72 research outputs found

    Einstellung von Schülern zu Schule und Sachunterricht:Erfassung und Differenzierung von typologischen Einstellungsausprägungen bei Grundschülern

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    Zur Erfassung der Einstellung von Grundschulkindern zur Schule und zum Sachunterricht wurde ein Erhebungsinstrument im Sinne der klassischen Testtheorie und Testkonstruktion (z.B. Rost, 1996) entwickelt. Dieses Instrument ist ein systematisch konstruierter Fragebogen mit vier verschiedenen Subskalen („Schule und Lernen“, „Bedeutung von Lernen im Sachunterricht“, „Verhalten zu Mitschülern“, „didaktischmethodische Ausgestaltung des Sachunterrichts“), das letztlich mit insgesamt 29 Items (von zuvor 87 Items) die Einstellung der Schüler zu Schule und Sachunterricht operationalisiert. Mit diesem Instrument wurden insgesamt 344 Grundschüler der Jahrgangsstufen 1-4 befragt. Mit Hilfe spezifischer, statistischer Verfahren konnten drei „Einstellungstypen“ identifiziert und beschrieben werden: Der Lernfreude-Typ, der Gelangweilt-Frustrierte Typ und der Zielorientierte Leistungs-Typ. Die didaktisch-methodische Ausgestaltung des Sachunterrichtes im Schülerurteil hat einen bedeutenden Einfluss auf die Lernprozesse. Deshalb stehen mögliche didaktisch-methodische Konsequenzen für den Sach- bzw. Biologieunterricht im Focus des Interesses

    Toeplitz Quantization and Asymptotic Expansions: Geometric Construction

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    For a real symmetric domain GR/KR, with complexification GC/KC, we introduce the concept of ''star-restriction'' (a real analogue of the ''star-products'' for quantization of Kähler manifolds) and give a geometric construction of the GR-invariant differential operators yielding its asymptotic expansion

    Is there a Jordan geometry underlying quantum physics?

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    There have been several propositions for a geometric and essentially non-linear formulation of quantum mechanics. From a purely mathematical point of view, the point of view of Jordan algebra theory might give new strength to such approaches: there is a ``Jordan geometry'' belonging to the Jordan part of the algebra of observables, in the same way as Lie groups belong to the Lie part. Both the Lie geometry and the Jordan geometry are well-adapted to describe certain features of quantum theory. We concentrate here on the mathematical description of the Jordan geometry and raise some questions concerning possible relations with foundational issues of quantum theory.Comment: 30 page

    Naïve and informed views on the nature of scientific inquiry in large-scale assessments: Two sides of the same coin or different currencies

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    Many models in the field of epistemic cognition conceptualize students' views as being on a continuum between the poles of naïve and informed views. Against this background, the aim of the present study was to find out whether views on the nature of scientific inquiry (NOSI views) should be conceptualized and quantitatively assessed in a more multiplistic manner, considering naïve and informed views in their own, separate dimensions. Based on a competence model defining three inquiry methods, we developed a Likert-scaled questionnaire containing 10 scales, each assessing one NOSI view. We administered the questionnaire to a sample of 802 students in the lower and upper levels of secondary school. Based on structural equation modeling, the analyses confirmed a 10-dimensional model, distinguishing between each naïve and informed views as the only adequate representation of the data. Latent class analysis and interview data revealed four profiles of NOSI views in the data, which differed with regard to their agreement or disagreement with different naïve and informed views. We interpret these findings as evidence that supports more multiplistic models, with relevance to conceptualizing, measuring, and fostering NOSI views. We derive future directions of nature of science and NOSI research linking basic and applied research using experimental studies. © 2019 The Author. Journal of Research in Science Teaching published by Wiley Periodicals, Inc

    Nonparametric Information Geometry

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    The differential-geometric structure of the set of positive densities on a given measure space has raised the interest of many mathematicians after the discovery by C.R. Rao of the geometric meaning of the Fisher information. Most of the research is focused on parametric statistical models. In series of papers by author and coworkers a particular version of the nonparametric case has been discussed. It consists of a minimalistic structure modeled according the theory of exponential families: given a reference density other densities are represented by the centered log likelihood which is an element of an Orlicz space. This mappings give a system of charts of a Banach manifold. It has been observed that, while the construction is natural, the practical applicability is limited by the technical difficulty to deal with such a class of Banach spaces. It has been suggested recently to replace the exponential function with other functions with similar behavior but polynomial growth at infinity in order to obtain more tractable Banach spaces, e.g. Hilbert spaces. We give first a review of our theory with special emphasis on the specific issues of the infinite dimensional setting. In a second part we discuss two specific topics, differential equations and the metric connection. The position of this line of research with respect to other approaches is briefly discussed.Comment: Submitted for publication in the Proceedings od GSI2013 Aug 28-30 2013 Pari

    Carleson Measures and Toeplitz Operators

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    In this last chapter we shall describe an application of the Kobayashi distance to geometric function theory and functional analysis of holomorphic functions

    Fredholmness of Toeplitz operators on the Fock space

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    The Fredholm property of Toeplitz operators on the pp-Fock spaces FαpF_\alpha^p on Cn\mathbb{C}^n is studied. A general Fredholm criterion for arbitrary operators from the Toeplitz algebra Tp,α\mathcal{T}_{p,\alpha} on FαpF_\alpha^p in terms of the invertibility of limit operators is derived. This paper is based on previous work, which establishes corresponding results on the unit balls Bn\mathbb{B}^n

    Critical evaluation of key evidence on the human health hazards of exposure to bisphenol A

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    Despite the fact that more than 5000 safety-related studies have been published on bisphenol A (BPA), there seems to be no resolution of the apparently deadlocked controversy as to whether exposure of the general population to BPA causes adverse effects due to its estrogenicity. Therefore, the Advisory Committee of the German Society of Toxicology reviewed the background and cutting-edge topics of this BPA controversy. The current tolerable daily intake value (TDI) of 0.05 mg/kg body weight [bw]/day, derived by the European Food Safety Authority (EFSA), is mainly based on body weight changes in two- and three-generation studies in mice and rats. Recently, these studies and the derivation of the TDI have been criticized. After having carefully considered all arguments, the Committee had to conclude that the criticism was scientifically not justified; moreover, recently published additional data further support the reliability of the two-and three-generation studies demonstrating a lack of estrogen-dependent effects at and below doses on which the current TDI is based. A frequently discussed topic is whether doses below 5 mg/ kg bw/day may cause adverse health effects in laboratory animals. Meanwhile, it has become clear that positive results from some explorative studies have not been confirmed in subsequent studies with higher numbers of animals or a priori defined hypotheses. Particularly relevant are some recent studies with negative outcomes that addressed effects of BPA on the brain, behavior, and the prostate in rodents for extrapolation to the human situation. The Committee came to the conclusion that rodent data can well be used as a basis for human risk evaluation. Currently published conjectures that rats are insensitive to estrogens compared to humans can be refuted. Data from toxicokinetics studies show that the half-life of BPA in adult human subjects is less than 2 hours and BPA is completely recovered in urine as BPA-conjugates. Tissue deconjugation of BPA-glucuronide and -sulfate may occur. Because of the extremely low quantities, it is only of minor relevance for BPA toxicity. Biomonitoring studies have been used to estimate human BPA exposure and show that the daily intake of BPA is far below the TDI for the general population. Further topics addressed in this article include reasons why some studies on BPA are not reproducible; the relevance of oral versus non-oral exposure routes; the degree to which newborns are at higher systemic BPA exposure; increased BPA exposure by infusions in intensive care units; mechanisms of action other than estrogen receptor activation; and the current regulatory status in Europe, as well as in the USA, Canada, Japan, New Zealand, and Australia. Overall, the Committee concluded that the current TDI for BPA is adequately justified and that the available evidence indicates that BPA exposure represents no noteworthy risk to the health of the human population, including newborns and babies

    ANALYSIS ON SYMMETRIC CONES (Oxford Mathematical Monographs)

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