lithium vapor box similarity experiment.

The lithium vapor box divertor is a concept for handling the extreme divertor heat fluxes in magnetic fusion devices. In a baffled slot divertor, plasma interacts with a dense cloud of Li vapor which radiates and cools the plasma, leading to recombination and detachment. Before testing on a tokamak, the concept should be validated: we plan to study detachment and heat redistribution by a Li vapor cloud in laboratory experiments. Mass changes and temperatures are measured to validate a direct simulation Monte Carlo model of neutral Li. The initial experiment involves a 5 cm diameter steel box containing 10 g of Li held at 650 °C as vapor flows out a wide nozzle into a similarly sized box at a lower temperature. Diagnosis is made challenging by the required material compatibility with lithium vapor. Vapor pressure is a steep function of temperature, so to validate mass flow models to within 10%, absolute temperature to within 4.5 K is required. The apparatus is designed to be used with an analytical balance to determine mass transport. Details of the apparatus and methods of temperature and mass flow measurements are presented.

NEW DEVELOPMENTS AND APPLICATIONS OF SUPERHEATED EMULSIONS: WARHEAD VERIFICATION AND SPECIAL NUCLEAR MATERIAL INTERDICTION.

In recent years, neutron detection with superheated emulsions has received renewed attention thanks to improved detector manufacturing and read-out techniques, and thanks to successful applications in warhead verification and special nuclear material (SNM) interdiction. Detectors are currently manufactured with methods allowing high uniformity of the drop sizes, which in turn allows the use of optical read-out techniques based on dynamic light scattering. Small detector cartridges arranged in 2D matrices are developed for the verification of a declared warhead without revealing its design. For this application, the enabling features of the emulsions are that bubbles formed at different times cannot be distinguished from each other, while the passive nature of the detectors avoids the susceptibility to electronic snooping and tampering. Large modules of emulsions are developed to detect the presence of shielded special nuclear materials hidden in cargo containers 'interrogated' with high energy X-rays. In this case, the enabling features of the emulsions are photon discrimination, a neutron detection threshold close to 3 MeV and a rate-insensitive read-out.

Inter-ELM power decay length for JET and ASDEX upgrade: measurement and comparison with heuristic drift-based model.

Experimental measurements of the SOL power decay length (λ(q)) estimated from analysis of fully attached divertor heat load profiles from two tokamaks, JET and ASDEX Upgrade, are presented. Data was measured by means of infrared thermography. An empirical scaling reveals parametric dependency λ(q) in mm = 0.73B(T)(-0.78)q(cyl)(1.2)P(SOL)(0.1)R(geo)(0), where B(T)(T) describes the toroidal magnetic field, q(cyl) the cylindrical safety factor, P(SOL)(MW) the power crossing the separatrix and R(geo)(m) the major radius of the device. A comparison of these measurements to a heuristic particle drift-based model shows satisfactory agreement in both absolute magnitude and scaling. Extrapolation to ITER gives λ(q) ≃ 1 mm.

Perception of self and other in major depression.

Previous research on the nature of person perception in depression has been inconclusive. This investigation differs from earlier studies in that extensive free-response descriptions of other people and self were collected from patients with major depression and from nonpsychiatric control Ss. In comparison with control Ss, depressed patients described fewer positive aspects not only of self but also of parents and significant others and reported more negative aspects of these people. Cluster analysis (HICLAS) also showed that more cognitive differentiation of negative self-perceptions (negative self-complexity) was characteristic of clinical depression. In both control Ss and patients, a positive (or negative) view of self was highly correlated (.85 or more) with a positive (or negative) view of parents and significant others. These correlations were significantly stronger than those between self and less important others.

Emotion differentiation. A correlate of symptom severity in major depression.

The relationship of emotion differentiation to symptom severity in depression was investigated. The subjects were 25 patients diagnosed with unipolar major depression. Subjects were clinically assessed using the Schedule for Affective Disorders and Schizophrenia and the Hamilton rating scales for anxiety and depression. In addition, subjects completed a number of self-report measures of symptoms and attitudes. Twelve basic emotion terms were incorporated into free-response attribute lists which subjects used to rate aspects of themselves and of other significant people in their lives. A clustering algorithm (HICLAS) was used to derive a social perception structure from this data for each subject. The differentiation of negative emotion within an individual's structure (NES) was measured by dividing the number of attribute categories containing negative emotions by the total number of categories in that person's structure. The results indicated that NES is a significant correlate of depressive symptomatology independent of self-esteem and other variables. Relatively undifferentiated emotion structure (low NES) was associated with significantly higher levels of depressive symptomatology.

A measure of paradigm beliefs about the social world.

This study examined the reliability and construct validity of, along with age differences in, a measure of paradigm beliefs about the social world, beliefs that have been proposed to develop across the adolescent and adult life span. The scale is a 27-item, forced-choice preference measure of absolute, relativistic, and dialectical paradigm beliefs. In a series of investigations with 445 subjects, ranging in age from 16 to 83 years, it was shown to have good internal consistency and test-retest reliability, and both convergent and discriminant validities. It predicted performance on an in-depth interview about paradigm beliefs and was related to two other measures of paradigm beliefs. It was not related to selected personality variables (i.e., social dogmatism, intolerance of ambiguity and social desirability); nor was it related to a measure of verbal intelligence. The scale also showed predicted developmental trends, supporting its utility for developmental research.

Toxoplasmosis in Atlantic bottle-nosed dolphins (Tursiops truncatus).

A female Atlantic bottle-nosed dolphin (Tursiops truncatus) and her calf were found beached on Picnic Island in Tampa Bay, Florida, USA. Despite therapy the animals died. Necropsy revealed severe pneumonia and lymphadenopathy in the mother and the calf, gastric ulcers and infection with the stomach digenean Braunina cordiformis in the mother, and a large, pale liver in the calf. Toxoplasma gondii was identified by light and electron microscopy and by immunohistochemistry in tissues of both animals. Toxoplasma gondii was associated with interstitial pneumonia, necrotizing adrenalitis, and cardiac myonecrosis in the mother and with lymphoid necrosis in both dolphins. The source of infection and the relationship to the recent dolphin beachings along the eastern seacoast of North America are unknown. This is the first report of toxoplasmosis in cetaceans.

Giant neural systems in the inner retina and optic nerve of small whales.

Giant neural cell systems (dendrites, cell bodies, and axons) are present among more usual structures in the retina and optic nerve of the small whale (dolphin) Tursiops truncatus retina. Giant cell body dimensions range up to 75 microns in diameter. Nuclei of the cells are frequently larger (greater than 20 microns) than nearby ganglion, bipolar, and receptor cell bodies. The presence of the giant cell system and giant elements in the nerve fiber layer agree with the unusually broad fiber spectrum of the dolphin optic nerve where more than 6% of the axons are greater than 15 microns in diameter. Smaller axons in the size distribution are typical of dimensions found in terrestrial mammals. The axon estimate totaled 157,000 per optic nerve. The giant cell-axon systems of the whale retina may be a unique expression of the large ganglion cell-axon (transient or "Y" functional unit) systems recently identified in terrestrial mammals.