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Вводится продолжение функцио налов с пространства на , гдеc kb k. Такие функционалы ха рактеризуются в терм инах их роста на бесконечнос ти. Исследуется также пр одолжение функциона лов в пространстве мульти пликаторов. Накладываются разли чные условия роста го ломорфных функций в трубчатых областях и исследует ся рост соответствую щих специальных функций.

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Summary

Galantamine hydrobromide was subjected to oxidative stress degradation using hydrogen peroxide and analyzed as per the chromatographic conditions described in European Pharmacopoeia. The drug showed considerable degradation at ambient temperature resulting in the formation of two degradation products at relative retention times (RRTs) 0.63 and 2.52. The minor degradant at RRT 0.63 was identified as galantamine N-oxide. The principal degradant formed at RRT 2.52 was found to be unknown and has not been reported previously. The unknown impurity was identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) followed by isolation using semi-preparative high-performance liquid chromatography (HPLC). The isolated impurity was characterized using one-dimensional, two-dimensional nuclear magnetic resonance spectroscopy (1D and 2D NMR) and elemental analysis (EA). The principal degradant was found to be formed due to the generation of bromine and subsequent attack on the aromatic ring via in situ reaction between hydrogen bromide and hydrogen peroxide. The unknown impurity was characterized as (4aS,6R,8aS)-5,6,9,10,11,12-hexahydro-1-bromo-3-methoxy-11-methyl-4aH-[1]benzofuro [3a,3,2-ef] [2] benzazepin-6-ol.

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Acta Physiologica Hungarica
Authors: K. Tarhzaoui, A. Behar, R. Lestrade, C. Hort-Legrand, F. Cohen-Boulakia, and Paul Valensi

In rats with diabetes induced at weaning, pathological examinations have shown that the reduction of myelin thickness occurs earlier than axon size reduction. The aim of this study was to provide a detailed description of neurophysiological changes during nerve growth and maturation in rats with streptozotocin-induced diabetes in prepubertal stage. Five-day male Wistar rats received an injection of streptozotocin. Motor and sensory conduction velocities increased until 6.5 months in diabetic and control rats and at this age it became lower in diabetic rats. In diabetic rats, the amplitudes of the compound motor action potentials (CMAP) were lower by the 3 months and did not increase later. The amplitudes and areas of sensory action potentials (SNAP) increased until 9 months in both groups. SNAP duration decreased with ageing. Sensory peak 1 and peak 2 latencies became longer from 6.5 to 9 months in diabetic rats, with a longer latency difference between the 2 sensory peaks by 4 months. At 3 and 4 months of age, peak 1 and peak 2 latencies correlated with SNAP amplitude and duration in control rats but not in diabetic rats. In conclusion, in rats with early induced diabetes, the earliest electrophysiological impairments consist of lower CMAP amplitudes, and longer difference between latencies of sensory peaks 1 and 2. These sequential neurophysiological changes should be considered when testing new therapeutic approaches in diabetic neuropathy.

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Journal of Thermal Analysis and Calorimetry
Authors: R. Hilfiker, J. Berghausen, F. Blatter, A. Burkhard, S. De Paul, B. Freiermuth, A. Geoffroy, U. Hofmeier, C. Marcolli, B. Siebenhaar, M. Szelagiewicz, A. Vit, and M. von Raumer

Abstract  

Crystal structure (polymorphism) as well as crystal shape (morphology) and size have a huge practical and commercial impact on active substances all the way from research to manufacture of the final product. For an optimal development process, it is important to have an integrated approach to these issues ranging from a systematic polymorphism screening to a controlled scale-up of the crystallization process. The polymorphism program has to be tailored according to the development stage. Particularly suitable for an early development stage is a high-throughput polymorphism screening, which is the basis for a more thorough investigation if the product proceeds further in development. Such a comprehensive polymorphism investigation involves further crystallization experiments and extensive physicochemical characterization of the various forms. In this article the high-throughput polymorphism screening method that we have developed is described. Using carbamazepine as an example, the power of this high-throughput polymorphism screening system is demonstrated. Not only were all published forms found, but also new forms were identified. In the second part of the article, important considerations for crystallization optimization are discussed, again using the example of carbamazepine.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Paul, A. Valenta, I. Ahmad, D. Berkovits, C. Bordeanu, S. Ghelberg, Y. Hashimoto, A. Hershkowitz, S. Jiang, T. Nakanishi, and K. Sakamoto

Abstract  

We report here a search for the “live” 244Pu in 1 kg deep-sea dry sediment collected in 1992 in the North Pacific. After a 546 day alpha-counting of a Pu fraction chemically separated from the alkaline-fused sediment sample at Kanazawa University, AMS analysis was performed at Hebrew University and Weizmann Institute. Only one count of 244Pu with no background ions was detected, indicating no excess over the expected stratospheric man-made fallout. A limit of 0.2 atoms of 244Pu cm−2·y−1 for extra terrestrial deposition was set under reasonable assumptions and it was then concluded from this result and the available data on interstellar medium (ISM) that the abundance of 244Pu in the ISM is less than 2·10−11 g 244Pu (g·ISM)−1. Implications of the present result are discussed.

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