309 research outputs found
Environmental Factors Affect Acidobacterial Communities below the Subgroup Level in Grassland and Forest Soils
No full textIn soil, Acidobacteria constitute on average 20% of all bacteria, are highly diverse, and are physiologically active in situ. However, their individual functions and interactions with higher taxa in soil are still unknown. Here, potential effects of land use, soil properties, plant diversity, and soil nanofauna on acidobacterial community composition were studied by cultivation-independent methods in grassland and forest soils from three different regions in Germany. The analysis of 16S rRNA gene clone libraries representing all studied soils revealed that grassland soils were dominated by subgroup Gp6 and forest soils by subgroup Gp1 Acidobacteria. The analysis of a large number of sites (n = 57) by 16S rRNA gene fingerprinting methods (terminal restriction fragment length polymorphism [T-RFLP] and denaturing gradient gel electrophoresis [DGGE]) showed that Acidobacteria diversities differed between grassland and forest soils but also among the three different regions. Edaphic properties, such as pH, organic carbon, total nitrogen, C/N ratio, phosphorus, nitrate, ammonium, soil moisture, soil temperature, and soil respiration, had an impact on community composition as assessed by fingerprinting. However, interrelations with environmental parameters among subgroup terminal restriction fragments (T-RFs) differed significantly, e.g., different Gp1 T-RFs correlated positively or negatively with nitrogen content. Novel significant correlations of Acidobacteria subpopulations (i.e., individual populations within subgroups) with soil nanofauna and vascular plant diversity were revealed only by analysis of clone sequences. Thus, for detecting novel interrelations of environmental parameters with Acidobacteria, individual populations within subgroups have to be considered.Astrid Naether, Bärbel U. Foesel, Verena Naegele, Pia K. Wüst, Jan Weinert, Michael Bonkowski, Fabian Alt, Yvonne Oelmann, Andrea Polle, Gertrud Lohaus, Sonja Gockel, Andreas Hemp, Elisabeth K. V. Kalko, Karl Eduard Linsenmair, Simone Pfeiffer, Swen Renner, Ingo Schöning, Wolfgang W. Weisser, Konstans Wells, Markus Fischer, Jörg Overmann, and Michael W. Friedric
Determinants of Acidobacteria activity inferred from the relative abundances of 16S rRNA transcripts in German grassland and forest soils
No full text16S rRNA genes and transcripts of Acidobacteria were investigated in 57 grassland and forest soils of three different geographic regions. Acidobacteria contributed 9-31% of bacterial 16S rRNA genes whereas the relative abundances of the respective transcripts were 4-16%. The specific cellular 16S rRNA content (determined as molar ratio of rRNA:rRNA genes) ranged between 3 and 80, indicating a low in situ growth rate. Correlations with flagellate numbers, vascular plant diversity and soil respiration suggest that biotic interactions are important determinants of Acidobacteria 16S rRNA transcript abundances in soils. While the phylogenetic composition of Acidobacteria differed significantly between grassland and forest soils, high throughput denaturing gradient gel electrophoresis and terminal restriction fragment length polymorphism fingerprinting detected 16S rRNA transcripts of most phylotypes in situ. Partial least squares regression suggested that chemical soil conditions such as pH, total nitrogen, C:N ratio, ammonia concentrations and total phosphorus affect the composition of this active fraction of Acidobacteria. Transcript abundance for individual Acidobacteria phylotypes was found to correlate with particular physicochemical (pH, temperature, nitrogen or phosphorus) and, most notably, biological parameters (respiration rates, abundances of ciliates or amoebae, vascular plant diversity), providing culture-independent evidence for a distinct niche specialization of different Acidobacteria even from the same subdivision
Temperament and interaction quality in the frist years of life - The longitudinal interplay of early temperament and maternal interaction quality in the context of unequal psychosocial resources
No full textKumulative Dissertation, Otto-Friedrich-Universität Bamberg, 2018Die Bedeutung der frühen Kindheit für die weitere Entwicklung findet in der Forschung zunehmend Beachtung. In dieser Hinsicht gelten die mütterliche Interaktionsqualität und das Temperament des Kindes für sich genommen beide als wichtige Prädiktoren. Verstärkt werden könnte ihr Effekt durch ihre Wechselwirkung, über die seit Jahrzehnten diskutiert wird. Die Befundlage gestaltet sich uneindeutig, jedoch gibt es Hinweise, dass die psychosozialen Ressourcen der Mutter eine Rolle dafür spielen könnten, wie sie insbesondere mit einem schwierigen Temperament ihres Kindes umgeht. Des Weiteren wurde bisher versäumt, das längsschnittliche Zusammenspiel der Variablen zu untersuchen, obwohl der Forschungsstand eine transaktionale wechselseitige Beeinflussung vermuten lässt.
Zur Untersuchung dieser Thesen wurden zwei Studien durchgeführt, die um eine dritte Studie ergänzt wurden, die der Untersuchung grundlegender Fragen rund um die Erfassung und das Verständnis frühkindlichen Temperaments diente. Die vorgelegte Synopse fasst die relevanten Theorien und Befunde zusammen, zeigt aktuelle Forschungsdesiderata auf, stellt Design und Ergebnisse der drei Studien vor und diskutiert schließlich deren Implikationen für tangierte Forschungs- und Praxisfelder. Die Studien greifen im Wesentlichen auf Daten des Nationalen Bildungspanels zurück, das an einer für das untersuchte Alter außergewöhnlich großen Stichprobe Befragungs- und Beobachtungsdaten erhoben hat, die eine Analyse der untersuchten Fragestellung ermöglichen.
Studie 1 stützt die Validität der verwendeten Einschätzungen der Mutter zum Temperament ihres Kindes und liefert Ansatzpunkte für eine Neubewertung des Forschungsstandes zu dieser Frage. Studie 2 und 3 zeigen, dass eine geringere Interaktionsqualität auf komplexe Weise mit einem schwierigeren Temperament assoziiert ist. Für Mütter, deren psychosoziale Ressourcen nicht eingeschränkt sind, fällt die Höhe dieses negativen Zusammenhangs im ersten Lebensjahr minimal aus, nimmt jedoch bis zum dritten Lebensjahr
kontinuierlich zu. Lagen hingegen mehrere Risikofaktoren vor, für die von einer belastenden Wirkung auf die psychosozialen Ressourcen der Mutter ausgegangen wird, war nicht nur eine deutlich geringere Interaktionsqualität, sondern auch ein wesentlich stärkerer Effekt des Temperaments zu beobachten. Im ersten Lebensjahr zeigten belastete Mütter eine besonders niedrige Interaktionsqualität, wenn ihr Kind ein schwieriges
Temperament aufwies, wohingegen ein einfaches Temperament die negative Wirkung der Belastungsfaktoren auf die Interaktionsqualität sogar zu einem großen Teil kompensieren konnte. Im zweiten und zu Beginn des dritten Lebensjahres zeigte sich kein solcher Interaktionseffekt und auch kein Zusammenhang eines schwierigen Temperaments mit der Interaktionsqualität belasteter Mütter.
Somit konnten die Studien die besondere Rolle des frühkindlichen Temperaments bestätigen, da sie zeigen, dass der negative Effekt eines schwierigen Temperaments im ersten Lebensjahr nicht nur konditional an das Vorliegen kumulierter Belastungen geknüpft ist, sondern umgekehrt auch deren negative Wirkung auf die Interaktionsqualität konditional davon abhängt, ob die Mutter vom Temperament ihres Kindes herausgefordert
ist. Dass ab dem zweiten Lebensjahr kein querschnittlicher Zusammenhang mehr zu beobachten ist, zeigt in Verbindung mit der hohen festgestellten Prädiktivität der Interaktionsqualität im ersten Lebensjahr, wie wichtig es ist, betroffene Mutter-Kind-Dyaden bereits im ersten Lebensjahr zu identifizieren und zu unterstützen, um weiteren ungünstigen Entwicklungen vorzubeugen. Daher sollten sowohl die Forschung zu frühen Interaktionen als auch die Kinder- und Jugendhilfe dem Temperament im ersten Lebensjahr künftig mehr Beachtung schenken
Application and Use of Multivariate Control Charts In a BTA Deep Hole Drilling Process
No full textDeep hole drilling methods are used for producing holes with a high length-to-diameter ratio, good surface finish and straightness. The process is subject to dynamic disturbances usually classified as either chatter vibration or spiralling. In this paper, we will focus on the application and use of multivariate control charts to monitor the process in order to detect chatter vibrations. The results showed that chatter is detected and some alarm signals occurs at time points which can be connected to physical changes of the process. --
Army's training revolution, 1973-1990: an overview.
No full textThis study of the Army’s training revolution from the mid-1970s through the decade of the 1980s is based primarily on training chapters prepared by the author and by Mr. Richard P. Weinert for the TRADOC Annual Historical Reviews. Table of contents include: the DePuy-Gorman initiatives; Starry changes to training; major training issues of the Otis and Richardson years; training in Vuono's architecture for the future Army; training and Thurman's vision of the Army; and Foss and new training challenges
Theory-oriented evaluation for the design of and research in gaming and simulation
No full textJan Klabbers introduced the terms science of analysis and science of design to indicate differences between the communities of theoretical research with gaming simulation and the game design practitioners. The science of analysis uses games and simulations as research methods to test theories in various fields. Accordingly, the external validity of findings is the most important criterion of success. Research in the science of design perspective emphasizes the design of the artifact, and testing its usability.“Usability” refers to the idea of designing artifacts for clearly-specified contexts of use for clearly-identified audiences. However, the way both communities are interconnected and in which ways they can be of mutual benefit remains puzzling and controversial. It is our aim to discuss the potential contributions of theory-based evaluation in order to link both communities. Theory-oriented evaluation approaches are based on logic models which have the function of outlining how the simulation, its participants, and its environment interact with each other, and elicit the simulation’s desired outcomes. In evaluation studies, logic models are primarily used to support the planning of the evaluation design, and to provide a framework for interpreting evaluation findings. Thus, theory-oriented evaluations go beyond mere outcome-evaluations not only because they take the effects of a simulation session into consideration, but also because they aspire to identify the crucial factors which cause or moderate such effects. For this purpose, theory-oriented evaluation is assigned to the design science tradition. Its primary aim is to gain evaluative knowledge from a particular gaming simulation which can then be used to improve the simulation and its implementation for practical purposes. We will illustrate our viewpoints by discussing the theory-oriented evaluation of SIMGAME, a simulation game for business education in secondary schools
Scientometric portrait of Nobel laureate Leland H. Hartwell
No full textLeland H. Hartwell was honoured with the Nobel Prize in Physiology or Medicine (2001) at his 62 years age and at 41 years of research publishing career. The first contribution of the author was in 1961 at the age of 22. The number of his contributions in a year peaked in 1997 when it touched 8. He had 108 publications during 1961 – 2001 in domains: Molecular Biology of Cell Cycle Regulation (43), Genetics of Cell Division (48), Genomic Re-arrangement and DNA Repair (9), Molecular Genetics of Yeast Cell Fission (5), and Drug Target Interaction (3) which were analysed for authorship pattern with his 101 collaborators. Most active researchers having number of publications with Leland H. Hartwell were : Weinert, T. A. (10), Garvik, B. M. (8), McLaughlin, C. S. (8), Jenness, D. D. (5). His productivity coefficient was 0.76 which clearly indicates that his productivity increased after 50 percentile age. Highest collaboration coefficient (1) for Leland H. Hartwell was found during 1963-1965, 1968-1969, 1977, 1981-1983, 1985-1990, 1996 and 1998-2001. Journals have been the most preferred channel of communication where, as many as 96 papers out of 108 have been published. The core journals publishing his papers were: Cell (14), Genetics (12), Mol. Cell Biol. (8), J. Bactariol. (7), J. Cell Biol. ( 7), Science (7) J. Mol. Biol.(6), Exp. Cell Res. (5), and Proc. Nat. Acad. Sci.(5). Publication density is 2.63 and Publication concentration is 14.63. Most prolific keywords in titles of publications were: Saccharomyces cerevisiae , Yeast , Cell division cycle , RAD9, DNA Damage , Genes , Cell cycle, Genetic control , Check point (s) , Cell division , Mutant of Yeast
Selecting Appropriate Phonological Awareness Indicators for the Kindergarten Cohort of the National Educational Panel Study:A Theoretical and Empirical Approach
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