[Molecular pathology of sarcomas. Update on the research group "Molecular Diagnosis of Sarcomas"]. / Molekularpathologie von Sarkomen. Erste Ergebnisse des Sarkomforschungsverbundes KoSar.

To establish precise diagnostic algorithms and standardised treatment of sarcomas in specialized centers, the interdisciplinary research group KoSar (sarcoma competence network) has been funded by German Cancer Aid. A sarcoma tissue repository and a diagnostic reference center have been set up, presently containing about 1000 accurately diagnosed sarcomas of different entities. Significant gene expression profiles for synovial sarcomas, leiomyosarcomas, myxoid liposarcomas and a small profile for myxofibrosarcomas as well as a new classification of angiosarcomas were defined. We systematically searched for activated signal transduction pathways in sarcoma cell lines and xenograft transplant models and candidate targets for molecular therapies were identified. Based on these results first clinical studies have been initiated by the German Interdisciplinary Sarcoma Study Group (GISG).

Psychophysical and physiological evidence for a precedence effect in the median sagittal plane.

A listener in a room is exposed to multiple versions of any acoustical event, coming from many different directions in space. The precedence effect is thought to discount the reflected sounds in the computation of location, so that a listener perceives the source near its true location. According to most auditory theories, the precedence effect is mediated by binaural differences. This report presents evidence that the precedence effect operates in the median sagittal plane, where binaural differences are virtually absent and where spectral cues provide information regarding the location of sounds. Parallel studies were conducted in psychophysics by measuring human listeners' performance, and in neurophysiology by measuring responses of single neurons in the inferior colliculus of cats. In both experiments the precedence effect was found to operate similarly in the azimuthal and sagittal planes. It is concluded that precedence is mediated by binaurally based and spectrally based localization cues in the azimuthal and sagittal planes, respectively. Thus, models that attribute the precedence effect entirely to processes that involve binaural differences are no longer viable.

On the origin of the enlarged melodic octave.

The perceptual octave is larger than the physical octave, i.e., most listeners perceive that two tones are an octave apart when their frequency ratio is greater than 2. This result is known as the octave enlargement effect. There are two theories for the effect, one of them a central template theory, the other a peripheral timing theory. In principle, it is possible to determine which theory is better by discovering whether or not octave enlargement occurs for centrally generated dichotic pitches such as the Huggins pitch. Experiments show that octave enlargement does indeed occur for Huggins pitch. This is the result predicted by the central template theory, but it can be argued that the result does not entirely eliminate the timing theory. A detailed examination of the two theories shows that each requires revision in order to make the octave enlargement prediction follow logically from its premises. The central template theory requires the auditory system to differentiate excitation caused by different harmonics of a complex tone on some basis other than place of excitation. Neural synchrony is suggested as a basis. The timing theory, originally formulated in terms of a neural interspike interval timing, can be made internally consistent by replacing the neural interspike-interval circuit by a neural autocorrelator.

Auditory demonstrations on compact disk for large N.

The popular compact disk entitled Auditory Demonstrations, sponsored by the Acoustical Society of America, includes a number of demonstrations that lead to quantitative results. Those demonstrations are evaluated here in the context of a sizeable class in a lecture room. Demonstrations concern masking, loudness, and pitch; specifically they are numbers 2, 3, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 20, and 25. The evaluations find that most of the demonstrations successfully illustrate psychoacoustical principles in a classroom context; others are less successful or require special circumstances for success. Explanations for success and failure are offered, together with some suggestions for optimizing the chances of success.

A "magic" aid for hypnosis and suggestion in crisis management: a brief communication.

Within the context of crisis management, in certain cases the transfer of a small object from therapist to patient has had positive outcomes. Examples of the use of this "magic" aid are provided with some background and a tentative rationale. Caution regarding its use is suggested.

Localization of sound in rooms, II: The effects of a single reflecting surface.

Auditory localization was studied in a room bounded by a single acoustically reflective surface. The position of that surface was varied so as to stimulate a floor, a ceiling, and left and right side walls. The surface was eliminated in one condition so that we could examine localization in free field for purposes of comparison. Using a source identification method we assessed the influences of these various room configurations on the localization of both slow-onset and impulsive sine tones of low frequency (500 Hz). We also measured the steady-state interaural-time-difference (ITD) and interaural-intensity-difference (IID) cues available to subjects in the different room configurations and compared these data with the perceptual judgments. Our results indicate the following: (1) A sound must include transients if the precedence effect is to operate as an aid to its localization in rooms. (2) Even if transients are present the precedence effect does not eliminate all influences of room reflections. (3) Due to the interference of reflections large interaural intensity differences may occur in a room and these have a considerable influence on localization; this is true even at low frequencies for which IID cues do not exist in a free field. (4) Listeners appear to have certain expectations about the reliability and plausibility of various directional cues and perceptually weight the cues accordingly; we suggest that this may explain, in part, the large variation in time-intensity trading ratios reported in the literature and also the differing reports regarding the importance of onsets for localization. (5) In this study we find that onset cues are of some importance to localization even in free field.