Neue Triterpens?uren der Weintraubenschale

Zusammenfassung Die Cuticula von Traubenschalen enthält neben Oleanolsäure noch 3-Oxo-olean-12-en28-säure, 3-Hydroxi-olean-12-en-28-aldehyd, 3,29-Dihydroxi-olean-12-en-28-säure sowie zwei bisher unbekannte Triterpensäuren. Ihre Strukturen werden durch spektroskopische Daten als 16-Hydroxi-3-oxo-olean-12-en-28-säure und 16-Hydroxi-3-oxo-oleana-1,12-dien-28-säure belegt.

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New triterpenic acids from the peel of grapes

Summary The grape-cuticle contains beside oleanolic acid, 3-oxo-olean-12-en-28-oic acid, 3-hydroxy-olean-12-en-28-aldehyde, 3,29-dihydroxy-olean-12-en-28-oic acid, and two yet hitherto unknown triterpenic acids. Their structures have been elucidated by spectroscopic methods to be l6-hydroxy-3-oxo-olean-12-en-28-oic acid and 16-hydroxy-3-oxo-oleana-1,12-dien-28-oic acid.

     

Die Mikroflora des Sauerteiges

Zusammenfassung Es wurden Ermittlungen über das Vitaminbedürfnis der an der Sauerteiggdrung beteiligten Milchsäurebakterien der UntergattungenThermobacterium, Streptobacterium andBetabacterium angestellt.Von den überprüften Sauerteigbakterien waren 54 Stämme aus sog. Reinzuchtsauerteigen und 49 Stämme aus Sauerteigen isoliert worden. Alle Sauerteigbakterien erwiesen sich biotin-, vitamin B₆-, vitamin B₁₂-, pyridoxamin- und pyridoxalautotroph. Ohne Ausnahme besteht bei den Sauerteigbakterien ein Bedürfnis an Pantothensäure und Nicotinsäure. Die Bedürftigkeit der Sauerteigbakterien an Folsäure, Vitamin B₂ und Vitamin B₁ ist von Art zu Art wechselnd.Das Vitaminbedürfnis der verschiedenen Gruppen von Sauerteigbakterien steht weitgehend in Übereinstimmung mit dem Bedürfnis der jeweils zum Vergleich herangezogenen Milchsäurebakterien definierter Art. Die Befunde geben somit eine Bestätigung der anhand des Zuckerspektrums vorgenommenen Zuordnung der Sauerteigbakterien zu den ArtenLactobacillus aeidophilus, L. casei, L. plantarum, L. fareiminis, L. brevis, L. brevis var. lindneri, L. fermentum undL. fructivorans.

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The microflora of sourdoughV. Communication: The vitamin requirement of lactic acid bacteria (Genus lactobacillus Beijerinck) of sourdough starter and sourdough

Summary Research was carried out on the vitamin requirements of lactic acid bacteria of the subgeneraThermobacterium, Streptobacterium andBetabacterium, which have a part in the sourdough fermentation. Of the investigated sourdough bacteria 54 strains were isolated from the Reinzuchtsauer (a starter culture) and 49 strains from sourdough. All sourdough bacteria were biotin-, vitamin B₆-, vitamin B₁₂-, pyridoxamine-and pyridoxal-autotroph. All sourdough bacteria showed a requirement for pantothenic acid and nicotinic acid. The requirement of sourdough bacteria for folic acid, vitamin B₂ and vitamin B₁ varied from species to species. The vitamin requirements of the different species of sourdough bacteria mostly agree with the requirements of reference strains of lactic acid bacteria (ATCC-strains, DSM-strains) with which they were compared. The results are therefore a confirmation for having assigned the sourdough bacteria from their sugar fermentation reactions to the speciesLactobacillus acidophilus, L. casei, L. plantarum, L. farciminis, L. brevis, L. fermentum, L. fructivorans andL. brevis var. lindneri.

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Nr. 4470 der Veröffentlichungen der Bundesforschungsanstalt für Getreide- und Kartoffelverarbeitung, Detmold

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Diese Untersuchungen wurden ermöglicht durch eine finanzielle Förderung seitens des Bundesministeriums für Forschung und Technologie im Rahmen des Programmes Biologie und Technik     

Geometric design of motions constrained by a contacting surface pair

We discuss the following problem which arises in robot motion planning, NC machining and computer animation: Given are a fixed surface Ψ and N positions Φ_i of a moving surface Φ such that the Φ_i are in point contact with Ψ. Compute a smooth and fair Euclidean gliding motion Φ(t) of the surface Φ on the surface Ψ which interpolates (or approximates) the given positions Φ_i at time instances t_i. First we generalize interpolatory variational subdivision algorithms for curves to curves on surfaces. Second we study an unconstraint motion design algorithm which we then extend to the main contribution of this paper, an algorithm for the design of a motion constraint by a contacting surface pair. Both motion design algorithms use a feature point representation of the moving surface, subdivision algorithms for curves, instantaneous kinematics, and ideas from line geometry. Geometric methods are used for the numerical solution of the arising optimization problems.     

Physiological cost of energy-equivalent noise exposures with a rating level of 85 dB(A):: Hearing threshold shifts associated with energetically negligible continuous and impulse noise

In industry continuous or impulse noise does not occur exclusively; rather it is a combination of both. If low-level continuous noise or impulse noise (below 120 dB) is added to an already existing high-level continuous noise this often numerically causes no essential increase in the rating level. Yet, it cannot be expected that also aural strain of these exposures is always negligible. Therefore, in a cross-over test series, ten male subjects (Ss) were exposed to white noise of 94 dB(A) for 1 h (TS I), energy-equivalent to an 8 h-rating level L_Ard of 85 dB(A). In a second test series (TS II) the same exposure was combined with 900 energetically negligible 5-ms impulses with a noise level of 113 dB(A) which increased the rating level by only 0.4 dB. The noise exposure of TS I and TS II was followed by an idealized resting phase in a soundproof cabin. In a third test series (TS III) the continuous noise of 94 dB(A) / 1 h was followed by 3 h of white noise at 70 dB(A). Such an additional load increases the L_Ard by merely 0.1 dB to 85.1 dB(A). In all three test series, the noise-induced temporary threshold shift (TTS₂) and its restitution were measured. The continuous noise exposure of 94 dB(A) for 1 h was associated with a TTS₂ of around 20 dB which disappeared completely after about 2 h. The additional impulse noise caused a small increase in the TTS₂ and a prolongation of the restitution time. The maximum mean temporary threshold shift for the group increased only slightly (from 22.5 to 25.9 dB, which nevertheless can be statistically proven at a significance level of p 0.99). Yet, more importantly, the restitution time increased from 126 to 175 min, i. e. 3 h, which can be statistically proven at a significance level of p0.95. The TTS₂-values of TS III did not differ significantly from those resulting from TS I. That was expected as the conditions up to that point in time were identical. But due to the additional subsequent exposure, the mean restitution time increased considerably from 126 min up to 240 min (4 h). The mean total physiological cost represented by the integrated restitution temporary threshold shift (IRTTS) increased in TS II by approximately 40% and in TS III even by 140%.

Relevance to industry

The results of the study show that levels of noise which have no influence on the rating level which traditionally is calculated according to the energy-equivalence principle are often of great importance, as they can lead to considerably prolonged restitution times. Therefore, the purely energy-equivalent determination of the rating level of both impulse noise and low sound levels can lead to an underestimation of latent problems so that over time a reversible TTS can evolve into a permanent threshold shift. The results are also of importance for the acoustic design of break rooms for noise-exposed workers. There should be conditions that allow an undisturbed restitution of hearing.     

Personality and Emotion: Test of Gray's Personality Theory by Means of an fMRI Study.

Although it is known that there are fundamental personality differences in the behavioral responses to emotional stimuli, traits have scarcely been investigated in this context by means of functional imaging studies. To maximize the variance with respect to personality, the authors tested 12 control subjects and 12 subjects who had sadomasochistic experiences with respect to the relationship between J. A. Gray's (1970) personality dimensions, the behavioral approach system (BAS) and the behavioral inhibition system (BIS), and brain activity in regions of interest. The BIS was associated with activity in numerous brain areas in response to fear, disgust, and erotic visual stimuli, whereas few associations could he detected between the BAS and brain activity in response to disgust and erotic stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evolution of Globular Microstructure in New Rheocasting and Super Rheocasting Semi‐Solid Slurries

Based on the solidification theory for metal alloys, a simple recipe for the controlled processing of globular microstructures without external stirring is presented: Firstly, small solidification nuclei must be distributed homogeneously throughout a melt. In New Rheocasting (NRC) these nuclei are formed by forced homogeneous nucleation due to partial quenching of the melt, while in Super Rheocasting (SRC) the nuclei are “second phase particles” in specially designed alloys, which are grown in a controlled fashion in a certain temperature range. Potential alloy compositions for SRC are provided. Secondly, given these melts with small particles in them, globular growth can be assured by utilizing the Gibbs‐Thomson “self healing effect” and slow further cooling to allow diffusion in the melt and to suppress constitutional supercooling. This simple recipe is applicable to various ferrous and non‐ferrous alloys. If an SRC alloy is cooled more rapidly than necessary for globular growth of the primary phase, but is held sufficiently long in the SRC range for dispersoid formation, these dispersoids can act as potent grain refiners and possibly enhance elevated temperature properties. A combination of both processes by using SRC alloys in the NRC equipment may lead to pressure tight castings with low porosity and finer grain structure than can be achieved with NRC on its own, and consequently, better mechanical properties.     

Light Microscopy 1981: The State of the Art

Melamine-formaldehyde, a universally used technical aminoplast, can be modified into a water-compatible electron microscopic embedding medium. The complete processing of tissues—from fixation to sectioning—is described in this paper. It produces stable sections showing remarkable ultrastructural detail.     

Real-time contactless measurement of robot pose in six degrees of freedom

For dynamically measuring position in three degrees of freedom laser tracking systems are well known. Up to now no possibility to measure also orientation using the same laser beam has been known. We present a technique to incorporate orientation measurement into a laser tracking system that requires only minor changes in the existing hardware. The method is based on the analysis of an image of the reflected laser beam intensity distribution. In this image the edges of a slightly modified retroreflector represent a function of the orientation of the end-effector holding the retroreflector. It is shown that from this image the orientation can be determined uniquely and in real time.

A laser tracking system including position and orientation measurement constitutes an instrument to accurately determine robot performance as well as to acquire hints on how to improve robot models and control algorithms.