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Directly coupled 600-MHz [HPLC.sup.-1]H NMR was used for the first time to investigate the potential of this technique in the screening of tropical plants for naphthylisoquinoline alkaloids. A leaf extract of Ancistrocladus guineensis was analyzed both in the on-flow mode and in the stop-flow mode using reversed-phase isocratic and gradient compositions of acetonitrile and [D.sub.2]O on a [C.sub.18] column. On-flow experiments proved the occurrence of naphthylisoquinoline alkaloids in the extract Stop-flow measurements confirmed the presence of ancistrotectorine and two new diastereomeric alkaloids. With 2D TOCSY experiments performed in the stop-flow mode, it was possible to deduce their constitution. For the elucidation of the relative configuration, a 2D HPLC-NMR ROESY experiment was developed by supplying a conventional ROESY sequence with a double presaturation block during the relaxation delay. Application of the optimized ROESY method confirmed the constitution of the two new alkaloids and showed relative cis and trans configurations of the methyl groups at the isoquinoline moieties. These results underline the value of this approach for a rapid and reliable phytochemical screening of plant extracts for naphthylisoquinoline alkaloids. The identification of known alkaloids as well as the characterization of new structures is possible without any purification step. The results were used as the basic information for the selective isolation of the new structures.

Convex cones play an important role in nonlinear analysis and optimization theory. In particular, specific normal cones and tangent cones are known to be convex cones, and it is a crucial fact that they are useful geometric objects for describing optimality conditions. As important applications (especially, in the fields of optimal control with PDE constraints, risk theory, duality theory, vector optimization, and order theory) show, there are many examples of convex cones with an empty (topological as well as algebraic) interior. In such situations, generalized interiority notions can be useful. In this article, we present new representations and properties of the relative algebraic interior (also known as intrinsic core) of relatively solid, convex cones in real linear spaces (which are not necessarily endowed with a topology) of both finite and infinite dimension. For proving our main results, we are using new separation theorems where relatively solid, convex sets (cones) are involved. For the intrinsic core of the dual cone of a relatively solid, convex cone, we also state new representations that involve the lineality space of the given convex cone. To emphasize the importance of the derived results, some applications in vector optimization are given. [ABSTRACT FROM AUTHOR]

Bühnenpräsenz, guter Stimmansatz und Begeisterung fürs Spielen: Können Lehrende diese Kompetenzen von Kabarettisten erlernen? Gerlinde Kempendorff-Hoene, selbst Lehrerin und Bühnenkünstlerin, sagt „Ja!“. In ihrem Dissertationswerk Lehrer und Kabarettisten gibt sie gleich zu Beginn einen kurzen Überblick zur Beziehung zwischen Bildung und Bühne, zeigt Parallelen von Lehrer/Schüler/Klassenzimmer zu Kabarettist/Publikum/Bühne auf. Kabarettistische Kunst erzeugt gelungene Kommunikation, die ihrerseits lebendige Sphäre für Lernprozesse eines Publikums ist. (...) Kabarettisten und Pädagogen (...) sind beide Kommunikatoren mit dem Ziel, eigensinnige Lernprozesse ihrer Mitmenschen anzuregen. (147) Die Autorin macht bereits auf den ersten Seiten deutlich, dass in der Lehrerausbildung (Lehrer werden hier stellvertretend für Menschen in Führungspositionen genannt) essentielle Grundlagen der Kommunikation verloren gehen: vor allem in Bezug auf die Stimme, die Präsenz und die Kommunikationskultur. Es ist nicht neu, dass ästhetische Erlebnisse gepaart mit Freude großen Einfluss auf die Aufwertung der Persönlichkeit haben und auch „der Erfolg (...) eine zuverlässige Droge für die Motivation“ ist „neue Herausforderungen anzunehmen.“(43). Die Autorin versucht durch den Vergleich Lehrer/Kabarettist die ästhetischen Erlebnisse von Schülern zu steigern, indem Lehrer didaktisches und methodisches Handwerkszeug erlernen. Gerlinde Kempendorff-Hoene konzentriert sich auf drei Aspekte: (43) Von Schiller bis zu den Veröffentlichungen in Zeitungen und Zeitschriften heute – überall wird die Wichtigkeit, Dringlichkeit, ja ...

Object: The authors undertook a retrospective analysis of the incidence and time course of pituitary insufficiency following gamma knife radiosurgery (GKS) for pituitary adenomas., Methods: Pituitary adenomas in 92 patients were analyzed. There were 61 hormonally inactive tumors, 18 prolactinomas, and nine somatotropic and four adrenocorticotropic adenomas. The mean tumor volume was 3.8 cm3 (range 0.2-14.6 cm3). The mean prescription dose was 15 Gy. The mean prescription isodose was 50.7%. The mean follow-up time was 4.6 years (range 1.2-10 years). The following new or deteriorating insufficiencies that did not require treatment were recorded for the different pituitary axes: follicle-stimulating hormone (FSH)/ luteinizing hormone (LH) 19 (20.6%), thyroid-stimulating hormone (TSH) 32 (34.8%), adrenocorticotropic hormone (ACTH) 10 (10.9%), and growth hormone (GH) 26 (28.3%). For new insufficiencies or deterioration requiring replacement therapy, the figures were as follows: FSH/LH 20 (21.7%), TSH 22 (23.9%), ACTH eight (8.7%), and GH 12 (13%). Spot dosimetry was performed in 59 patients in the hypothalamic region, the pituitary gland, and pituitary stalk. The pituitary stalks in patients with deterioration of pituitary function received a statistically higher dosage of radiation, 7.7 +/- 3.7 Gy compared with 5.5 +/- 3 Gy (p = 0.03)., Conclusions: The function of the residual normal pituitary gland is less affected following GKS of pituitary adenomas than after fractionated radiotherapy. Nonetheless, increased attention needs to be exercised to reduce the dose to the stalk and pituitary gland to minimize the incidence of these complications.