Nicolas Bourbaki and the concept of mathematical structure

In the present article two possible meanings of the term mathematical structure are discussed: a formal and a nonformal one. It is claimed that contemporary mathematics is structural only in the nonformal sense of the term. Bourbaki's definition of structure is presented as one among several attempts to elucidate the meaning of that nonformal idea by developing a formal theory which allegedly accounts for it. It is shown that Bourbaki's concept of structure was, from a mathematical point of view, a superfluous undertaking. This is done by analyzing the role played by the concept, in the first place, within Bourbaki's own mathematical output. Likewise, the interaction between Bourbaki's work and the first stages of category theory is analyzed, on the basis of both published texts and personal documents.Several persons have read and criticized earlier drafts of this paper. I thank them all for forcing me to formulate my ideas more simply and convincingly. Special thanks are due to Professors Pierre Cartier (Bures-sur-Yvette), Giorgio Israel (Rome), and Andrée C. Ehresmann (Amiens) for stimulating and illuminating conversations.     

Letter to the editor,Schools on Islands,a journal as a Ferry

In an electronic brainstorming session, experts and users of methods for multi-criteria decision analysis discussed editorial policies for a journal which is confronted with the conflicts between isolated schools of thought. The present paper describes the session and highlights how experts in multi-criteria decision analysis view the applications of their own methods on their own decision problems.     

The predictive validity of the Zung Index of Potential Suicide

Examined the predictive validity of the Zung Index of Potential Suicide. Subjects hospitalized for a suicide attempt were followed up 6 months later. In agreement with earlier studies, the IPS clinical scale was related to suicidal ideation and prior attempting at the time of admission. However, it was not related to further suicidal behavior or ideation at the 6-month followup. It is concluded that the scale lacks predictive validity and its use for assigning suicidal risk is not justified.     

Action and reaction elements as performance-modifying components of computer use in clinical psychology

Application of computerized equipment in psychodiagnosis and cognitive training entails novel methodical aspects which relate to design of operator and response controls as well as to the test configuration. Some of these aspects are discussed.     

A technique for chronic recording of systemic arterial blood pressure in the unrestrained rat

A technique is described for the chronic recording of systematic arterial blood pressure, respiration, and heart rate in the unrestrained rat. The surgical implantation and anchoring procedures described are compatible with the delivery of noxious electric shock and/or rewarding intracranial brain stimulation as reinforcement. Data on catheter patency are analyzed in 65 rats participating in a variety of experiments on the instrumental and classical conditioning of blood pressure responses. The results indicate that it is difficult to maintain satisfactory catheter performance beyond 2 weeks.     

PROCTOR: An on-line student evaluation and monitoring system for use with PSI format courses

PROCTOR, an on-line interactive system for student evaluation and monitoring in courses employing the PSI format, is described. This system involves a tester module that assumes many of the routine managerial duties traditionally assigned to the student proctor, such as quiz administration and scoring, performance feedback, and complete record keeping. Also, PROCTOR includes a multipurpose editor that allows an instructor to enter, examine, or modify any information in the disk files accessed by the tester. Factors related to the implementation and use of this system are considered, and its advantages for management, quality control, and staffing in PSI courses are discussed.     

The detection of anisochrony in monaural and interaural sound sequences

Nakao and Axelrod (1976) and van Noorden (1975) showed that the threshold for discriminating an anisochronous duple rhythm (a series of clicks with a temporal offset on every other one) from an isochronous rhythm (no offset) is poorer when the clicks are presented alternately to the two ears than when they are presented to the same ears. Van Noorden reported that the difference between the thresholds in the alternating and nonalternating conditions varied with the tempo of the sequence. Nakao and Axelrod found invariance of this threshold difference with sequence speed. According to our quantification of temporal processing of interaural sequences, the latter result should be expected. We carried out five psychophysical experiments to establish interaural and monaural discrimination between isochronous and anisochronous rhythms. Across experiments, base time intervals of 60–720 msec were spanned. The main result was that we replicated the poorer discrimination for interaural sequences. This deterioration in discrimination was the same for all sequence speeds. It was also the case that the thresholds were almost constant up to a sound repetition rate of about 3 per second, but increased linearly with slower rates. This result supports evidence in the literature that temporal processing of sequences faster than about 3–4 sounds per second differs from temporal processing of slower sequences.