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- Hyalophora cecropia (1)
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- o-quinone isomerase (1)
- quinone (1)
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Orthopyroxenes of a high temperature protomylonite of the Ivrea Zone, Northern Italy show twin like polysynthetic lamellae parallel to {210} of the hypersthene host. The transformation is caused by plastic deformation under high metamorphic conditions which has resulted in dynamic recrystallization of pyroxene and plagioclase. The lamellae consist of clinohypersthene. The twin plane and the lamellar clino-orthoinversion of hypersthene due to natural deformation have not been described hitherto.
Several types of insect cuticle contain enzymes catalyzing the formation ofof adducts between N-acetyldopamine (NADA) and N-acetylhistidine (NAH). Two such adducts, NAH-NADA-I and NAH NADA-II, have been isolated and their structures determined. In one of the adducts the link connecting the two residues occurs between the I-position (ß-position) in the NADA side chain and the 1-N atom (τ-N) in the imidazole ring of histidine. Diphenoloxidase activity alone is not sufficient for formation of this adduct, whereas extracts containing both diphenoloxidase and o-quinone-p-quinone methide isomerase activities catalyze the coupling reaction. The adduct consists of a mixture of two diastereomers and they are presumably formed by spontaneous reaction between enzymatically produced NADA-p-quinone methide and N-acetylhistidine. The other adduct has been identified as a ring addition product of N-acetylhistidine and NADA. In contrast to the former adduct it can be formed by incubation of the two substrates with mushroom tyrosinase alone. An adduct between N-acetylhistidine and the benzodioxan-type NADA-dimer is produced in vitro, when the N-acetylhistidine-NADA adduct is incubated with NADA and locust cuticle containing a 1,2-dehydro-NADA generating enzyme system. Trimeric NADA-polymerization products of the substituted benzodioxan-type have been obtained from in vivo sclerotized locust cuticle, confirming the ability of cuticle to produce NADA-oligomers. The results indicate that some insect cuticles contain enzymes promoting linkage of oxidized NADA to histidine residues. It is suggested that histidine residues in the cuticular proteins can serve as acceptors for oxidized NADA and that further addition of NADA-residues to the phenolic groups of bound NADA can occur, resulting in formation of protein-linked NADA-oligomers. The coupling reactions identified may be an important step in natural cuticular sclerotization.
Earlier testing-the-limits research on age differences in cognitive plasticity of a memory skill was extended by 18 additional assessment and training sessions to explore whether older adults were able to catch up with additional practice and improved training conditions. The focus was on the method of loci, which requires mental imagination to encode and retrieve lists of words from memory in serial order. Of the original 37 subjects, 35 (16 young, ranging from 20 to 30 years of age, and 19 older adults, ranging from 66 to 80 years of age) participated in the follow-up study. Older adults showed sizable performance deficits when compared with young adults and tested for limits of reserve capacity. The negative age difference was substantial, resistant to extensive practice, and applied to all subjects studied. The primary origin for this negative age difference may be a loss in the production and use of mental imagination for operations of the mind.
Content: Introduction: Do the Arts Really Matter? Aesthetic Cognition and Human Development The Significance of Arts in Everyday Life: Evidence from Case StudiesArts and Quality of Experience: A Systematic Analysis The Conditions of Optimal Experience The Representation of Experience in Personality Consequences for Teaching the Arts
Inhalt: I. VERSCHLEPPUNGSMASSNAHMEN a.) Longa Oratio b.) Aktive und passive Art der Verschleppung II FORMALE VERHINDERUNGSTECHNIKEN a.) Intercession b.) Das Aufdecken und Herbeiführen von Formfehlern III. SAKRALE OBSTRUKTIONSMÖGLICHKEITEN a.) Manipulationen im Kalender b.) Servatio und Obnuntiatio c.) Mißachtung, Verbot und gesetzliche Restriktionen IV. VERWEIGERUNGSHALTUNG a.) Verweigerung der Beschlußfassung durch den Gesamtsenat b.) Boykott des Senats durch Senatoren c.) Magistratische Verweigerung V. KASSATION SCHLUSSBETRACHTUNG
The topography of first-order catchments in a region of western Amazonia was found to exhibit distinctive, recurrent features: a steep, straight lower side slope, a flat or nearly flat terrace at an intermediate elevation between valley floor and interfluve, and an upper side slope connecting interfluve and intermediate terrace. A detailed survey of soil-saturated hydraulic conductivity (K sat)-depth relationships, involving 740 undisturbed soil cores, was conducted in a 0.75-ha first-order catchment. The sampling approach was stratified with respect to the above slope units. Exploratory data analysis suggested fourth-root transformation of batches from the 0–0.1 m depth interval, log transformation of batches from the subsequent 0.1 m depth increments, and the use of robust estimators of location and scale. The K sat of the steep lower side slope decreased from 46 to 0.1 mm/h over the overall sampling depth of 0.4 m. The corresponding decrease was from 46 to 0.1 mm/h on the intermediate terrace, from 335 to 0.01 mm/h on the upper side slope, and from 550 to 0.015 mm/h on the interfluve. A depthwise comparison of these slope units led to the formulation of several hypotheses concerning the link between K sat and topography.
Prenant comme arrière-plan la discussion française sur l'immigration, l'article étudie le débat correspondant dans la sociologie allemande. Nous nous concentrons sur le devenir scolaire et les perspectives professionnelles des jeunes immigrés dont nous examinons les conditions politiques, économiques et familiales. Les principaux résultats de la recherche empirique de la décennie 1980-1990 sont présentés et la discussion théorique est restituée dans ses grandes lignes.
Cet article compare quelques points de départ de l'éducation civique en France, système laïque, et en R.F.A., système où les organisations religieuses sont établies au sein de l'État. Une analyse de développements récents suggère que les différences entre les deux systèmes se réduisent. En Allemagne comme en France, l'éducation civique s'organise de plus en plus autour d'une conception individualiste de citoyenneté. Nous faisons l'hypothèse que ce rapprochement est un effet concomitant de la massification de l'enseignement secondaire, commune aux deux pays.
Die französische Bildungssoziologie interessiert sich vor allem für die Reproduktion sozialer Schichtung; weil dazu zahlreiche und detaillierte Untersuchungen vorliegen, kann die Erforschung von Geschlechtsunterschieden das relative Gewicht von Schicht und Geschlecht bei der Entstehung von Schulnoten, Schullaufbahnen, Schulabschlüssen und Berufsentscheidungen gut vergleichen. In der Herstellung solcher Querverbindungen zwischen zwei Dimensionen sozialer Ungleichheit, die häufig getrennt untersucht werden, liegt eine der Stärken eines neuen französischen Buches über „Mädchen und Schule", das die folgende Übersicht in den Mittelpunkt stellt.