Parallel quicksort

A parallel version of quicksort on a CRCW PRAM is developed. The algorithm uses n processors and a linear space to sort n keys in the expected time O(log n) with large probability.     

Volatile organo-halogen trace analysis in beverages by thin-layer headspace enrichment and electron-capture gas-chromatography

Applicability of thin-layer headspace (TLHS) procedure giving an aqueous concentrate and also classical purge and trap (PT) in off-line mode to isolate and enrich volatile organohalogen compounds in common beverages was tested. Both enrichment tech-niques were used in combination with gas chromatography – electron capture detection (GC-ECD). TLHS, combined with direct aqueous injection (DAI)-GC-ECD, proved applicable in the determination of volatile organohalogen compounds in all studied beverages, while the PT in a version with no preliminary sample pre-treatment was of limited applicability. Detection limits of the TLHS-based procedure were in the order of 1 ppt. Content of volatile organohalogen compounds in a number of beverages available on the Polish market including mineral waters, beers, juices, carbonated and non-carbonated soft drinks, etc. was determined by means of TLHS-DAI-GC-ECD.     

Investigation and Elaboration of Methods of Multicolor Optical Thermometry

The various complex mathematical transformations previously proposed for eliminating methodological errors of multicolor radiation pyrometry are mainly reduced to the determination of such combinations of wavelengths or corrections of registered brightness for the spectral distribution of the radiating capacity of the object being thermometered at which its equivalent radiating capacity is equal to unity. Mathematical formulas of the determining parameters of multicolor pyrometry of radiation have been obtained. Engineering techniques for calculating the critical values of the determining and adjustable parameters at which the application of multicolor optical thermometry is excluded because of large errors have been developed. Algorithms of a priori and a posteriori calibration systems of multicolor pyrometry of radiation of objects with practically any spectral distribution of the radiating capacity are proposed.     

Significance of tissue polypeptide specific antigen (TPS) in diagnosis and monitoring of treatment in ovarian cancer

BACKGROUND AND STUDY AIMS: It has recently been reported that in developed countries gastric outlet obstruction now predicts gastric malignancy. The aim of this study was to find out if this is the case in a developing country like India. PATIENTS AND METHODS: Seventy-four patients with gastric outlet obstruction underwent upper gastrointestinal endoscopy and biopsy specimens were obtained from any suspicious looking lesions or from the most distal point at which the endoscope could be positioned. RESULTS: In 56 patients (76%) the cause of the gastric outlet obstruction was malignant. On clinical and endoscopic appearance three patients were wrongly diagnosed as having malignancy when the cause, on endoscopic biopsy, was benign (tuberculosis n = 2, and immunoproliferative small intestinal disease n = 1). Twelve of the 18 patients with benign gastric outlet obstruction were managed conservatively with drugs and endoscopic balloon dilatation. CONCLUSION: Even in a developing country like India, malignancy is the commonest cause of gastric outlet obstruction and endoscopic biopsy specimens should be obtained in all patients with gastric outlet obstruction because the occasional benign lesions can be managed conservatively.     

Interpretation of long-chain structure from dilute solution properties of ultrahigh molecular weight polymers

Summary Systematic studies on solution properties of ultrahigh molecular weight polymers showed the existence of some special features as compared to usual length polymers. The paper discusses the possible appearance of branched structures in the polymerization process, structures able to influence the mentioned features. From experimental data on poly(methyl methacrylate), poly(butyl methacrylate) and polyacrylonitrile it appears that branching can be excluded, and the very high molecular weight domain considered may be responsible for the modifications observed in the molecular weight dependences on 2>, A₂ or [].     

A conformance test suite for TTCN-3 tools

With more than 10 years of maturing through industrial use and standardization, the Testing and Test Control Notation (TTCN-3) has become a widely used technology that many businesses depend upon for ensuring their product quality. With the rising number of supporters and tools, the demand for a means to assess the standards compliance of TTCN-3 tools has increased. In this article, we describe the motivation, approach, methodology, and results of the still ongoing project to develop a standardized conformance test suite for TTCN-3 tools. We discuss the challenges involved in creating such a test suite, the way to deal with imposed resource limitations of the project, and where we think the effort is heading.     

Macromolecular anchoring layers for polymer grafting: comparative study

Comparative study of efficiency of macromolecular anchoring layers in the grafting of end-functionalized polymers to a surface was conducted. Poly(glycidyl methacrylate) (PGMA) and epoxydized polybutadienes (EPB) were utilized as the primary anchoring films. Amount of the epoxy moieties introduced to the surface was varied via thickness of the modifying polymer layer or amount of epoxy groups in the polymer backbone. Comparison between the grafting of polystyrene and poly(ethylene glycol) to the various macromolecular anchoring layers indicated that grafting ability of a layer was mostly governed by thickness of the interpenetration zone between the two polymers (anchoring and being grafted). In case of low level of the interpenetration, only functional groups at the periphery of the primary polymer layer were available for the grafting. Then, amount of grafted polymer did not increase with total number of epoxy groups in the anchoring film. However, as the thickness of the interpenetration zone increased, higher amount of the functional groups become available for the grafting.