100 results match your criteria: "Radboud University of Nijmegen[Affiliation]"

How to make a living from anaerobic ammonium oxidation.

FEMS Microbiol Rev

May 2013

Department of Microbiology, Faculty of Science, Institute of Wetland and Water Research, Radboud University of Nijmegen, Nijmegen, The Netherlands.

Anaerobic ammonium-oxidizing (anammox) bacteria primarily grow by the oxidation of ammonium coupled to nitrite reduction, using CO2 as the sole carbon source. Although they were neglected for a long time, anammox bacteria are encountered in an enormous species (micro)diversity in virtually any anoxic environment that contains fixed nitrogen. It has even been estimated that about 50% of all nitrogen gas released into the atmosphere is made by these 'impossible' bacteria.

View Article and Find Full Text PDF

Resonant scatterers such as hydrogen adatoms can strongly enhance the low-energy density of states in graphene. Here, we study the impact of these impurities on electronic screening. We find a two-faced behavior: Kubo formula calculations reveal an increased dielectric function ε upon creation of midgap states but no metallic divergence of the static ε at small momentum transfer q→0.

View Article and Find Full Text PDF

Dialogical Self Theory is a recent development in the social sciences, based on a conception of the self as a society of mind. In this conception, the self is considered as extended to significant others in the environment, who populate the self as a dynamic multiplicity of I-positions between which dialogical or monological relationships may emerge. While from a spatial perspective the self is engaged in a process of positioning and counterpositioning in a globalizing society, from a temporal point of view the self is part of a process of positioning and repositioning in collective history and personal development.

View Article and Find Full Text PDF

In the Life Sciences 'omics' data is increasingly generated by different high-throughput technologies. Often only the integration of these data allows uncovering biological insights that can be experimentally validated or mechanistically modelled, i.e.

View Article and Find Full Text PDF

Anammox--growth physiology, cell biology, and metabolism.

Adv Microb Physiol

September 2012

Department of Microbiology, Institute of Wetland and Water Research (IWWR), Faculty of Science, Radboud University of Nijmegen, Nijmegen, The Netherlands.

Anaerobic ammonium-oxidizing (anammox) bacteria are the last major addition to the nitrogen-cycle (N-cycle). Because of the presumed inert nature of ammonium under anoxic conditions, the organisms were deemed to be nonexistent until about 15 years ago. They, however, appear to be present in virtually any anoxic place where fixed nitrogen (ammonium, nitrate, nitrite) is found.

View Article and Find Full Text PDF

The role of the frontal eye fields in oculomotor competition: image-guided TMS enhances contralateral target selection.

Cereb Cortex

April 2013

Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University of Nijmegen, 6525 EN Nijmegen, the Netherlands.

In order to execute a correct eye movement to a target in a search display, a saccade program toward the target element must be activated, while saccade programs toward distracting elements must be inhibited. The aim of the present study was to elucidate the role of the frontal eye fields (FEFs) in oculomotor competition. Functional magnetic resonance imaging-guided single-pulse transcranial magnetic stimulation (TMS) was administered over either the left FEF, the right FEF, or the vertex (control site) at 3 time intervals after target presentation, while subjects performed an oculomotor capture task.

View Article and Find Full Text PDF

The role of extra-framework and framework aluminium in wet-ion exchanged Fe-ZSM5 has been studied using (29)Si NMR and (27)Al triple quantum magic angle spinning (3QMAS) NMR. A series of samples were studied, the parent material, the wet ion exchanged Fe-ZSM5 and Fe-ZSM5 that has been used in the decomposition of N(2)O with varying reaction conditions. Various framework and extra-framework aluminium species have been identified.

View Article and Find Full Text PDF

Melting of graphene: from two to one dimension.

J Phys Condens Matter

May 2011

Radboud University of Nijmegen, Institute for Molecules and Materials, Nijmegen, The Netherlands.

The high temperature behaviour of graphene is studied by atomistic simulations based on an accurate interatomic potential for carbon. We find that clustering of Stone-Wales defects and formation of octagons are the first steps in the process of melting which proceeds via the formation of carbon chains. The molten state forms a three-dimensional network of entangled chains rather than a simple liquid.

View Article and Find Full Text PDF

Gall's visit to The Netherlands.

J Hist Neurosci

April 2011

Radboud University of Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands.

In March 1805, Franz Joseph Gall left Vienna to start what has become known as his cranioscopic tour. He traveled through Germany, Denmark, and The Netherlands. In this article, we will describe his visit to The Netherlands in greater detail, as it has not yet received due attention.

View Article and Find Full Text PDF

Theory of optically forbidden d-d transitions in strongly correlated crystals.

J Phys Condens Matter

September 2010

Radboud University of Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.

A general multiband formulation of the linear and nonlinear optical response functions for realistic models of correlated crystals is presented. Dipole-forbidden d-d optical transitions originate from vertex functions, which we consider assuming the locality of an irreducible four-leg vertex. The unified formulation for second- and third-order response functions in terms of the three-leg vertex is suitable for practical calculations in solids.

View Article and Find Full Text PDF

In the earliest stages of motor-skill learning cognitive, visuo-spatial and dynamic processes play an important role. Which of these should be addressed first when children need to learn a new complex movement sequence? This study compares three learning methods in a within-subject design by having 18 good and 18 poor 8-year-old writers master unfamiliar, letter-like patterns by (1) tracing a trajectory on a screen, (2) tracking a moving target (pursuit), and (3) performing the pattern using written explicit instructions. Following each 10-trial learning phase, the children completed a short test phase.

View Article and Find Full Text PDF

Background: In recent years the Netherlands has witnessed a steep increase in the number of bodies donated for medical research and training. To explore this upward trend and motives for donation, a survey was conducted among registered body donors in the database of the Department of Anatomy at the University Medical Center of Groningen (UMCG).

Methods: In November 2008, postal questionnaires were sent to 996 people enrolled at the UMCG body donor database.

View Article and Find Full Text PDF

A computational neural model of goal-directed utterance selection.

Neural Netw

June 2010

Centre for Language and Speech Technology, Radboud University of Nijmegen, Postbus 9103, 6500 HD Nijmegen, The Netherlands.

It is generally agreed that much of human communication is motivated by extra-linguistic goals: we often make utterances in order to get others to do something, or to make them support our cause, or adopt our point of view, etc. However, thus far a computational foundation for this view on language use has been lacking. In this paper we propose such a foundation using Markov Decision Processes.

View Article and Find Full Text PDF

Hepatitis B virus (HBV) replication starts with binding of reverse transcriptase (RT) to the apical stem-loop region of epsilon, a conserved element of the RNA pregenome. For duck HBV, an in vitro replication system has provided molecular details of this interaction. Further insights can be obtained from the structure and dynamics of the duck and human apical stem-loops.

View Article and Find Full Text PDF

The present study examined to what extent the number of friends and their social and personal characteristics were related to peer victimization in adolescence. Participants were 2,180 adolescents (1,143 girls), aged 11-18 (M = 14.2), who were classified as victims, bully-victims, or non-involved (i.

View Article and Find Full Text PDF

Biochemistry and molecular biology of anammox bacteria.

Crit Rev Biochem Mol Biol

June 2009

Department of Microbiology, IWWR, Faculty of Science, Radboud University of Nijmegen, Toernooiveld 1, Nijmegen, The Netherlands.

Anaerobic ammonium-oxidizing (anammox) bacteria are one of the latest additions to the biogeochemical nitrogen cycle. These bacteria derive their energy for growth from the conversion of ammonium and nitrite into dinitrogen gas in the complete absence of oxygen. These slowly growing microorganisms belong to the order Brocadiales and are affiliated to the Planctomycetes.

View Article and Find Full Text PDF

This paper reports on the ways in which new entities are introduced into discourse. First, we present the evidence in support of a model of indefinite reference processing based on three principles: the listener's ability to make predictive inferences in order to decrease the unexpectedness of upcoming words, the availability to the speaker of grammatical constructions that customize predictive inferences, and the use of "expectancy monitors" to signal and facilitate the introduction of highly unpredictable entities. We provide evidence that one of these expectancy monitors in Dutch is the post-verbal variant of existential er (the equivalent of the unstressed existential "there" in English).

View Article and Find Full Text PDF

Objective: Prepregnant low plasma volume (LPV) is associated with subsequent gestational hypertensive disease. It is unknown to what extent an LPV affects the venous reserve capacity (VRC). We tested the hypothesis that LPV reduces the VRC, as indicated by presyncope or altered cardiovascular changes in response to head-up tilt.

View Article and Find Full Text PDF

Conceptual knowledge for understanding other's actions is organized primarily around action goals.

Exp Brain Res

July 2008

Nijmegen Institute of Cognition and Information, Radboud University of Nijmegen, P. O. Box 9104, 6500 HE Nijmegen, The Netherlands.

Semantic knowledge about objects entails both knowing how to grasp an object (grip-related knowledge) and what to do with an object (goal-related knowledge). Considerable evidence suggests a hierarchical organization in which specific hand-grips in action execution are most often selected to accomplish a remote action goal. The present study aimed to investigate whether a comparable hierarchical organization of semantic knowledge applies to the recognition of other's object-directed actions as well.

View Article and Find Full Text PDF

This paper gives an overview of the ideas on cerebral localization as they were formulated in the Netherlands in the nineteenth century. In general, it appears that, given the discussions in France, Germany, and Britain, surprisingly little was written and hardly any serious research was performed. Special attention is given to the dissertation on the localization of sensory-motor functions by Aletta Jacobs (1854-1929), known for her social and political activities to improve the position of women.

View Article and Find Full Text PDF

Structure and dynamics of human apolipoprotein CIII.

J Biol Chem

June 2008

Department of Physical Chemistry-Biophysical Chemistry, Radboud University of Nijmegen, Toernooiveld 1, 6525 ED, Nijmegen, The Netherlands.

Human apolipoprotein CIII (apoCIII) is a surface component of chylomicrons, very low density lipoproteins, and high density lipoproteins. ApoCIII inhibits lipoprotein lipase as well as binding of lipoproteins to cell surface heparan sulfate proteoglycans and receptors. High levels of apoCIII are often correlated with elevated levels of blood lipids (hypertriglyceridemia).

View Article and Find Full Text PDF

Cocaine (COC) inhibits the re-uptake of dopamine. However, the dopamine response to COC also depends on dopamine inside storage vesicles. The aim of this study was to investigate whether rats that differentially respond to COC differ in their dopaminergic storage capacity of the nucleus accumbens.

View Article and Find Full Text PDF

Electron scattering on microscopic corrugations in graphene.

Philos Trans A Math Phys Eng Sci

January 2008

Institute for Molecules and Materials, Radboud University of Nijmegen, Toernooiveld 1, Nijmegen, The Netherlands.

We discuss various scattering mechanisms for Dirac fermions in single-layer graphene. It is shown that scattering on a short-range potential (e.g.

View Article and Find Full Text PDF

Visualisation and interpretation of Support Vector Regression models.

Anal Chim Acta

July 2007

Institute for Molecules and Materials, Analytical Chemistry, Radboud University of Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands.

This paper introduces a technique to visualise the information content of the kernel matrix and a way to interpret the ingredients of the Support Vector Regression (SVR) model. Recently, the use of Support Vector Machines (SVM) for solving classification (SVC) and regression (SVR) problems has increased substantially in the field of chemistry and chemometrics. This is mainly due to its high generalisation performance and its ability to model non-linear relationships in a unique and global manner.

View Article and Find Full Text PDF