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R Noll

Publications and source records attributed to R Noll.

10 recordsLinked to original sources
PubMed2003

Slag analysis with laser-induced breakdown spectrometry.

Laser-induced breakdown spectrometry (LIBS) has been applied for multi-elemental analysis of slag samples from a steel plant. In order to avoid the time-consuming step of sample preparation, the liquid slag material can be filled in special probes. After cooling of the liquid slag and solidification, the samples can be analyzed with LIBS. Chemical analysis of slag is an essential input parameter used for numerical simulations to control liquid steel processing. The relative variation range of element concentrations in slag samples from steel production can amount to up to 30%. A multivariate calibration model is used to take into account matrix effects caused by these varying concentrations. By optimizing the measuring parameters as well as the calibration models, an agreement between the standard X-ray fluorescence (XRF) analysis and LIBS analysis in terms of the coefficient of determination r2 of 0.99 for the main analytes CaO, SiO2, and Fetot of converter slag samples was achieved. The average repeatability of the LIBS measurement for these elements in terms of the relative standard deviation of the determined concentration is improved to less than 1.0%. With these results, the basis is established for future on-line applications of LIBS in the steel-making industry for slag analysis.

Environmental Monitoring↗
PubMed1999

Substrate specificity of the ileal and the hepatic Na(+)/bile acid cotransporters of the rabbit. I. Transport studies with membrane vesicles and cell lines expressing the cloned transporters.

The substrate specificity of the ileal and the hepatic Na(+)/bile acid cotransporters was determined using brush border membrane vesicles and CHO cell lines permanently expressing the Na(+)/bile acid cotransporters from rabbit ileum or rabbit liver. The hepatic transporter showed a remarkably broad specificity for interaction with cholephilic compounds in contrast to the ileal system. The anion transport inhibitor diisothiocyanostilbene disulfonate (DIDS) is a strong inhibitor of the hepatic Na(+)/bile acid cotransporter, but does not show any affinity to its ileal counterpart. Inhibition studies and uptake measurements with about 40 different bile acid analogues differing in the number, position, and stereochemistry of the hydroxyl groups at the steroid nucleus resulted in clear structure;-activity relationships for the ileal and hepatic bile acid transporters. The affinity to the ileal and hepatic Na(+)/bile acid cotransport systems and the uptake rates by cell lines expressing those transporters as well as rabbit ileal brush border membrane vesicles is primarily determined by the substituents on the steroid nucleus. Two hydroxy groups at position 3, 7, or 12 are optimal whereas the presence of three hydroxy groups decreased affinity. Vicinal hydroxy groups at positions 6 and 7 or a shift of the 7-hydroxy group to the 6-position significantly decreased the affinity to the ileal transporter in contrast to the hepatic system. 6-Hydroxylated bile acid derivatives are preferred substrates of the hepatic Na(+)/bile acid cotransporter. Surprisingly, the 3alpha-hydroxy group being present in all natural bile acids is not essential for high affinity interaction with the ileal and the hepatic bile acid transporter. The 3alpha-hydroxy group seems to be necessary for optimal transport of a bile acid across the hepatocyte canalicular membrane. A modification of bile acids at the 3-position therefore conserves the bile acid character thus determining the 3-position of bile acids as the ideal position for drug targeting strategies using bile acid transport pathways.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1994

New functions of the Drosophila rhomboid gene during embryonic and adult development are revealed by a novel genetic method, enhancer piracy.

Localized expression of the Drosophila rhomboid (rho) gene has been proposed to hyperactivate EGF-Receptor signaling in specific cells during development of the embryo and adult. In this report we use a novel transposon based genetic method, enhancer piracy, to drive ectopic expression of a rho cDNA transgene by endogenous genomic enhancers. Many enhancer piracy transposon-rho insertions cause dominant phenotypes, over half of which cannot be duplicated by ubiquitous expression of rho. Genetic interactions between various dominant enhancer piracy alleles and mutations in the EGF-R/RAS signaling pathway indicate that many of these novel phenotypes result from ectopic activation of EGF-R signaling. Patterned mis-expression of the rho cDNA transgene correlates in several cases with localized dominant enhancer piracy phenotypes. Enhancer piracy lines reveal an unanticipated role for rho in imaginal disc formation and provide the first evidence that mis-expression of rho is sufficient for converting entire intervein sectors into veins. Enhancer piracy may prove to be a general strategy for obtaining dominant alleles of a gene of interest in diverse insects, worms, plants, and potentially in vertebrates such as mice and fish.

Alleles↗
PubMed1989

Multiple personality, dissociation, and C.G. Jung's complex theory.

Jung's contributions to the study of 'dissociation' are outlined here for perhaps the first time. Jung is unique in recognising that the 'dissociability of the psyche' is a fundamental process that extends along the continuum from 'normal' mental functioning to 'abnormal' states. Dissociation is recognised by Jung as a universal and necessary psychic activity for the development of personality through the differentiation of functions. However, when the cohesion of consciousness is shattered by extreme childhood traumata, as it is in the development of multiple personality, this natural differentiation of function is intensified and the dissociative splits between autonomous forces in the psyche become more extreme. This increases the autonomy of these 'splinter psyches' from ego-consciousness and reveals their archetypal core. They then develop into the phenomenon of 'alternate personalities' in multiple personality. In a comparison of the major tenets of the complex theory with recent empirical research on multiple personality, it is demonstrated that essential characteristics of Jung's 'autonomous complexes' are congruent with the phenomenology of the 'alternate personalities' or 'personality states' of this disorder. This underscores the relevance of Jung's complex theory to present understanding of multiple personality. In addition, the phenomenon of multiple personality is, in turn, important for realising the central significance of dissociation in the complex theory and provides an excellent contemporary clinical example of the archetypal ground of the psyche.

Adult↗
PubMed1984

Laminectomy: effects on postoperative technetium and gallium scintigraphy.

Bone scans using Tc-99m diphosphonate were found to become abnormal within 2 weeks after laminectomy in less than half of patients regardless of the extent of the operation. The degree of new uptake equaled that of the sacroiliac joints in only one of 19 patients with a normal preoperative scan. However, the Ga-67 citrate scan usually became abnormal (89%) postoperatively. Thus the Tc-99m bone scan may be helpful in detecting postoperative infection.

Diphosphonates↗
PubMedDate not supplied

What has really been learned about shamanism?

Within anthropology, investigations of shamans and their altered states of consciousness have followed some of the prescriptive problems inherited from the discipline of psychology, coloring the assumptions and perspectives of students of shamanism. These inherited problems include the following: conscious/volitional versus unconscious/involuntary mentalisms; contentual objectivism versus contentual subjectivism; environmentalism versus nativism; monopsychism versus polypsychism; mechanism versus vitalism; and quantitativism versus qualitativism. Although the polemics of anthropological studies of shamanism have reflected these prescriptive perspectives, this has not inhibited the acquisition of new knowledge about shamanism. Nonetheless, a resolution of these problems is lacking due to insufficient data.

Culture↗