The End of Reurbanisation? Phases of Concentration and Deconcentration in Migratory Movements in North Rhine-Westphalia

For some time now, there has been a lively debate about reurbanisation in Germany with regard to trends in spatial development. At the same time, the consequences of spatially imbalanced development can be observed in many regions. In large metropolitan areas in particular, the renewed appeal of cities has made living space scarce and expensive. There is extensive investment in residential construction and infrastructure, yet the first signs of a further shift in the trend are starting to emerge. It is against this background that this paper investigates migratory movements in the state of North Rhine-Westphalia, covering a period of more than four decades. The resulting change in the distance between place of residence and the nearest major centre is calculated for each case of migration in the time period under investigation. By aggregating the individual values, an indicator is generated that can be used to identify different phases of spatial concentration and deconcentration. The results remind us that for a long time the predominant forces in migratory movements were centrifugal. This makes the transition to the spatial concentration phase that took place in the past decade, and that can be precisely traced from the values obtained, all the more striking. In the final years of the period under investigation, the results are significantly influenced by the handling of the publicly-directed migration of refugees and asylum-seekers within the state. If municipalities with admission facilities for these groups that exhibit anomalous migration data are excluded from the analysis, deconcentration processes appear in fact to be gaining the upper hand again in North Rhine-Westphalia. Renewed momentum in residential suburbanisation in the areas surrounding the major centres is behind this current development. Deceleration of the migratory losses from more peripheral municipalities can also be observed, however

Detecting directional coupling in the human epileptic brain: Limitations and potential pitfalls

We study directional relationships—in the driver-responder sense—in networks of coupled nonlinear oscillators using a phase modeling approach. Specifically, we focus on the identification of drivers in clusters with varying levels of synchrony, mimicking dynamical interactions between the seizure generating region (epileptic focus) and other brain structures. We demonstrate numerically that such an identification is not always possible in a reliable manner. Using the same analysis techniques as in model systems, we study multichannel electroencephalographic recordings from two patients suffering from focal epilepsy. Our findings demonstrate that—depending on the degree of intracluster synchrony—certain subsystems can spuriously appear to be driving others, which should be taken into account when analyzing field data with unknown underlying dynamics

Internetwork and intranetwork communications during bursting dynamics: Applications to seizure prediction

We use a simple dynamical model of two interacting networks of integrate-and-fire neurons to explain a seemingly paradoxical result observed in epileptic patients indicating that the level of phase synchrony declines below normal levels during the state preceding seizures (preictal state). We model the transition from the seizure free interval (interictal state) to the seizure (ictal state) as a slow increase in the mean depolarization of neurons in a network corresponding to the epileptic focus. We show that the transition from the interictal to preictal and then to the ictal state may be divided into separate dynamical regimes: the formation of slow oscillatory activity due to resonance between the two interacting networks observed during the interictal period, structureless activity during the preictal period when the two networks have different properties, and bursting dynamics driven by the network corresponding to the epileptic focus. Based on this result, we hypothesize that the beginning of the preictal period marks the beginning of the transition of the epileptic network from normal activity toward seizing

Persistent Miscalibration for Low and High Achievers Despite Practice Test Feedback in an Introductory Biology Course

Students\u27 ability to accurately judge their knowledge is crucial for effective learning. However, students\u27 perception of their current knowledge is often misaligned with their actual performance. The relationship between learners\u27 perception of their performance and their actual performance on a task is defined as calibration. Previous studies have shown significant student miscalibration in an introductory biology course: students\u27 predicted exam scores were, on average, significantly higher than their actual scores. The goal of this study was to determine whether completion of a practice test before exams would result in better performance and calibration. The hypothesis was that students who completed a practice test would perform better and be better predictors of their performance on exams than students who did not engage in practice testing. As predicted, students who voluntarily completed a practice test, on average, performed better and were more calibrated than students who did not. Importantly, however, many of the lowest-performing students continued to significantly overestimate their knowledge, predicting higher scores on the exam than they actually earned, despite feedback from practice tests. In contrast, practice testing was associated with underconfidence in high-performing students. These findings indicate that practice tests may enhance calibration for many students. However, additional interventions may be required for the lowest-performing students to become better predictors of their performance

Defizitäre schlafassoziierte Gedächtniskonsolidierung emotionaler Inhalte bei Kindern mit einer Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung (ADHS)

Untersuchung zur schlafassoziitern Konsolidierung bei Kindern im Hinblick auf Hypofrontalität bei Kindern mit einer ADHS, Differenzierung zwischen emotionalen und neutralen Gedächtnisinhalten und Differenzierung schlafassoziierter Prozessen zur Enkodierungsprozessen

Sinkende Einzelhandelsmieten in Innenstädten: Ausdruck der Krise oder Chance für Wiederbelebung?

Die typische Fußgängerzone war lange Zeit durch Kauf- und Warenhäuser, später dann durch innerstädtische Einkaufszentren geprägt. Um solche Fixpunkte gruppierten sich viele andere Einzelhandelsbetriebe. Nutzungen wie Wohnen wurden dagegen in andere Bereiche der Stadt verlagert. Solche Strukturen funktionieren heute immer weniger. Der Beitrag zeigt, dass es konkrete Anzeichen für eine nachlassende Attraktivität der Innenstädte gibt und dass Marktanpassungsprozesse, sinkende Einzelhandelsmieten und zunehmende Leerstände nicht nur in Großstädten, sondern auch in Mittel- und Kleinstädten zu beobachten sind. Es stellt sich die Frage, ob sinkende Mieten nicht nur als Ausdruck der Krise, sondern auch als Chance für die Wiederbelebung der Innenstädte angesehen werden können und ob neue Nutzungen zu einer Nutzungsmischung führen

The neutron fission cross section of 92U235 and 92U238 in the energy range 0.3-12.5 MeV

The experimental and theoretical work was aimed at determining the neutron fission cross sections of U-235 and U-2S8 in the energy range 0.3 - 12.5 MeV with good resolution and reasonable statistics. The main instrument used was the 100 MeV electron linear accelerator of the laboratory, providing a pulsed neutron source in connection with a bremsstrahlung target. To carry out the research, it was primarily necessary, to understand the fission process in detail and the associated models. To describe it and the cross sections required the use of the liquid drop model, shell corrections, the optical and the statistical model. To see the present work in perspective, a review of past and present work in this field was necessary. The main instrument, apart from the accelerator, with which the experiments were carried out, was a high resolution gas scintillator, used as a time-of-flight spectrometer. This scintillator was developed by the author with Xenon as the gas in question, and by using a Cf-252 natural fission source for testing during the development. The monitor detectors, chosen for the experiments, were standard neutron detectors. During a series of accelerator tests the optimum electronic data collection system was developed by the author. This was assisted by a bi-dimension data storage programme for a FDP-7 on line computer, earlier written by J. D. Kellie. Apart from the time to energy conversion, which was done by a computer code by J. D. Kellie, the analysis of the data was entirely original, especially the background subtraction. Although the mathematical mechanism had been developed by J. D. Kellie, the criteria for this sub-traction were due to the author. This is also true for all normalizations and corrections. Interpretation of the general shape of the cross sections as well as interpretation of any apparent structure has been carried out solely by the author. The computer programmes for the theoretical calculations, including fission, neutron-capture-x-ray-emission, total scattering transmission coefficients and the final cross section calculations, have been written by the author himself, and only a code by J. D. Kellie for the calculation of the incoming wave transmission coefficients was adopted

Independent Delta/Theta Rhythms in the Human Hippocampus and Entorhinal Cortex

Theta oscillations in the medial temporal lobe (MTL) of mammals are involved in various functions such as spatial navigation, sensorimotor integration, and cognitive processing. While the theta rhythm was originally assumed to originate in the medial septum, more recent studies suggest autonomous theta generation in the MTL. Although coherence between entorhinal and hippocampal theta activity has been found to influence memory formation, it remains unclear whether these two structures can generate theta independently. In this study we analyzed intracranial electroencephalographic (EEG) recordings from 22 patients with unilateral hippocampal sclerosis undergoing presurgical evaluation prior to resection of the epileptic focus. Using a wavelet-based, frequency-band-specific measure of phase synchronization, we quantified synchrony between 10 different recording sites along the longitudinal axis of the hippocampal formation in the non-epileptic brain hemisphere. We compared EEG synchrony between adjacent recording sites (i) within the entorhinal cortex, (ii) within the hippocampus, and (iii) between the hippocampus and entorhinal cortex. We observed a significant interregional gap in synchrony for the delta and theta band, indicating the existence of independent delta/theta rhythms in different subregions of the human MTL. The interaction of these rhythms could represent the temporal basis for the information processing required for mnemonic encoding and retrieval

Opportunities for Self-Evaluation Increase Student Calibration in an Introductory Biology Course

Accurate self-evaluation is critical for learning. Calibration describes the relationship between learners’ perception of their performance and their actual performance on a task. Here, we describe two studies aimed at assessing and improving student calibration in a first-semester introductory biology course at a 4-year public institution. Study 1 investigated students’ (n = 310) calibration (the difference between estimated and actual exam performance) across one semester. Students were significantly miscalibrated for the first exam: their predicted scores were, on average, significantly higher than their actual scores. The lowest-performing students had the most inaccurate estimates. Calibration improved with each exam. By the final exam, students underestimated their scores. We initiated a second study in the following semester to examine whether explicitly teaching students about self-evaluation strategies would improve their calibration and performance. Instruction in the experimental section (n = 290) focused on students’ tendency to overestimate their abilities and provided retrieval-practice opportunities. Students in the experimental section showed better calibration and performance on the first exam compared with students in a control section taught by a different instructor during the same semester (n = 251). These findings suggest that simple instructional strategies can increase students’ metacognitive awareness and improve their performance