Abstracts

Hundred years ago the actual Danish-German border was established following the two Schleswigian plebiscites of 1920. Since then the map of Denmark has not changed its contours, but this does not imply that the borders can be considered to be constant or following a rigid nation state definition. The so-called Rigsfællesskab, the connection between Denmark, Greenland and the Faroe Islands, demonstrates how the dynastic rights of the composite state still defines the borders of the present day realm. The inextricable connection between the nation state and the border towards Germany still gives that border a paramount position in the debate in society and in the rhetoric about borders in general. Still we need to be aware of the existence of other borders and the fact that the process of European integration has changed the meaning and importance of national borders – also in the Danish case.


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A microcomputer-based injection system for investigating the influence of atmospheric pressure on chromatographic response in the analysis of gases B. R. Wybrow and E. J. Greenhow A sample injection system has been developed for investigating injection technique in the gas chromatographic analysis of gases, with particular emphasis on control of the technique in order to measure the influence of atmospheric pressure on chromatographic response.
The injection system is driven by a microcomputer-based sequence controller, which utilizes specially written software and specially built electronic interfacing and pressure measuring equipment.
Automatic injection ofa sample ofgas can be effected at any chosen pressure between vacuum and 25 lpf/in into a three-column chromatographic system which uses 'external to the column oven' flow-switching techniques to separate automatically the gases H2, O2, N2, CO, CH4, CO2, C2H4, and CzH6.
The functions of the control lines of the microcomputer are summarized, electronic equipment is described, and the way in which column switching and backflushing times in the chromatographic analysis have been automatically optimized is briefly explained.
The work shows quantitatively the extent to which variations in atmospheric pressure can influence response when analysing nitrogen using a concentration sensitive detector with helium carrier gas.
Use of the standard 'stopped-flow' technique of injection is shown to minimize the effect of variations in atmospheric pressure on response because the effects of changes in atmospheric pressure at the sample loop and detector on chromatographic response are almost mutually compensatory. Predictions are made concerning the influence of variations in atmospheric pressure on response: (1) for a solely mass-sensitive detector which could suffer significant changes in response, and (2) for a mass-sensitive flame ionization detector which could suffer additionally from the influence of atmospheric pressure on ionization efficiency in a manner dependent on the chromatographic conditions and gases analysed. Un systme d'injection bas sur microordinateur pour l'tude de l'influence de la pression atmosphrique sur la rponse chromatographique dans l'analyse des gaz B. R. Wybrow and E. J. Greenhow Un systme d'injection d'6chantillons a 6t6 dvelopp6 pour l'6tude de la technique d'injection dans l'analyse par chromatographie en phase gazeuse de gaz avec emphase particuli6re sur le contr61e de la technique de fa;on fi mestrer l'influence de la pression atmosphrique sur la r6sponse chromatographique.
Des predictions sont faites concernant l'influence de variations de la pression atmosphrique sur la r6ponse (1) pour des d6tecteurs uniquement sensibles fi la masse qui risquent de souffrir de changement significatifs dans la r6ponse et (2) pour un d6tecteur sensible fi la masse par ionisation en flamme qui, en plus, risque de souffrir de l'influence de la pression atmosph6rique sur l'efficacit6 de ionisation d'une fa;on d6pendant des conditions chromatographiques et des gaz t analyser. Page 136 Use of pattern-recognition display techniques to visualize the data contained in complex data-bases. A case study* M. P. Derde et al.
The object ofthe paper is to illustrate that display and related pattern-recognition techniques permit investigation of multivariate data-sets. This was demonstrated with a practical example: the authentificatio of the geographical origin ofwine. The data-set consisted of 195 different French wines, each was analysed for its amino-acid pattern. The information included in the data was visualized using display methods (principal components analysis--non-linear mapping), as well as supervised methods (linear discriminant analysis) and unsupervised methods (hierarchical clustering). On the basis of the displays obtained it could be concluded that the differentiation of wines according to the origin must be possible by using amino-acid patterns.
On conclut que la discrimination des vins est possible par l'application de ces mbthodes.

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The measurement of serum paracetamol using a discrete analyser R. S. Campbell et al.
The adaptation of a commercially available kit for the measurement of serum 122 paracetamol to a discrete analyser is described. The manual method is a twostage reaction involving the specific enzymatic degradation of paracetamol and the colorimetric determination of the reaction product, p-aminophenol. The limitations imposed by such a two-stage reaction are discussed and experiments to minimize these limitations described.
Results are presented for reagent stability, final colour stability, linearity, carry-over, within-batch and betweenbatch precision and accuracy.
From these results it would appear that the enzymatic paracetamol assay can be adapted to any discrete analyser that may be used in the emergency laboratory.

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Plasma albumin determination on the Cobas Bio centrifugal analyser using bromocresol green J. R. Cowie and G. O. Evans A method is fully described for the determination of plasma albumin using two reagents, and it is based on the binding of albumin to bromocresol green in the presence of citrate buffer. The dye-binding method is compared to an immunoturbidimetric method using the same centrifugal analyser; good agreement between methods is obtained for the range 22-57 g/1. The performance of the method in external quality-assessment schemes is also described.
Dtermination de l'albumine de plasma sur l'analyseur centrifuge Cobas Bio utilisant le vert Bromocrsole J. R. Cowie and G. O. Evans Une m6thode pour la d6termination de l'albumine de plasma est d6crite utilisant deux r6actifs. Cette m6thode se base sur la fixation de l'albumine sur le vert de bromocr6sol dans la pr6sence d'un tampon de citrate. Cette m6thode par fixation de colorant est compar6e fi une m6thode immunoturbidim6trique utilisant le mme analyseur centrifuge; une bonne corr61ation entre les m6thodes est obtenue pour la plage 22 fi 57g/1. La performance de la m6thode pour le contr61e de qualit6 externe est 6galement Page 155 The quality control of measured data* L. Leisztner and P. Barna In two-dimensional analytical measurements analytical information is always biased and of varied standard deviation because of the noise. A method for estimating the standard deviation of random errors of measured signal samples is described. The method was tested by simulating 'noisy' chromatographic measurements on a computer. The generated and the estimated standard deviation of the random errors did not show any significant difference.
Page 157 Analytical performances achieved by the 'Aria II' automatic system in an inter-laboratory survey for triiodothyronine and thyroxine assays A. Pilo et al.