The mass spectra of griseofulvin analogues. Characteristic fragmentation processes in the mass spectra of spiro-cyclohexenones and spiro-cyclohexanones containing the griseofulvin skeleton

The mass spectra of a number of griseofulvin analogues have been examined and the fragmentations, which are characteristic of the basic skeleton of the molecule, have been determined. In all of the different structural types examined, the ring cleavages which predominate are found tol occur by fission of one or more of the bonds attached to the spiro carbon atom. The degree of unsaturation in the spiro-cyclohexane ring system is found to controll the type of fragmentation which occurs and the type of ring system which is present can therefore be identified by its mass spectrum.     

Heritability of Stroop and flanker performance in 12-year old children

Background  

There is great interest in appropriate phenotypes that serve as indicator of genetically transmitted frontal (dys)function, such as ADHD. Here we investigate the ability to deal with response conflict, and we ask to what extent performance variation on response interference tasks is caused by genetic variation. We tested a large sample of 12-year old monozygotic and dizygotic twins on two well-known and closely related response interference tasks; the color Stroop task and the Eriksen flanker task. Using structural equation modelling we assessed the heritability of several performance indices derived from those tasks.     

The contribution of high frequencies to human brain activity underlying horizontal localization of natural spatial sounds

Background  

In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment.     

Management Planning and Control in Multi-Branch Banking

This paper describes a model developed for a British bank to assist management in establishing branch goals, evaluating performance and planning new locations. Econometric methods are used to produce a set of equations which effectively predicts the main dimensions of branch performance.