A Noninformative Prior for Neural Networks

While many implementations of Bayesian neural networks use large, complex hierarchical priors, in much of modern Bayesian statistics, noninformative (flat) priors are very common. This paper introduces a noninformative prior for feed-forward neural networks, describing several theoretical and practical advantages of this approach. In particular, a simpler prior allows for a simpler Markov chain Monte Carlo algorithm. Details of MCMC implementation are included.     

Explaining Paradoxical Relations Between Academic Self-Concepts and Achievements: Cross-Cultural Generalizability of the Internal/External Frame of Reference Predictions Across 26 Countries.

The internal/external frame of reference (I/E) model explains a seemingly paradoxical pattern of relations between math and verbal self-concepts and corresponding measures of achievement, extends social comparison theory, and has important educational implications. In a cross-cultural study of nationally representative samples of 15-year-olds from 26 countries (total N = 55,577), I/E predictions were supported in that (a) math and verbal achievements were highly correlated, but math and verbal self-concepts were nearly uncorrelated; (b) math achievement had positive effects on math self-concept, but negative effects on verbal self-concept; and (c) verbal achievement had positive effects on verbal self-concept, but negative effects on math self-concept. Supporting the cross-cultural generalizability of predictions, multigroup structural equation models demonstrated good support for the generalizabilify of results across 26 countries participating in the Programme for International Student Assessment project sponsored by the Organisation for Economic Co-operation and Development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Demands on Attention and the Role of Response Priming in Visual Discrimination of Feature Conjunctions.

This study examined how response mapping of features within single- and multiple-feature targets affects decision-based processing and attentional capacity demands. Observers judged the presence or absence of 1 or 2 target features within an object either presented alone or with distractors. Judging the presence of 2 features relative to the less discriminable of these features alone was faster (conjunction benefits) when the task-relevant features differed in discriminability and were consistently mapped to responses. Conjunction benefits were attributed to asynchronous decision priming across attended, task-relevant dimensions. A failure to find conjunction benefits for disjunctive conjunctions was attributed to increased memory demands and variable feature-response mapping for 2- versus single-feature targets. Further, attentional demands were similar between single- and 2-feature targets when response mapping, memory demands, and discriminability of the task-relevant features were equated between targets. Implications of the findings for recent attention models are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Freeze substitution of high-pressure frozen samples: the visibility of biological membranes is improved when the substitution medium contains water

Biological membranes are often poorly visible with the electron microscope after high‐pressure freezing and freeze‐substitution. The water content of the sample and of the substitution medium is one factor among others that strongly influences membrane visibility. In order to investigate this effect, high‐pressure frozen yeast cells, rat‐pancreas tissue and arthropod tissue were freeze‐substituted with and without adding water to the substitution medium. The visibility of the biological membranes was generally improved if the substitution medium contained 1–5% water. The effect was especially pronounced in yeast cells, where membrane visibility was poor after freeze‐substitution with water‐free medium but good after addition of 5% water to the substitution medium.     

Die Relevanz einer institutionalisierten Ethik für eine professionelle Zahnmedizin

Definition of the problem

The concept of “ethics” has recently been incorporated into both the 2014 Model Professional Code for Dentists and the current version of the “National Competence-Based Catalog of Learning Objectives in Dental Medicine” (NKLZ, Nationaler Kompetenzbasierter Lernzielkatalog Zahnmedizin). The study presented here addresses the question which relevance this has for the relevance of the new concept accomplished for the dental profession and society.

Arguments

To this end, the societal processes that are related to the autonomous freedom of action of the dental profession are discussed. Therefore the sociological fields of discourse such as profession (and the effect of its constitutive antinomies), trust, education, expertise, practice of treatments and sanction are reviewed for their potential of having connections to each other and serving as a structural frame concerning an ethically reflected acting of the professional. The basis of the professional freedom of action is the trust of society and the individual patient in the professionally acting dentist.

Conclusion

The study arrives at the conclusion that it was a serious omission for many decades not to make young dentists aware of the ethical foundations of dental activity on an institutionally established basis and thus failing to encourage them to constantly reflect their professional expertise in relation to the problems to be solved. This deficit has now been identified. It is absolutely essential to implement an institutionalized structure dealing with ethical questions within the scope of dental medicine.

     

Thermochemical Investigations in the System Cadmium-Praseodymium Relevant for Pyrometallurgical Fuel Reprocessing

Vapor pressure measurements, in terms of a (non-)isothermal isopiestic method, were carried out in the system Cd-Pr between 749 K and 1067 K (476 °C and 794 °C). Thermodynamic activities of cadmium as a function of temperature were obtained directly for the composition ranging from 50.0 to 85.7 at. pct Cd. From these results, partial molar enthalpies of mixing of Cd were derived for the corresponding composition range. The activity values of Cd were converted to an average sample temperature of 823 K (550 °C) by applying an integrated form of the Gibbs–Helmholtz equation. These data indicate that Cd₂Pr and Cd₅₈Pr₁₃ are probably the most stable intermetallic compounds in this system. Using an activity value of Pr from the literature as integration constant, Gibbs–Duhem integration was performed, and integral Gibbs energies are presented at 823 K (550 °C), referred to Cd(l) and α-Pr(s). Gibbs energies of formation at the stoichiometric compositions of the phases Cd₆Pr, Cd₅₈Pr₁₃, Cd₄₅Pr₁₁, Cd₃Pr, and Cd₂Pr were determined to be about ?18.8, ?23.5, ?24.8, ?28.7, and ?33.8 kJ g-atom^?1 at 823 K (550 °C), respectively.