Ultra high pressure homogenization (UHPH) inactivation of Bacillus amyloliquefaciens spores in phosphate buffered saline (PBS) and milk

Ultra high pressure homogenization (UHPH) opens up new areas for dynamic high pressure assisted thermal sterilization of liquids. Bacillus amyloliquefaciens spores are resistant to high isostatic pressure and temperature and were suggested as potential surrogate for high pressure thermal sterilization validation. B. amyloliquefaciens spores suspended in PBS buffer (0.01 M, pH 7.0), low fat milk (1.5%, pH 6.7), and whole milk (3.5%, pH 6.7) at initial concentration of similar to 10(6) CFU/mL were subjected to UHPH treatments at 200, 300, and 350 MPa with an inlet temperature at similar to 80 degrees C. Thermal inactivation kinetics of B. amyloliquefaciens spores in PBS and milk were assessed with thin wall glass capillaries and modeled using first-order and Weibull models. The residence time during UHPH treatments was estimated to determine the contribution of temperature to spore inactivation by UHPH. No sublethal injury was detected after UHPH treatments using sodium chloride as selective component in the nutrient agar medium. The inactivation profiles of spores in PBS buffer and milk were compared and fat provided no clear protective effect for spores against treatments. Treatment at 200 MPa with valve temperatures lower than 125 degrees C caused no reduction of spores. A reduction of 3.5 log(10)CFU/mL of B. amyloliquefaciens spores was achieved by treatment at 350 MPa with a valve temperature higher than 150 degrees C. The modeled thermal inactivation and observed inactivation during UHPH treatments suggest that temperature could be the main lethal effect driving inactivation.

Reform der Erziehung. Eine Auseinandersetzung mit Andreas Flitner

Hans-Ulrich Grunder diskutiert am Beispiel von Andreas Flitners „Reform der Erziehung", ob eine pädagogische Aktualisierung ohne Rückgriff auf die Ergebnisse der bildungshistorischen Forschung möglich ist. Er versucht die These zu begründen, daß ohne Beachtung der Historiographie eine legitime Pädagogik nicht entwickelt werden kann. (DIPF/Orig.)

Decision tools for bacterial blight resistance gene deployment in rice-based agricultural ecosystems

Attempting to achieve long-lasting and stable resistance using uniformly deployed rice varieties is not a sustainable approach. The real situation appears to be much more complex and dynamic, one in which pathogens quickly adapt to resistant varieties. To prevent disease epidemics, deployment should be customized and this decision will require interdisciplinary actions. This perspective article aims to highlight the current progress on disease resistance deployment to control bacterial blight in rice. Although the model system rice-Xanthomonas oryzae pv. oryzae has distinctive features that underpin the need for a case-by-case analysis, strategies to integrate those elements into a unique decision tool could be easily extended to other crops.

Evaluation of reproductive barriers contributes to the development of novel interspecific hybrids in the Kalanchoe genus

Background: Interspecific hybridization is a useful tool in ornamental breeding to increase genetic variability and introduce new valuable traits into existing cultivars. The successful formation of interspecific hybrids is frequently limited by the presence of pre- and post-fertilization barriers. In the present study, we investigated the nature of hybridization barriers occurring in crosses between Kalanchoe species and evaluated possibilities of obtaining interspecific hybrids. Results: The qualitative and quantitative analyses of pollen tube growth in situ were performed following intra-and interspecific pollinations. They revealed occurrence of pre-fertilization barriers associated with inhibition of pollen germination on the stigma and abnormal growth of pollen tubes. Unilateral incongruity related to differences in pistil length was also observed. The pollen quality was identified as a strong factor influencing the number of pollen tubes germinating in the stigma. In relation to post-fertilization barriers, endosperm degeneration was a probable barrier hampering production of interspecific hybrids. Moreover, our results demonstrate the relation of genetic distance estimated by AFLP marker analysis of hybridization partners with cross-compatibility of Kalanchoe species. At the same time, differences in ploidy did not influence the success of interspecific crosses. Conclusions: Our study presents the first comprehensive analysis of hybridization barriers occurring within Kalanchoe genus. Reproductive barriers were detected on both, pre- and post-fertilization levels. This new knowledge will contribute to further understanding of reproductive isolation of Kalanchoe species and facilitate breeding of new cultivars. For the first time, interspecific hybrids between K. nyikae as maternal plant and K. blossfeldiana as well as K. blossfeldiana and K. marnieriana were generated.

Prawda

Immer wieder haben sich im Laufe der Geschichte Erzieher mit der Frage beschäftigt, wie der nachfolgenden Generation die einmal gewonnenen Einsichten und Wahrheiten abendländisch-gesellschaftlichen Lebens und Denkens zu vermitteln seien. Gelang ihnen eine Antwort, wurden sie zu Klassikern der Pädagogik. Auch Bertolt Brecht, der Lehrstückeschreiber, hat sich der Erziehungsproblematik angenommen und es droht ihm dasselbe Schicksal: Er, der einst als „Bürgerschreck“ galt, wird heute in die Schar der Klassiker eingereiht. Wie erklärt sich dieses Phänomen? Der vorliegende Text basiert auf der These, dass schon eine gründliche Analyse eines kleinen Abschnitts aus Brechts Werk eher über das Phänomen Aufschluss geben kann als die extensive Lektüre seiner „Gesammelten Schriften“.(DIPF/Orig.)

Genetic variation of temperature-regulated curd induction in cauliflower: elucidation of floral transition by genome-wide association mapping and gene expression analysis

Cauliflower (Brassica oleracea var. botrytis) is a vernalization-responsive crop. High ambient temperatures delay harvest time. The elucidation of the genetic regulation of floral transition is highly interesting for a precise harvest scheduling and to ensure stable market supply. This study aims at genetic dissection of temperature-dependent curd induction in cauliflower by genome-wide association studies and gene expression analysis. To assess temperature dependent curd induction, two greenhouse trials under distinct temperature regimes were conducted on a diversity panel consisting of 111 cauliflower commercial parent lines, genotyped with 14,385 SNPs. Broad phenotypic variation and high heritability (0.93) were observed for temperature-related curd induction within the cauliflower population. GWA mapping identified a total of 18 QTL localized on chromosomes O1, O2, O3, O4, O6, O8, and O9 for curding time under two distinct temperature regimes. Among those, several QTL are localized within regions of promising candidate flowering genes. Inferring population structure and genetic relatedness among the diversity set assigned three main genetic clusters. Linkage disequilibrium (LD) patterns estimated global LD extent of r(2) = 0.06 and a maximum physical distance of 400 kb for genetic linkage. Transcriptional profiling of flowering genes FLOWERING LOCUS C (BoFLC) and VERNALIZATION 2 (BoVRN2) was performed, showing increased expression levels of BoVRN2 in genotypes with faster curding. However, functional relevance of BoVRN2 and BoFLC2 could not consistently be supported, which probably suggests to act facultative and/or might evidence for BoVRN2/BoFLC-independent mechanisms in temperature regulated floral transition in cauliflower. Genetic insights in temperature-regulated curd induction can underpin genetically informed phenology models and benefit molecular breeding strategies toward the development of thermo-tolerant cultivars.

Interaction-free measurements by quantum Zeno stabilization of ultracold atoms

Quantum mechanics predicts that our physical reality is influenced by events that can potentially happen but factually do not occur. Interaction-free measurements (IFMs) exploit this counterintuitive influence to detect the presence of an object without requiring any interaction with it. Here we propose and realize an IFM concept based on an unstable many-particle system. In our experiments, we employ an ultracold gas in an unstable spin configuration, which can undergo a rapid decay. The object-realized by a laser beam-prevents this decay because of the indirect quantum Zeno effect and thus, its presence can be detected without interacting with a single atom. Contrary to existing proposals, our IFM does not require single-particle sources and is only weakly affected by losses and decoherence. We demonstrate confidence levels of 90%, well beyond previous optical experiments.

Schulzeitverkürzung und Studiendauer

Der vorliegende Wiederabdruck eines 1937 publizierten Textes rückt die Aktualität der damaligen bildungspolitischen Reformbemühungen zur Schulzeitverkürzung und Studiendauer in den Vordergrund. (DIPF/Bal)

Metabolite profiling of somatic embryos of Cyclamen persicum in comparison to zygotic embryos, endosperm, and testa

Somatic embryogenesis has been shown to be an efficient in vitro plant regeneration system for many crops such as the important ornamental plant Cyclamen persicum, for which this regeneration pathway of somatic embryogenesis is of interest for the vegetative propagation of parental lines as well as elite plants. However, somatic embryogenesis is not commercially used in many crops due to several unsolved problems, such as malformations, asynchronous development, deficiencies in maturation and germination of somatic embryos. In contrast, zygotic embryos in seeds develop and germinate without abnormalities in most cases. Instead of time-consuming and labor-intensive experiments involving tests of different in vitro culture conditions and plant growth regulator supplements, we follow a more directed approach. Zygotic embryos served as a reference and were compared to somatic embryos in metabolomic analyses allowing the future optimization of the in vitro system. The aims of this study were to detect differences in the metabolite profiles of torpedo stage somatic and zygotic embryos of C. persicum. Moreover, major metabolites in endosperm and testa were identified and quantified. Two sets of extracts of two to four biological replicates each were analyzed. In total 52 metabolites were identified and quantified in the different tissues. One of the most significant differences between somatic and zygotic embryos was that the proline concentration in the zygotic embryos was about 40 times higher than that found in somatic embryos. Epicatechin, a scavenger for reactive oxygen species, was found in highest abundance in the testa. Sucrose, the most abundant metabolite was detected in significantly higher concentrations in zygotic embryos. Also, a yet unknown trisaccharide, was significantly enriched in zygotic embryos.

Kultureller Wandel und Musikpädagogik

Kultureller Wandel und Musikpädagogik stehen in einem dialektischen Verhältnis zueinander, weil zu den Schwerpunktfeldern musikpädagogischer Theoriebildung und schulischer wie außerschulischer Praxis das sich wandelnde kulturelle Handeln von (jungen) Menschen gehört, zugleich aber die Musikpädagogik in ihrem Selbstverständnis selbst einem Wandel unterliegt. Unter dem Thema der 99er Tagung des AMPF >Kultureller Wandel und Musikpädagogik< sind daher zahlreiche Beiträge zusammengekommen, die in ihrer thematischen Breite zentrale Aspekte dieses kulturpolitischen wie auch musikpädagogischen Wandels aufnehmen und so einen Beitrag zur theoretischen Reflexion bzw. Begründung des Kulturbegriffs und seine Bedeutung für das Handlungsfeld der schulischen und außerschulischen Sozialisation leisten. (DIPF/Orig.)

Rapid hydrothermal cooling above the axial melt lens at fast-spreading mid-ocean ridge

Axial melt lenses sandwiched between the lower oceanic crust and the sheeted dike sequences at fast-spreading mid-ocean ridges are assumed to be the major magma source of oceanic crust accretion. According to the widely discussed "gabbro glacier'' model, the formation of the lower oceanic crust requires efficient cooling of the axial melt lens, leading to partial crystallization and crystal-melt mush subsiding down to lower crust. These processes are believed to be controlled by periodical magma replenishment and hydrothermal circulation above the melt lens. Here we quantify the cooling rate above melt lens using chemical zoning of plagioclase from hornfelsic recrystallized sheeted dikes drilled from the East Pacific at the Integrated Ocean Drilling Program Hole 1256D. Weestimate the cooling rate using a forward modelling approach based on CaAl-NaSi interdiffusion in plagioclase. The results show that cooling from the peak thermal overprint at 1000-10506 degrees C to 6006 degrees C are yielded within about 10-30 years as a result of hydrothermal circulation above melt lens during magma starvation. The estimated rapid hydrothermal cooling explains how the effective heat extraction from melt lens is achieved at fast-spreading mid-ocean ridges.

Cardiac T2-mapping using a fast gradient echo spin echo sequence - first in vitro and in vivo experience

Background: The aim of this study was the evaluation of a fast Gradient Spin Echo Technique (GraSE) for cardiac T2-mapping, combining a robust estimation of T2 relaxation times with short acquisition times. The sequence was compared against two previously introduced T2-mapping techniques in a phantom and in vivo. Methods: Phantom experiments were performed at 1.5 T using a commercially available cylindrical gel phantom. Three different T2-mapping techniques were compared: a Multi Echo Spin Echo (MESE; serving as a reference), a T2-prepared balanced Steady State Free Precession (T2prep) and a Gradient Spin Echo sequence. For the subsequent in vivo study, 12 healthy volunteers were examined on a clinical 1.5 T scanner. The three T2-mapping sequences were performed at three short-axis slices. Global myocardial T2 relaxation times were calculated and statistical analysis was performed. For assessment of pixel-by-pixel homogeneity, the number of segments showing an inhomogeneous T2 value distribution, as defined by a pixel SD exceeding 20 % of the corresponding observed T2 time, was counted. Results: Phantom experiments showed a greater difference of measured T2 values between T2prep and MESE than between GraSE and MESE, especially for species with low T1 values. Both, GraSE and T2prep resulted in an overestimation of T2 times compared to MESE. In vivo, significant differences between mean T2 times were observed. In general, T2prep resulted in lowest (52.4 +/- 2.8 ms) and GraSE in highest T2 estimates (59.3 +/- 4.0 ms). Analysis of pixel-by-pixel homogeneity revealed the least number of segments with inhomogeneous T2 distribution for GraSE-derived T2 maps. Conclusions: The GraSE sequence is a fast and robust sequence, combining advantages of both MESE and T2prep techniques, which promises to enable improved clinical applicability of T2-mapping in the future. Our study revealed significant differences of derived mean T2 values when applying different sequence designs. Therefore, a systematic comparison of different cardiac T2-mapping sequences and the establishment of dedicated reference values should be the goal of future studies.

Lehr- und Lernforschung in der Musikpädagogik

Das Thema der Tagung >Lehr- und Lernforschung in der Musikpädagogik< in Lingen im Herbst 2005 greift Forschungsbereiche auf, die für die Musikpädagogik vor dem Hintergrund der PISA-Studien im Allgemeinen und der gegenwärtig stattfindenden Entwicklung von Bildungsstandards für den Musikunterricht im Besonderen von zunehmender Bedeutung sind und angesichts der aktuellen Diskussion zur Einrichtung von Ganztagsschulen und deren absehbaren Konsequenzen für den herkömmlichen Musikunterricht der Notwendigkeit Rechnung tragen, die Fragestellungen der Unterrichtsforschung mehr als bisher auch auf Lehr- und Lernprozesse in den außerschulischen Bereichen zu erweitern mit dem Ziel einer Vernetzung der musikpädagogischen Forschung mit Ansätzen und Ergebnissen der Jugendsoziologie einerseits und andererseits der Erforschung des Musiklernens bei Erwachsenen und Senioren in der Lebensspanne. (DIPF/Orig.)

Interkulturalität als Gegenstand der Musikpädagogik

Zu Beginn des 21. Jahrhunderts ist die Globalisierung längst dem rein theoretischen Diskurs entwachsen und maßgeblich prägende Instanz des gesellschaftlichen Lebens geworden. Globalisierung, das impliziert alltäglich gewordene Begegnungen mit dem Fremden, Revision von Wertvorstellungen, Veränderung der Umgangsweisen mit Musik, und insbesondere bei Heranwachsenden impliziert Globalisierung erweiterte Formen zur Sozialisation durch eine (Musik-)Kultur der Vielfalt. Mit Vielfalt und Wandel gehen aber auch Verlustängste einher, sodass entsprechende Tendenzen gelegentlich sowohl zu Konflikten in der Begegnung als auch zu Abschottungstendenzen zwecks Erhalts des Vertrauten führen. Ein so tiefgreifender Wandel, der an territorialen Grenzen nicht mehr Halt macht und ontologische Grundüberzeugungen prinzipiell in Zweifel zieht, lässt es als notwendig erscheinen, zu begleiten und so Musikpädagogik auch "interkulturell" zu verstehen. Folglich gilt es, wissenschaftsorientierte Standortbestimmungen vorzunehmen, veränderte musikpädagogische Konzepte in einer Kulturlandschaft des "global village" zu bedenken und restaurative Bestrebungen in der Musikpädagogik kritisch zu beleuchten. Dieser Band enthält Vorträge der Jahrestagung des AMPF vom Oktober 2006 in Lingen zur Tagungsthematik "Interkulturalität als Gegenstand der Musikpädagogik". Darüber hinaus versammelt er auch auf der Tagung gehaltene freie Forschungsbeiträge. (DIPF/Orig.)