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Institutions in France are not yet well prepared to respond to allegations of scientific misconduct. Following a serious allegation in late 1997. INSERM,* the primary organization for medical and health-related research in France, began to reflect on this subject, aided by scientists and jurists. The conclusions have resulted in establishing a procedure to be followed in cases of alleged misconduct, and also in reinforcing the application of good laboratory practices within each laboratory. Guidelines for authorship practices and scientific assessment must also be considered. Even though each institution must remain responsible for responding to allegations of scientific misconduct within its doors, INSERM would like to see national, European, and international co-ordination about the methods of such response. Institut National de la Santé et de la Recherche Médicale (eng. French National Medical Research Institute) is known as INSERM. An earlier version of this paper was presented at a symposium, Scientific Misconduct: An International Perspective, organised by The Medical University of Warsaw, 16 November, 1998.  相似文献   
345.
Auditory streaming and its relevance to attentional processing was examined using event-related brain potentials (ERPs) in situations facilitating perception of one or two streams of sounds. Subjects listened to sequences of brief tones of three different frequencies presented in random order. In evenly spaced (ES) conditions, the three frequencies were equidistant on the musical scale. In clustered, easy (CE) conditions, the attended frequency was distinct, while the middle and extreme distractor tones were clustered together. In clustered, hard (CH) conditions, the attended frequency was clustered with one of the distractors. The subjects pressed a button in response to occasional target tones of longer duration at a prespecified frequency. The subjects were faster and more accurate in CE conditions than they were in ES conditions, and ERP attention effects were enhanced in amplitude in CE conditions. Conversely, the subjects were slower and less accurate in CH conditions and ERP attention effects were delayed in latency and decreased in amplitude. Clustering effects suggest that the processing of stimuli belonging to the attended stream was promoted and the processing of those falling outside the stream was inhibited. The timing and scalp distribution of clustering-related changes in ERPs suggest that clustering modulates early sensory processing in auditory cortex.  相似文献   
346.
The dynamics of many biological systems have recently been attributed to low-dimensional chaos instead of high-dimensional noise, as previously thought. Because biological data are invariably nonstationary, especially when recorded over a long interval, the conventional measures of low-dimensional chaos (e.g., the correlation dimension algorithms) cannot be applied. A new algorithm, the point correction dimension (PD2i) was developed to deal with this fundamental problem. In this article we describe the details of the algorithm and show that the local mean PD2i will accurately track dimension in nonstationary surrogate data.  相似文献   
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A risk group of disruptive boys (N=65) identified in kindergarten was assessed using the same procedures at ages 6–7, 8–9, and 10–11. Criteria used to define the predictors and criterion variable were the same at all assessment times. Severity was addressed by comparing different forms of behaviors, considering the extent of harmful consequences to others (aggressiveness was considered as most harmful, whereas inattention was considered as least harmful), manifestation in multiple settings, and extreme scores (manipulation of cutoff scores). Different assessment strategies (direct observations, ratings) and different informants (trained observers, mothers and teachers) were used. Aggressiveness as rated by mothers was highly stable from age 6 to age 11. Inattention as rated by teachers was stable only from age 6 to age 9, whereas no stability was found for observations of task inappropriate behaviors. Taskinappropriate behaviors observed in mother-child interactions and in multiple settings at age 6–7 were significant predictors of self-reported antisocial behaviors at age 12, but this prediction was not repeated at ages 8–9 and 10–11. Teacher ratings of inattention at ages 6–7 and 8–9 were also significant predictors of self-reported antisocial behaviors at age 12. The predictive power was much lower when mothers' ratings of aggressiveness were used. Findings from the present study support the hypothesis that some antisocial behavior precursors are age dependent, in that they are more characteristic of certain age groups than of others. Implications for the selection of assessment screening procedures are discussed.  相似文献   
348.
A major gap in family therapy, the treatment of children and adults together, is addressed. The literature on the children's participation is reviewed and a model which systematizes their involvement is presented. The full participation of the child necessitates the use of play. To create a context of play without alienating the rest of the family, action-promoting methods are used. These methods are implemented through family activities and role playing, which are followed by discussion. The advantages, the indications, and the contraindications to the use of action in family therapy are presented.  相似文献   
349.
This paper describes a procedure for obtaining conditional accuracy functions(CAFs) from naive observers and a restricted number of trials. The method permits the experimenter to counter the subjects’ tendency to favor accuracy in tasks in which stimulus discrimination is easy. Each time a block of 12 trials contains less than three errors, observers are instructed, by means of a speed-up signal, to respond faster. The subject is continuously informed about her/his effective reaction time. The data show that the desired speed-accuracy tradeoff was obtained within each of the 7 observers. The mean percent error was around 25%.  相似文献   
350.
Auditory event-related brain potentials (ERPs) and reaction times were, analyzed in a selective attention task in which subjects attended to tone pips presented at high rates-Xinterstimulua intervals [ISIs] of 40-200 msec). Subjects responded to infrequent target tones of a specified frequency (250 or 4000 Hz) and location (left or right ear) that were louder than otherwise identical tones presented randomly to the left and right ears. Negative difference (Nd) waves were isolated by subtracting ERPs to tones with no target features from ERPs to the same tones when they shared target location, frequency, or both frequency and location cues. Nd waves began 60-70 msec after tone onset and lasted until 252–350 msec after tone onset, even for tones with single attended cues. The duration of Nd waves exceeded the ISIs between successive tones, implying that several stimuli underwent concurrent analysis. Nd waves associated with frequency processing had scalp distributions different from those associated with location processing, implying that the features were analyzed in distinct cortical areas. Nd waves specific to auditory feature conjunction were isolated. These began at latencies of 110–120 msec, some 30-40 msec after the Nds to single features. The relative timing of the different Nd waves suggests that auditory feaure conjunction begins after a brief parallel analysis of individual features but before feature analysis is complete.  相似文献   
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