Background: Only data of published study results are available to the scientific community for further use such as informing future research and synthesis of available evidence. If study results are reported selectively, reporting bias and distortion of summarised estimates of effect or harm of treatments can occur. The publication and citation of results of clinical research conducted in Germany was studied.Methods: The protocols of clinical research projects submitted to the research ethics committee of the University of Freiburg in 2000 were (...) analysed. Published full articles in several databases were searched and investigators contacted. Data on study and publication characteristics were extracted from protocols and corresponding publications.Results: 299 study protocols were included. The most frequent study design was randomised controlled trial , followed by uncontrolled studies , laboratory studies and non-randomised studies . 182 were multicentre studies including 97 international collaborations. 152 of 299 had commercial funding and 46 non-commercial funding. 109 of the 225 completed protocols corresponded to at least one full publication ; the publication rate was 48%. 168 of 210 identified publications were cited in articles indexed in the ISI Web of Science. The median was 11 citations per publication .Conclusions: Results of German clinical research projects conducted are largely underreported. Barriers to successful publication need to be identified and appropriate measures taken. Close monitoring of projects until publication and adequate support provided to investigators may help remedy the prevailing underreporting of research. (shrink)

gl. 1. Geopoliticheskai︠a︡ determinat︠s︡ii︠a︡ kulʹtury i ėkonomiki. Rolʹ geograficheskikh faktorov v razvitii obshchestva ; Geopoliticheskie osobennosti sot︠s︡iokulʹturnoĭ istorii Rossii -- gl. 2. Kulʹturnai︠a︡ sostavli︠a︡i︠u︡shchai︠a︡ geopolitiki. Kulʹtura kak instrument geopolitiki ; Dialog kulʹtur v sovremennom mire: opasnai︠a︡ illi︠u︡zii︠a︡, otchai︠a︡nnai︠a︡ vera ili velenie vremeni?

Brain tumor classification plays a niche role in medical prognosis and effective treatment process. We have proposed a combined feature and image-based classifier for brain tumor image classification in this study. Carious deep neural network and deep convolutional neural networks -based architectures are proposed for image classification, namely, actual image feature-based classifier, segmented image feature-based classifier, actual and segmented image feature-based classifier, actual image-based classifier, segmented image-based classifier, actual and segmented image-based classifier, and finally, CFIC. The Kaggle Brain Tumor Detection (...) 2020 dataset has been used to train and test the proposed classifiers. Among the various classifiers proposed, the CFIC performs better than all other proposed methods. The proposed CFIC method gives significantly better results in terms of sensitivity, specificity, and accuracy with 98.86, 97.14, and 98.97%, respectively, compared with the existing classification methods. (shrink)

This paper presents the results of optical interferometry experiments in which the phase of photons in one arm of a Mach-Zehnder interferometer is modified by applying a transverse constriction. An equivalent quantum interferometry experiment using neutron de Broglie waves is discussed in which the observed phase shift is in the spirit of the force-free phase shift of the Aharonov-Bohm effects. In the optical experiments the experimental results are in excellent agreement with predictions.

The phenomenon of probability backflow, previously quantified for a free nonrelativistic particle, is considered for a free particle obeying Dirac's equation. It is shown that probability backflow can occur in the opposite direction to the momentum; that is to say, there exist positive-energy states in which the particle certainly has a positive momentum in a given direction, but for which the component of the probability flux vector in that direction is negative. It is shown that the maximum possible amount of (...) probability that can flow “backwards,” over a given time interval of duration T, depends on the dimensionless parameter ε = (4ℏ/mc2T)1/2, where m is the mass of the particle and c is the speed of light. At ε = 0, the nonrelativistic value of approximately 0.039 for this maximum is recovered. Numerical studies suggest that the maximum decreases monotonically as ε increases from 0, and show that it depends on the size of m, ℏ, and T, unlike the nonrelativistic case. (shrink)

At the end of the last century Paul Tannery published an article on geometry in eleventh-century Europe, which he began with the following statement:“This is not a chapter in the history of science; it is a study of ignorance, in a period immediately before the introduction into the West of Arab mathematics.”.

On Roger Bacon's life and works, by A. G. Little.--Der einfluss des Robert Grosseteste auf die wissenschaftliche richtung des Roger Bacon, von Ludwig Baur.--La place de Roger Bacon parmi les philosophes du XIIIe siècle, par François Picavet.--Roger Bacon and the Latin vulgate, by Francis Aidan, cardinal Gasquet.--Roger Bacon and philology, by S. A. Hirsch.--The place of Roger Bacon in the history of mathematics, by David Eugene Smith.--Roger Bacon und seine verdienste um die optik, von Eilhard Wiedemann.--Roger Bacons lehre von der (...) sinnlichen spezies und vom seḣvorgange, von Sebastian Vogl.--Roger Bacons art des wissenschaftlichen arbeitens dargestellt nach seiner schrift De speculis, von J. Würschmidt.--Roger Bacon et l'horreur du vide, par Pierre Duhem.--Roger Bacon, his relations to alchemy and chemistry, by M. M. Pattison Muir.--Roger Bacon and gunpowder, by H. W. L. Hime.--Roger Bacon and medicine, by E. Withington. (shrink)

This paper describes the topological aspect of a logic-based, artificial intelligence approach to formalising the qualitative description of spatial properties and relations, and reasoning about those properties and relations. This approach, known as RCC theory, has been under development for several years at the University of Leeds. The main rationale for this project is that qualitative descriptions of spatial properties and relationships, and qualitative spatial reasoning, are of fundamental importance in human thinking about the world: even where quantitative spatial data (...) are most important, they must be attached to the components of a perceived spatial structure if we are to make use of them. RCC theory covers other qualitative aspects of spatial description and reasoning, but the topological properties and relations of spatially extended entities are fundamental to our work. The topological formalisms used by mathematicians are, in general, not well suited to the task of formalising the kinds of ‘common-sense’ or ‘everyday’ qualitative spatial description and reasoning which are our primary interest. Nevertheless, we must come to grips with the concepts of topology as practised by mathematicians if we are not to risk constantly ‘reinventing wheels’. (shrink)

Fenomen russkogo kosmizma -- Nikolaĭ Fedorovich Fedorov -- Konstantin Ėduardovich T︠S︡iolkovskiĭ -- Vladimir Ivanovich Vernadskiĭ -- Aleksandr Leonidovich Chizhevskiĭ.