Gender-related differences on the College Board's Advanced Placement and Achievement tests, 1982–1992.

This study explored gender-related differences in participation in and scores on the College Board's Advanced Placement Program and Achievement examinations. In both sets of tests, the numbers of male and female high school students were unequal for several subject areas. The French, Spanish, and Modern Hebrew examinations attracted many more female than male students, whereas many more male than female students took the Physics, Chemistry, and Computer Science examinations. There was little change in most of the patterns of enrollment from 1982 through 1992. Male students had moderately higher scores on the Physics, Chemistry, and Computer Science tests, whereas female students had a slight advantage on some of the language examinations. Although the patterns of gender-related score differences were stable, there were some indications that gender differences are narrowing, especially in the areas of American history and computer science. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The design of technical artifacts with regard to work experience: The development of an experience-based documentation system for maintenance workers

The German discussion about experience-guided work has led to the question of how work experience can be regarded within the process of designing technical artifacts. This paper offers a solution for the area of skilled maintenance work. Some considerations about the nature of experience and about the problems skilled workers have in aquiring work competences within computer aided production environments are introduced in order to illustrate the design philosophy: A decision-support-system is described which stimulates workplace learning by enabling previous and present users of the system, including maintenance staff and shop floor workers, to exchange and build on experience.     

The hepatic interleukin-6 receptor. Studies on its structure and regulation by phorbol 12-myristate 13-acetate-dexamethasone

Recombinant human 125I-interleukin-6 (IL-6) was cross-linked with the homobifunctional reagent disuccinimidyl suberate to human hepatoma cells (HepG2). Three recombinant human 125I-IL-6-containing complexes of apparent molecular masses of 100, 120, and 200 kDa were immunoprecipitated with specific antibodies to human IL-6 or to the 80-kDa IL-6 receptor subunit. We show by immunoprecipitation, peptide mapping, and by the use of a cleavable heterobifunctional cross-linker (Denny-Jaffe reagent) that different polypeptides are involved in the formation of the 100- and 120-kDa IL-6-containing complexes. The molecular compositions of the 100- and 120-kDa cross-linked complexes were identified. The 100-kDa complex consisted of one ligand and one IL-6 receptor subunit, glycoprotein 80 (gp80), whereas the 120-kDa complex was found to be composed of one ligand and a polypeptide which was immunoprecipitable with the monoclonal antibody AM64 directed against gp130. Exposure of HepG2 cells to phorbol 12-myristate 13-acetate (PMA) or PMA-dexamethasone led to an increase in the 80-kDa IL-6 receptor mRNA and functional receptor protein. Whereas treatment of HepG2 cells with PMA led to an increase in the formation of gp80.gp130.IL-6 complexes determined by cross-linking, no corresponding increase in high affinity binding sites was found. The existence of a third IL-6 receptor subunit present in limiting amounts on HepG2 cells is proposed to explain this discrepancy. Evidence is presented that the 80-kDa IL-6 receptor up-regulation by PMA-dexamethasone is caused by the depletion of protein kinase C since the protein kinase C inhibitor staurosporine mimics the effect of PMA-dexamethasone.     

Finite element approximation to buoyancy-driven flows with cyclic boundary conditions

The calculation of the total normal forces and the dynamic pressure on a rectangular wing at different rocket velocities is presented. Two programs for computer-aided design of rocket wings were developed. Variations of velocity and air temperature modify the expected performance curves.     

Untersuchungen über den Kohlenmonoxydzerfall und seine katalytische Vergiftung

Untersuchung über den Einfluß von Schwefelwasserstoffzusätzen zu Kohlenmonoxyd und gichtgasähnlichen Gasgemischen auf den Kohlenmonoxydzerfall an Gichtstaub und reinem Eisen(III)-oxyd. Erörterung der Analysenverfahren. Diskontinuierliche Vergiftungsversuche. Betriebsversuche an kleinen Rekuperatoren. Versuche an feuerfesten Steinen.     

Biotransformation of glycidol by the unspecific wax ester synthase/acyl‐CoA:diacylglycerol acyltransferase of Acinetobacter baylyi ADP1

Glycidol was biologically derivatized by the unspecific wax ester synthase/acyl coenzyme A (acyl‐CoA): diacylglycerol acyltransferase (WS/DGAT) from Acinetobacter baylyi ADP1 into glycidyl acyl ester. Catalysis of in vitro conversion of glycidol to glycidyl acyl ester by the WS/DGAT from A. baylyi was verified by (i) a radiometric assay, (ii) thin‐layer chromatography and (iii) also by ESI‐MS. A specific activity of 50 nmol·mg^–1·min^–1 was obtained when 10 mM glycidol and 5 µM palmitoyl‐CoA were used. In vivo synthesized glycidyl acyl esters in recombinant E. coli were detected and quantified by staining with the epoxide‐specific reagent 4‐(4‐nitrobenzyl)‐pyridine. Of glycidyl acyl esters, 1.5 mg/L was obtained from the culture in the presence of 10 mM glycidol and 10 mM oleate.