1H-, 13C- und 15N-NMR-Untersuchungen an substituierten Thiadiazolen

¹H-, ¹³C- and ¹⁵N-N.M.R.-Studies on Substituted Thiadiazoles A number of substituted 1,2,4-thiadiazoles, unlabelled and ¹⁵N-labelled, were studied by ¹H-, ¹³C- and ¹⁵N- n.m.r. spectroscopy. The obtained n.m.r. data, especially the nitrogen-15 chemical shifts and the ¹⁵N-¹H and ¹⁵N-¹³C coupling constants allow to distinguish between isomeric forms and to determine the correct structure of each compound. So it was possible to come to conclusions about the formation mechanism of the investigated compounds.     

Characterization of dyes and other pollutants in the effluent of a textile company by LC/NMR and LC/MS

LC/NMR and LC/MS (the latter technique in the MSn mode) were used to characterize the organic constituents of industrial wastewater with emphasis on polar, nonvolatile compounds. In the effluent of a textile company, various compounds such as anthraquinone-type dyes and their byproducts, a fluorescent brightener, a byproduct from polyester production, and auxiliaries such as anionic and nonionic surfactants and their degradation products were identified. It is shown that the combined use of both hyphenated techniques provides complementary structural information. If applied under comparable chromatographic conditions, they are well-suited for the nontarget analysis.     

Complications of cardiac hydatid cyst. 2 cases

BACKGROUND: Cardiac localization of hydatiosis is uncommon, involving 0.5 to 2% of all cases. CASE REPORTS: The first patient was a 15 year old adolescent whose cardiac hydatidosis was revealed by tamponade. The second case was discovered in a 28-year-old woman without cardiac signs who was explored for allergy manifestations with fever, urticaria and joint point. Both patients underwent surgery. Eighteen months after the operation, the second patient developed hemiplegia leading to the discovery of multi-organ localizations (brain, spleen, kidney) which were not evidenced at the initial work-up. The neurological deficit and brain cysts regress with albendazole treatment. DISCUSSION: The risk of rupture of the cardiac hydatic cyst requires rapid surgical cure. Medical treatments are discussed. Anti-hydatic drugs can be used alone in case of a contraindication for surgery. In other patients they are given during the perioperatie period and for a prolonged period after surgery.     

Isomorphic Representations and Well-Formedness of Engineering Systems

When representing the elements of different engineering systems as vertices and edges of a mathematical graph, the well-formedness of the topology of the graph, and hence the topology of the engineering system, can be explicitly computed. This enables checking the well-formedness of the engineering system before investing the effort needed for a complete analysis. This method is demonstrated in the paper for the following fields: trusses, dynamic mass-spring-damper oscillator systems and planetary gear systems. The approach facilitates achieving rapid design, correct first time, which is an important aim of modern design computation.     

Comparative measurements of highly irradiated n-in-p and p-in-n 3D silicon strip detectors

Silicon detectors in 3D technology are a candidate for applications in environments requiring an extreme radiation hardness, as in the innermost layers of the detectors at the proposed High-Luminosity LHC. In 3D detectors, the electrodes are made of columns etched into the silicon perpendicular to the surface. This leads to higher electric fields, a smaller depletion voltage and a reduced trapping probability of the charge carriers compared to standard planar detectors. In this article, the signal and the noise of irradiated n-in-p and p-in-n 3D silicon strip detectors are compared. The devices under test have been irradiated up to a fluence of 2×10¹⁶ 1 MeV neutron equivalent particles per square centimetre (n_eq/cm²), which corresponds to the fluence expected for the inner pixel detector layers at the High-Luminosity LHC. A relative charge collection efficiency of approximately 70% was obtained even after the highest irradiation fluence with both detector types. The influence of different temperatures on the signal and the noise is investigated and results of annealing measurements are reported.     

Evidence for essential arginine residues at the active sites of maize branching enzymes

Alignment of 23 branching enzyme (BE) amino acid sequences from various species showed conservation of two arginine residues. Phenylglyoxal (PGO) was used to investigate the involvement of arginine residues of maize BEI and BEII in catalysis. BE was significantly inactivated by PGO in triethanolamine buffer at pH 8.5. The inactivation followed a time- and concentration-dependent manner and showed pseudo first-order kinetics. Slopes of 0.73 (BEI) and 1.05 (BEII) were obtained from double log plots of the observed rates of inactivation against the concentrations of PGO, suggesting that loss of BE activity results from as few as one arginine residue modified by PGO. BE inactivation was positively correlated with [14C]PGO incorporation into BE protein and was considerably protected by amylose and/or amylopectin, suggesting that the modified arginine residue may be involved in substrate binding or located near the substrate-binding sites of maize branching enzymes I and II.     

Functional analysis of conserved histidines in ADP-glucose pyrophosphorylase from Escherichia coli

A technique is described in which most, if not all, cardiac operations may be performed through a standard small incision. A midline, lower half sternotomy is used. This provides traditional exposure of the heart and allows the surgeon to directly visualize the operating field and use familiar instruments. The complete spectrum of coronary revascularization and cardiac valve operations has been performed through this less-invasive incision.