Analyzer

Blood pressure measurement is performed either invasively by an intra arterial catheter or noninvasively by cuff sphygmomanometry. The invasive method is continuous and accurate but has increased risk; the cuff is safe but less reliable and infrequent. A reliable continuous noninvasive blood pressure measurement is highly desirable. While the possibility of using pulse transit time to monitor blood pressure has previously been investigated, most studies were limited to calculating the correlation of the pulse transit time and blood pressure under rather static conditions. The relationship between the pulse transit time and blood pressure is yet to be clearly identified. This paper focuses on the modeling between the two values and presents results on cases where dramatic variation in blood pressure of the patient was induced by drug administration or surgical stimulation.

Much recent research on the design of natural language lexicons has made use of nonmonotonic inheritance networks as originally developed for general knowledge representation purposes in Artificial Intelligence. DATR is a simple, spartan language for defining nonmonotonic inher-itance networks with path~value equations, one that has been designed specifically for lexical knowledge representation. In keeping with its intendedly minimalist character, it lacks many of the constructs embodied either in general-purpose knowledge representation languages or in contemporary grammar formalisms. The present paper shows that the language is nonetheless sufficiently expressive to represent concisely the structure of lexical information at a variety of levels of linguistic analysis. The paper provides an informal example-based introduction to DATR and to techniques for its use, including finite-state transduction, the encoding of DA Gs and lexical rules, and the representation of ambiguity and ...

The increasing development of miniaturized flow systems and the continuous monitoring of chemical processes require dramatically simplified and cheap flow schemes and instrumentation with large potential for miniaturization and consequent portability. For these purposes, the development of systems based on flow and batch technologies may be a good alternative. Flow-batch analyzers (FBA) have been successfully applied to implement analytical procedures, such as: titrations, sample pre-treatment, analyte addition and screening analysis. In spite of its favourable characteristics, the previously proposed FBA uses peristaltic pumps to propel the fluids and this kind of propulsion presents high cost and large dimension, making unfeasible its miniaturization and portability. To overcome these drawbacks, a low cost, robust, compact and non-propelled by peristaltic pump FBA is proposed. It makes use of a lab-made piston coupled to a mixing chamber and a step motor controlled by a microcomputer. The piston-propelled FBA (PFBA) was applied for automatic preparation of calibration solutions for manganese determination in mineral waters by electrothermal atomic-absorption spectrometry (ET AAS). Comparing the results obtained with two sets of calibration curves (five by manual and five by PFBA preparations), no significant statistical differences at a 95% confidence level were observed by applying the paired t-test. The standard deviation of manual and PFBA procedures were always smaller than 0.2 and 0.1 μg L−1, respectively. By using PFBA it was possible to prepare about 80 calibration solutions per hour.

L'article examine les problemes souleves par l'application des modeles actuels de traitement lexical, developpes pour l'anglais, a des langues agglutinantes telles que le hongrois, ou les mots ont une structure morphologique plus complexe

The increasing development of miniaturized flow systems and the continuous monitoring of chemical processes require dramatically simplified and cheap flow schemes and instrumentation with large potential for miniaturization and consequent portability. For these purposes, the development of systems based on flow and batch technologies may be a good alternative. Flow-batch analyzers (FBA) have been successfully applied to implement analytical procedures, such as: titrations, sample pre-treatment, analyte addition and screening analysis. In spite of its favourable characteristics, the previously proposed FBA uses peristaltic pumps to propel the fluids and this kind of propulsion presents high cost and large dimension, making unfeasible its miniaturization and portability. To overcome these drawbacks, a low cost, robust, compact and non-propelled by peristaltic pump FBA is proposed. It makes use of a lab-made piston coupled to a mixing chamber and a step motor controlled by a microcompu...

A commercially available mercury (Hg) analyzer based on sample combustion, gold amalgamation, and atomic absorption spectrometry (AAS) was evaluated for the direct determination of Hg in composites of human hair and individual samples of horse fur. Results for human hair reference material (NIES No. 13) were within the certified range. Analyses of "blind" samples from an international interlaboratory (n>16) comparison study produced results within 1S.D. of the consensus means. Precision (%R.S.D.) was found to be <5% and total analyses time per sample was <10min. This study demonstrated that analyzers based on combustion-AAS are suitable for wide-scale monitoring of Hg in human hair and animal fur.